Pourquoi l’alcool augmente le risque de cancer, et ce, dès le premier verre

Source: The Conversation – France in French (3) – By Pranoti Mandrekar, Professor of Medicine, UMass Chan Medical School

En matière de cancer, il n’existe pas de consommation d’alcool sans risque. Krit of Studio OMG/Moment/Getty Images

Notre corps paye un tribut à l’alcool, qu’il soit consommé régulièrement ou occasionnellement. Cette substance a des effets nocifs sur la santé, affectant de nombreux organes, du cerveau au système gastro-intestinal, en passant par les poumons, les muscles (y compris le cœur) et le système immunitaire. On sait aujourd’hui que l’alcool provoque notamment des cancers.


Aux États-Unis, l’alcool est responsable d’environ 100 000 cas de cancer et de 20 000 décès par cancer chaque année, ce qui en fait la troisième cause évitable de cancer. À titre de comparaison, les accidents de la route liés à l’alcool causent environ 13 500 décès par an aux États-Unis.

(En France, en 2018, 28 000 nouveaux cas de cancers étaient attribuables à l’alcool, soit 8 % des cas incidents de cancer, avec une répartition de 11 % chez les hommes et 4,5 % chez les femmes. Les accidents de la route en lien avec une consommation d’alcool et/ou de stupéfiants ont causé près de 1 250 décès en 2024, l’alcool étant impliqué dans les trois quarts des cas, ndlr).

Les scientifiques ont soupçonné dès les années 1980 que l’alcool pouvait provoquer le cancer. Des études épidémiologiques ont, depuis, montré que la consommation d’alcool augmente le risque de cancers de la cavité buccale, de la gorge, du larynx, de l’œsophage, du foie, du côlon et du rectum, ainsi que du sein. D’autres travaux ont révélé une association entre consommation chronique ou alcoolisation massive ponctuelle et cancer du pancréas.

En 2000, les responsables du National Toxicology Program des États-Unis ont conclu que la consommation de boissons alcoolisées devait être considérée comme cancérogène avéré pour l’être humain. En 2012, le Centre international de recherche sur le cancer (CIRC), l’agence spécialisée dans le cancer de l’Organisation mondiale de la santé, a classé l’alcool parmi les cancérogènes du groupe 1. L’appartenance d’une substance à cette catégorie, la plus élevée dans la classification du CIRC, indique qu’il existe des preuves scientifiques suffisantes pour conclure qu’elle cause des cancers chez l’être humain. Les Centers for Disease Control and Prevention et les National Institutes of Health s’accordent eux aussi à dire que les preuves sont concluantes : l’alcool est bien à l’origine de différents types de cancers.

Par ailleurs, aux États-Unis (comme en France, ndlr), les autorités sanitaires soulignent que même de faibles quantités d’alcool – moins d’un verre par jour – augmentent le risque de cancer.

Malgré tout, nombre de citoyens ne savent pas que l’alcool cause des cancers. En 2019, moins de 50 % des adultes aux États-Unis avaient conscience des liens entre consommation d’alcool et risque cancérogène.

En France, le lien entre alcool et cancer est également sous-estimé par une partie de la population. L’enquête Baromètre cancer de 2021, menée par l’Institut national du cancer, a révélé que 38,6 % des personnes interrogées pensent que « ce sont surtout les alcools forts qui augmentent le risque de cancer », tandis que 23,5 % estiment que « globalement, boire un peu de vin diminue le risque de cancer plutôt que de ne pas en boire du tout », alors même que le « French paradox » _est désormais battu en brèche, ndlr_.

En outre, l’édition 2023 de la National Survey on Drug Use and Health a relevé que plus de 224 millions d’Américains, âgés de 12 ans et plus, avaient consommé de l’alcool à un moment de leur vie – soit plus de 79 % des personnes de ce groupe d’âge. La consommation d’alcool augmentait déjà avant la pandémie de Covid-19, ce qui constitue un sujet de santé publique préoccupant.

En France, selon les données recueillies par Santé publique France, la consommation quotidienne d’alcool diminue régulièrement depuis trente ans. On constate toutefois que, si les « alcoolisations ponctuelles importantes » ont tendance à diminuer chez les jeunes hommes, elles augmentent de manière sensible chez les femmes de plus de 35 ans. Dans les deux cas, les disparités régionales sont marquées, ndlr.

En tant que chercheuse, j’étudie les effets biologiques de la consommation modérée et de longue durée d’alcool. Mon équipe travaille à élucider les mécanismes par lesquels l’alcool accroît le risque de cancer, en particulier via les atteintes portées aux cellules immunitaires et au foie.

L’administrateur de la santé publique des États-Unis a appelé à faire figurer le risque de cancer sur les étiquettes d’avertissement des bouteilles d’alcool.

Comment l’alcool provoque-t-il le cancer ?

Le cancer survient lorsque des cellules se mettent à croître de manière incontrôlée dans l’organisme. L’alcool peut favoriser la formation de tumeurs en endommageant l’ADN, provoquant des mutations qui perturbent la division et la croissance cellulaires.

Les chercheurs ont identifié plusieurs mécanismes pouvant expliquer comment la consommation d’alcool mène au développement de cancers. Un rapport publié en 2025 par l’administrateur de la santé publique des États-Unis (surgeon general of the United States) a répertorié quatre voies principales par lesquelles l’alcool peut causer le cancer :

  • le métabolisme de l’alcool,
  • le stress oxydatif et l’inflammation,
  • les altérations des niveaux hormonaux,
  • les interactions avec d’autres cancérogènes (comme la fumée de tabac).

L’expression « métabolisme de l’alcool » – la première voie par laquelle cette substance peut provoquer des cancers – désigne les processus grâce auxquels l’organisme dégrade et élimine l’alcool. Une fois ingéré, ce dernier subit, sous l’effet de diverses enzymes, des transformations chimiques qui vont permettre son élimination (on dit qu’il est « métabolisé »). Le premier sous-produit de ces réactions est l’acétaldéhyde, une substance elle-même classée comme cancérogène. Les scientifiques ont montré que certaines mutations génétiques peuvent amener l’organisme de certains individus à décomposer l’alcool plus rapidement, entraînant des niveaux accrus d’acétaldéhyde.

La seconde voie par laquelle l’alcool augmente le risque de survenue de cancer implique d’autres molécules nocives, appelées « radicaux libres ». L’alcool peut déclencher la libération de ces molécules chimiquement très réactives, qui endommagent l’ADN, les protéines et les lipides des cellules par un processus dit de « stress oxydatif ». Mon laboratoire a montré que les radicaux libres issus de la consommation d’alcool peuvent influer directement sur la manière dont les cellules synthétisent et dégradent les protéines, entraînant la production de protéines anormales qui entretiennent une inflammation propice à la formation de tumeurs.

Verre tulipe renversé contenant un liquide ambré, sur fond sombre
Réduire sa consommation d’alcool diminue le risque de cancer.
Mordyashov_Aleks/500px/Getty Images

Le risque de cancer peut également être accru par l’alcool d’une troisième façon, en raison de la capacité de cette substance à modifier les niveaux hormonaux. On sait qu’une consommation modérée d’alcool peut non seulement augmenter les niveaux d’œstrogènes, mais aussi favoriser la poursuite de la consommation. Or, des travaux ont montré que le risque de cancer du sein peut être augmenté par le niveau d’œstrogène. L’alcool amplifie également le risque de cancer du sein en réduisant les niveaux de vitamine A, laquelle régule les œstrogènes.

Enfin, l’alcool augmente le risque de cancer en interagissant avec d’autres substances cancérogènes. On sait par exemple que les personnes qui boivent et fument présentent un risque accru de développer un cancer de la bouche, du pharynx et du larynx. C’est parce que l’alcool facilite l’absorption, par l’organisme, des cancérogènes contenus dans les cigarettes et les cigarettes électroniques.

En l’état actuel des connaissances, le risque de cancer associé à l’utilisation à long terme des vapoteuses semble bien moindre que celui des cigarettes de tabac, mais il n’en est pas pour autant nul (comparé au fait de ne pas en utiliser) ; en cause, la présence de certains constituants potentiellement mutagènes ou cancérogènes dans les aérosols générés par les cigarettes électroniques, qui pourrait influer sur le risque de certains cancers, notamment en cas d’utilisation prolongée. Des données complémentaires doivent cependant encore être recueillies pour évaluer ledit risque, ndlr.

En outre, le tabagisme, à lui seul, peut également provoquer une inflammation, induisant des radicaux libres qui endommagent l’ADN.

Quelle dose d’alcool est sans danger ?

Si vous buvez de l’alcool, vous vous êtes peut-être déjà demandé s’il existe une dose minimale permettant une consommation sans risque. La réponse des cliniciens et des scientifiques risque de ne pas vous plaire : la consommation d’alcool n’est jamais sans risque.

Le risque de cancer augmente dès le premier verre et s’accroît avec la quantité consommée, quel que soit le type de boisson alcoolisée ingérée.

Aux États-Unis, les Centers for Disease Control and Prevention, le National Institute on Alcohol Abuse and Alcoholism et l’administrateur de la santé publique des États-Unis préconisent de ne pas dépasser un verre par jour pour les femmes et deux verres pour les hommes

En France, les repères de consommation d’alcool « à moindre risque » n’établissent pas de distinction entre les sexes. Pour communiquer sur le sujet, les autorités ont retenu la formule : « [Pour votre santé, l’alcool c’est maximum deux verres par jour, et pas tous les jours(https://www.drogues.gouv.fr/campagne-alcool-nouveaux-reperes-de-consommation-moindre-risque) »], ndlr.

La consommation d’alcool est donc une cause de cancer hautement évitable.

Il n’existe toutefois pas, à ce jour, de méthode pour déterminer le risque individuel de développer un cancer lié à l’alcool. Le profil génétique propre à chacun, le mode de vie, l’alimentation et d’autres facteurs peuvent influer sur la propension de l’alcool à mener à la formation de tumeurs. Une chose est sûre : reconsidérer ses habitudes de consommation peut contribuer à protéger sa santé et à réduire son risque de cancer.


Pour aller plus loin

The Conversation

Pranoti Mandrekar ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

ref. Pourquoi l’alcool augmente le risque de cancer, et ce, dès le premier verre – https://theconversation.com/pourquoi-lalcool-augmente-le-risque-de-cancer-et-ce-des-le-premier-verre-263022

Syndrome de Korsakoff : une démence évitable, due à l’alcool, mais que la France ignore

Source: The Conversation – France in French (3) – By Mickael Naassila, Professeur de physiologie, Directeur du Groupe de Recherche sur l’Alcool & les Pharmacodépendances GRAP – INSERM UMR 1247, Université de Picardie Jules Verne (UPJV)

En France, des milliers de personnes vivent, littéralement, dans l’oubli ; parfois, au cœur même de nos structures sanitaires ou médico-sociales. Ces patients présentent un syndrome de Korsakoff, une pathologie grave, méconnue, souvent confondue avec la « démence alcoolique » ou autres troubles cognitifs. Mais le plus inquiétant est peut-être que l’immense majorité de ces cas pourraient être évités, grâce à un simple apport en vitamine. À condition qu’ils soient correctement diagnostiqués.


Lorsque l’on pense « démence précoce », autrement dit problèmes de mémoire avant 65 ans, les premiers mots qui viennent à l’esprit sont généralement « maladie d’Alzheimer ». Pourtant, dans les pays occidentaux, la première cause de démence avant 65 ans est… l’alcool. Ce fait, peu connu du grand public, est aussi ignoré par de nombreux professionnels de santé.

Parmi les troubles cognitifs causés par l’alcool figure le syndrome de Korsakoff. Cette affection sévère, chronique et irréversible résulte de la combinaison de deux mécanismes : la toxicité directe de l’alcool pour les neurones et, surtout, la carence en thiamine (vitamine B1).

Alors que les carences en thiamine sont faciles à diagnostiquer et à prévenir, elles restent pourtant massivement négligées, ce qui condamne des milliers de patients.

Alcool et démence

Les résultats de divers travaux de recherche indiquent que consommation excessive d’alcool et risque de démence sont étroitement liés.

En France, une étude menée sur une vaste cohorte nationale comportant plus de 57 000 cas de démence précoce a révélé qu’environ 60 % des cas survenus avant 65 ans étaient liés à l’alcool.

Les résultats d’une autre étude, menée en Finlande, indiquent quant à eux que le trouble de l’usage de l’alcool multiplie par environ 5,7 le risque de démence précoce chez les hommes et par 6,1 chez les femmes. Une autre revue de littérature scientifique récente indique également que la consommation excessive d’alcool est responsable de 8 % des nouveaux cas de démence chez les hommes de 45 à 64 ans.

Enfin, selon l’organisme caritatif britannique Alzheimer’s Society, environ une personne sur huit atteinte de démence précoce souffre de troubles cognitifs liés à l’alcool, fréquemment diagnostiqués entre 40 et 50 ans.

Les déficits cognitifs liés à l’alcool s’inscrivent dans un continuum allant de ceux liés au « binge drinking », à ceux liés au trouble de l’usage d’alcool, jusqu’au terrible syndrome de Korsakoff, qui détruit irréversiblement la mémoire des patients.

Pertes de mémoire et confusion

Les patients atteints par le syndrome de Korsakoff souffrent de graves troubles de la mémoire.

Leurs souvenirs d’avant la maladie disparaissent (on parle d’« amnésie rétrograde »), et ils sont également incapables d’en fabriquer de nouveaux (« amnésie antérograde »). Souvent, ces trous sont meublés par de faux souvenirs, des fabulations qui permettent aux patients de donner le change, ainsi que par de fausses reconnaissances.

Ce syndrome se traduit également par une perte de repères temporels et spatiaux : les malades ont des difficultés à se situer dans le temps et dans l’espace. Ils deviennent, par exemple, incapables de se souvenir du chemin qu’ils empruntaient pour aller faire leurs courses hebdomadaires.

Ils souffrent aussi de problèmes d’équilibre et de difficultés à marcher, en raison de troubles de la coordination des mouvements (« ataxie ») et de problèmes oculaires se traduisant par des mouvements incontrôlés des yeux.

Les personnes atteintes du syndrome de Korsakoff sont également atteintes d’« anosognosie » : elles sont incapables de prendre conscience d’un ou plusieurs de leurs propres déficits. Enfin, elles peuvent présenter des troubles du comportement.

Le syndrome de Korsakoff se développe généralement à la suite d’une autre affection, l’encéphalopathie de Gayet-Wernicke. Si cette phase aiguë est traitée rapidement, son évolution peut être favorable. Malheureusement, jusqu’à 80 % des personnes atteintes par une encéphalopathie de Gayet-Wernicke ne sont pas diagnostiquées et ne reçoivent donc pas le traitement adapté, qui consiste en une simple supplémentation vitaminique.

Résultat : le syndrome de Korsakoff, la forme chronique et irréversible de l’encéphalopathie de Gayet-Wernicke, se met en place.

Un problème de vitamine B1

Les symptômes de l’encéphalopathie de Gayet-Wernicke et du syndrome de Korsakoff sont dus à la présence de lésions dans diverses zones du cerveau des malades. Ces dommages sont la conséquence d’un déficit en vitamine B1.

Aussi appelée thiamine, cette dernière joue un rôle important dans la maintenance du système nerveux. Il s’agit d’une vitamine dite « essentielle », ce qui signifie que le corps humain n’est pas capable de la produire. Elle doit donc être apportée par l’alimentation : la prise de 1 mg à 2 mg par jour suffit à couvrir les besoins d’une personne en bonne santé.

Naturellement présente dans certains produits, la thiamine est aussi ajoutée à d’autres. Elle peut, par ailleurs, être consommée sous forme de compléments alimentaires. Parmi les sources de thiamine figurent notamment le riz brun, les céréales complètes, le porc, la volaille, le soja, les noix, les pois, les haricots secs ainsi que les produits céréaliers enrichis ou fortifiés, tels que le pain, les céréales et les préparations pour nourrissons.

S’il arrive que l’encéphalopathie de Gayet-Wernicke résulte de problèmes nutritionnels dus à une alimentation trop pauvre en thiamine (dans diverses régions du monde, la carence en vitamine B1 est à l’origine du béribéri), dans près de 90 % des cas cette pathologie concerne des patients présentant un trouble de l’usage de l’alcool.
Souvent, en effet, ces derniers mangent trop peu, les boissons alcoolisées leur fournissant une partie de leurs apports énergétiques.

Par ailleurs, la consommation d’alcool diminue l’absorption gastro-intestinale et le stockage hépatique de la thiamine, tout en augmentant son utilisation par les cellules. Enfin, diarrhées et vomissements peuvent aussi aggraver les problèmes d’absorption.

Cela signifie que le syndrome de Korsakoff pourrait être largement évité par l’administration précoce de thiamine, en particulier chez toute personne avec un trouble de l’usage de l’alcool, même sans symptômes neurologiques nets. Pourtant, cette vitamine bon marché, sans risque majeur, n’est que très rarement prescrite dans les services d’urgence, en addictologie ou en médecine générale.

En cause, notamment, la méconnaissance du fait que seule une minorité de patients présente un tableau clinique classique complet. Ce constat a conduit plusieurs associations de patients et de familles à alerter sur la carence de repérage, de diagnostic et de prise en charge de ces pathologies

Le sous-diagnostic, à l’origine d’un scandale sanitaire silencieux

L’encéphalopathie de Gayet-Wernicke est souvent mal diagnostiquée, car la triade de symptômes « confusion, troubles oculomoteurs, ataxie » considérée comme son tableau clinique dit classique n’est complète que chez 16 % des patients.

Il faut donc l’abandonner et utiliser à la place les critères de Caine, établis par la neuropsychologue Diana Caine et ses collaborateurs. Validés par des études cliniques et neuropathologiques, recommandés par les sociétés savantes, ils sont aujourd’hui considérés comme les plus fiables : ils permettent de multiplier par quatre la sensibilité du diagnostic d’encéphalopathie de Gayet-Wernicke, lequel repose sur la présence d’au moins 2 des 4 critères.

Les critères cliniques de Caine (1997) pour diagnostiquer l’encéphalopathie de Gayet-Wernicke

  • Déficits nutritionnels documentés : IMC très bas, perte de poids, dénutrition sévère, malabsorption, régime très restrictif, vomissements fréquents ;
  • Troubles oculomoteurs : nystagmus, ophtalmoparésie, paralysie du regard, diplopie ;
  • Syndrome cérébelleux : ataxie, démarche instable, dysmétrie, troubles de l’équilibre ;
  • État confusionnel ou troubles de la mémoire : désorientation, attention fluctuante, troubles mnésiques modérés à sévères.

Chez les patients avec trouble de l’usage de l’alcool, la présence d’un seul critère doit déjà alerter sur un risque élevé d’encéphalopathie de Gayet-Wernicke, justifiant une administration immédiate de thiamine, sans attendre les résultats d’imagerie ou de biologie.

En effet, les lésions cérébrales irréversibles surviennent rapidement et une fois le syndrome de Korsakoff installé, il n’existe aucun traitement curatif. Seules des approches de remédiation cognitive ou de soutien social peuvent alors limiter les dégâts.

Cette situation a conduit plusieurs associations de patients et de familles de patients à alerter sur la carence de repérage, de diagnostic et de prise en charge de ces pathologies, qui concerneraient de 60 000 à 100 000 personnes en France.

Des patients plutôt masculins

Chaque année, dans notre pays, de 600 à 900 personnes développeraient un syndrome de Korsakoff. À l’heure actuelle, on dispose à de peu de données concernant son épidémiologie. On sait cependant qu’il touche surtout des individus présentant un trouble de l’usage de l’alcool sévère et une carence prolongée en vitamine B1.

Le risque d’être atteint par ce syndrome augmente fortement lorsque la consommation est élevée (soit, par jour, 6 à 8 verres d’alcool, selon que l’on est respectivement une femme ou un homme) et qu’elle se maintient sur une durée prolongée (de plusieurs années, souvent supérieure à dix ans). Il est aussi aggravé par la malnutrition, les épisodes de sevrage répétés sans prise en charge, ou encore les maladies qui augmentent les besoins ou réduisent l’absorption.

Une étude récente menée en Finlande a rapporté une incidence (nombre de nouveaux cas) de 3,7 (pour les hommes) et de 1,2 (pour les femmes) pour 100 000 personnes-années. Ces travaux révèlent aussi que 56 à 84 % des patients qui survivent à une encéphalopathie de Wernicke non traitée développent un syndrome de Korsakoff.

Une étude observationnelle rétrospective, publiée en 2025 et menée sur 1 320 patients pris en charge à l’Assistance publique–Hôpitaux de Paris (AP–HP) entre 2017 et 2022, a révélé que la majorité des patients était de sexe masculin (72,9 %). Leur âge moyen était de 62,9 ans, et ils étaient principalement pris en charge dans les services de médecine interne (22,1 %).

Les principales pathologies associées au syndrome de Korsakoff étaient l’hypertension artérielle (fréquence de 34 %) et un épisode dépressif (fréquence de 23,7 %). Le suivi médian de trois ans de ces patients a montré un mauvais pronostic, se traduisant par des atteintes sévères de la cognition, un taux de récupération faible, et un taux de mortalité élevé (30,2 %).

Enfin, l’étude menée sur les patients de l’AP-HP a permis d’estimer les coûts hospitaliers annuels moyens pour les patients atteints du syndrome de Korsakoff : 15 346 euros par patient, ce qui représente un déficit annuel de 8 507 euros par cas et par hôpital. Les auteurs insistent sur le fait que la mise en place d’un parcours de soins spécifique est nécessaire pour améliorer la survie de ces personnes.

Une insupportable errance médicale

De nombreux patients atteints d’un syndrome de Korsakoff subissent une difficile errance médicale. Ils sont souvent considérés comme trop jeunes pour la gériatrie, trop désorientés pour les structures médico-sociales classiques, trop stabilisés pour la psychiatrie aiguë, et trop lourds pour les centres d’addictologie.

Le syndrome de Korsakoff concentre en effet plusieurs angles morts de notre système de santé : la stigmatisation des troubles de l’usage d’alcool, la marginalisation des personnes en précarité, ou encore le sous-investissement dans la prévention nutritionnelle. Ces patients, souvent jeunes, sont perçus comme responsables de leur état, ce qui freine l’accès aux soins. La lecture des nombreux témoignages existants est édifiante.

Contrairement à d’autres pays, comme les Pays-Bas ou la Belgique, la France ne dispose d’aucune filière de soins spécialisée. L’absence de réponse structurée aggrave la perte d’autonomie, alourdit le fardeau des familles et rend la réinsertion quasiment impossible. À Roubaix, toutefois, une maison d’accueil a été spécifiquement créée pour accueillir les femmes atteintes du syndrome.

Un plan national pour sortir du déni

Le syndrome de Korsakoff n’est pas le résultat d’un simple excès de boisson, mais bien d’un enchaînement évitable de négligences médicales (notamment l’insuffisance de repérage précoce du mésusage de l’alcool), nutritionnelles et sociales.

Il est possible de lutter contre ce fléau en mettant en place quatre types d’actions :

  1. La prescription systématique de thiamine par voie intraveineuse ou intramusculaire chez tout patient suspecté de trouble de l’usage de l’alcool, ou en état de sevrage.
  2. L’organisation de campagne de formation des professionnels de santé pour repérer les encéphalopathies de Wernicke précoces et éviter les erreurs diagnostiques.
  3. La création, à l’échelle régionale, de structures spécialisées destinées à accueillir les patients avec syndrome de Korsakoff pour leur proposer soins, réhabilitation cognitive et accompagnement social.;
  4. L’intégration du risque de démence liée à l’alcool dans les politiques publiques de prévention et dans les parcours de soins en addictologie.

Le syndrome de Korsakoff n’est pas une fatalité. C’est le produit d’un déni collectif face à une forme de démence évitable, souvent installée à l’âge de 40 ou 50 ans, dans l’indifférence. Si rien n’est fait, ces patients continueront à disparaître lentement, dans un silence médical et politique injustifiable.

Chez les patients à risque, gare au glucose !

  • Administrer du glucose à un patient à risque lors de sa prise en charge peut précipiter le déclenchement d’une encéphalopathie aiguë. En effet, donner du sucre à quelqu’un qui manque de vitamine B1 risque de « brûler » ses dernières réserves et d’abîmer son cerveau en quelques heures. Pour cette raison, il est recommandé d’administrer la thiamine avant ou en même temps que le glucose.

Pour en savoir plus

The Conversation

Mickael Naassila est Président de la Société Française d’Alcoologie (SFA) et de la Société Européenne de Recherche Biomédicale sur l’Alcoolisme (ESBRA); Vice-président de la Fédération Française d’Addictologie (FFA) et vice-président junior de la Société Internationale de recherche Biomédicale sur l”Alcoolisme (ISBRA). Il est membre de l’institut de Psychiatrie, co-responsable du GDR de Psychiatrie-Addictions et responsable du Réseau National de Recherche en Alcoologie REUNIRA et du projet AlcoolConsoScience. Il a reçu des financements de l’ANR, de l’IReSP/INCa Fonds de lutte contre les addictions.

ref. Syndrome de Korsakoff : une démence évitable, due à l’alcool, mais que la France ignore – https://theconversation.com/syndrome-de-korsakoff-une-demence-evitable-due-a-lalcool-mais-que-la-france-ignore-261239

Weight loss support before IVF could boost pregnancy chances – and reduce the need for treatment

Source: The Conversation – UK – By Nerys M. Astbury, Associate Professor, Health Behaviours, University of Oxford

Close-up of in vitro fertilisation in a petri dish Rohane Hamilton/Shutterstock

Around one in five women of childbearing age are living with [obesity], defined by the World Health Organization as having a body mass index (BMI) over 30 kg/m². Compared with women in the healthy BMI range (18.5–24.9 kg/m²), those living with obesity are three times more likely to experience fertility problems and nearly twice as likely to have a miscarriage. Many turn to in vitro fertilisation (IVF) in the hope of having a baby.

Women with obesity who are planning a pregnancy are already advised that losing weight can improve their chances of conceiving. Our research suggests that structured weight loss support may also improve outcomes for those seeking IVF.

Our study analysed data from 12 international trials involving 1,921 women living with obesity, all planning IVF. It compared those offered a weight loss programme before IVF with those receiving standard care, which typically does not include such support.

Women who took part in a weight loss programme had a 21% higher chance of becoming pregnant overall – whether naturally or through IVF. The biggest difference was in natural conceptions: the likelihood of getting pregnant without IVF rose by 47%, meaning some women avoided fertility treatment altogether.

However, despite these higher pregnancy rates and no increase in miscarriage risk, there was no clear evidence of an effect on live birth rates. This may be because many of the included studies didn’t track live birth outcomes – even though this is the result that matters most to patients.

IVF access paradox

In the UK, publicly funded IVF is restricted to women with a BMI under 30. Similar weight-based eligibility rules exist in many other countries. These policies disproportionately affect women from more deprived backgrounds and some ethnic groups, who are more likely to be living with obesity.

The paradox is clear: women with obesity are more likely to need IVF, but less likely to be eligible for it.

Some can afford private weight loss programmes to meet the BMI requirement. Others resort to unproven or unsafe methods to lose weight quickly, risking their health in order to access fertility care.

Our research findings suggest that offering structured weight loss programmes to women with obesity who are otherwise ineligible for IVF could help more women become pregnant – and in some cases avoid IVF altogether.

This approach could also make fertility treatment more equitable. Since the cost of weight loss support is relatively low compared with IVF, including it in the treatment pathway might offer better value for healthcare providers.

Weight loss options before IVF

The most effective non-surgical option for significant weight loss is a class of medications called GLP-1 receptor agonists – such as Wegovy or Mounjaro – which have been shown to lead to substantial weight reduction.

However, these drugs should not be used during pregnancy, while trying to conceive, or while breastfeeding, as there’s little safety data in humans – and animal studies suggest potential harm to foetal development. Anyone who becomes pregnant while taking GLP-1 drugs should stop immediately and consult a healthcare professional.

For women planning to conceive soon, there are other safe and effective options, including structured support groups and low-energy diet programmes. The problem is that such services are not offered as part of standard IVF care.

While some NHS weight management programmes exist, access is limited, waiting lists can be long, and most are aimed at people with obesity-related health conditions rather than those seeking fertility treatment. In many other countries, insurance coverage for weight loss support is similarly patchy, meaning these services must often be funded privately – a cost that can put them out of reach for those who could benefit most.

The message from this research is clear: targeted, supportive weight loss programmes before IVF don’t just improve pregnancy chances – they could also reduce the need for IVF, promote fairer access to fertility treatment, and save healthcare resources. The challenge now is making sure they’re available to everyone who needs them, not just those who can afford to pay.

The Conversation

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

ref. Weight loss support before IVF could boost pregnancy chances – and reduce the need for treatment – https://theconversation.com/weight-loss-support-before-ivf-could-boost-pregnancy-chances-and-reduce-the-need-for-treatment-260544

Whales and dolphins regularly hang out with each other – new study

Source: The Conversation – Global Perspectives – By Olaf Meynecke, Research Fellow in Marine Science and Manager Whales & Climate Program, Griffith University

drewsulockcreations/Getty

As the annual humpback whale migration is underway with thousands of whales passing by the Australian coast, there are reports of dolphins joining the mass movement.

But this isn’t a one off. In fact, our new study, published today in Discover Animals, shows interspecies interactions between dolphins and whales are widespread and frequent around the world.

An astonishing interaction

There have been several reports of whale and dolphin interaction in the past.

One that astonished the public back in 2004 featured a humpback whale in Hawaii repeatedly lifting a bottlenose dolphin on its head.

Researchers suggested such close contact between whales and dolphins is likely very rare – and maybe related to care giving.

But other forms of interactions resembling joint feeding, play and harassment are now being frequently documented thanks to drone technology. Many are also featured on social media.

A ‘whale’s-eye view’ of the world

For our new study, we undertook an analysis of 199 independent whale-dolphin interaction events involving 19 different species. These interactions spanned two decades and occurred across 17 countries.

We drew from social media platforms – such as Facebook, YouTube and Instagram – and footage contributed by citizens to get a variety of observations.

Each entry was carefully reviewed to identify the species involved, validate the interaction and categorise behaviours. Two additional cases came from camera tags attached to humpback whales. These offered an underwater “whale’s-eye view” of their encounters with dolphins.

We categorised behaviours such as rolling, tail slaps, bow riding, and rubbing, and classified dolphin positions relative to whale body parts such as head, flank and tail fluke.

Having fun or fighting?

The study contradicted earlier assumptions that interspecies interactions between dolphins and whales are very rare.

The most common interaction was dolphins swimming near the whale’s head (akin to bow riding). This accounted for 80% of observed dolphin positions. Humpback whales were the most involved whale species, while bottlenose dolphins led the dolphin side.

Based on videos we analysed, dolphins initiated most interactions through bow riding, swimming in formation, or even touching whales.

In more than one-quarter of the events, the whales responded in seemingly similar ways. For example, humpback whales often rolled, exposed their bellies, or gently turned toward dolphins.

Tail slaps and other signs of distress or aggression were rare (roughly 5% of cases).

As a result of this, we classified more than one-third of all interactions between humpback whales and dolphins as positive or possible social play.

The two camera-tag videos revealed previously undocumented interaction. Dolphins were observed following humpback whales not only at the surface but down to the ocean floor. They maintained eye contact or even touched the whales’ head – suggesting intentional, possibly social, engagement.

Reflecting advanced emotional capabilities

The findings reshape our understanding of how social marine mammals interact across species. They suggest interspecies interaction among marine mammals may be far more prevalent and complex than previously believed.

Dolphins may seek out whales as companions for stimulation, play or even courtship-like behaviour. Meanwhile, certain whale species, particularly humpback whales, may not only tolerate but also engage with dolphins in a social capacity.

This interspecies dynamic adds a new dimension to marine mammal social ecology and could point to cultural elements in whale and dolphin societies. The playfulness, cooperation and apparent enjoyment observed in many interactions reflect advanced cognitive and emotional capabilities.

The study also demonstrates the power of new technologies and community science. Social media and drones proved invaluable for collecting a range of diverse behavioural data that traditional surveys might miss.

Social media data has limitations, such as geographic and observer bias caused by different angles, heights, equipment and frequency of use of social media. But it does complement other data and helps uncover previously unknown behaviours.

Whales and dolphins don’t just coexist but also seek each other out. Future studies incorporating acoustic recordings and longer observation periods could further unravel the motivations and meanings behind these fascinating encounters.

The Conversation

Olaf Meynecke receives funding from the Whales and Climate Research Program through a private, charitable trust and is a board member of the not for profit organisation Humpbacks and Highrises Inc.

ref. Whales and dolphins regularly hang out with each other – new study – https://theconversation.com/whales-and-dolphins-regularly-hang-out-with-each-other-new-study-260196

70 years of data show extreme heat is already wiping out tropical bird populations

Source: The Conversation – Global Perspectives – By James Watson, Professor in Conservation Science, School of the Environment, The University of Queensland

DeAgostini/Getty Images

Human-driven climate change threatens many species, including birds. Most studies on this topic focus on long-term climate trends, such as gradual rises in average temperatures or shifts in rainfall patterns. But extreme weather events are becoming more common and intense, so they warrant further attention.

Our new research shows extreme heat is having a particularly severe effect on tropical birds. We found increased exposure to extreme heat has reduced bird populations in tropical regions by 25–38% since 1950.

This is not just a temporary dip – it’s a long-term, cumulative effect that continues to build as the planet warms.

Our research helps explain why bird numbers are falling even in wild places relatively untouched by humans, such as some very remote protected tropical forests. It underscores the urgent need to reduce greenhouse gas emissions, to conserve the remaining biodiversity.

Digging into huge global datasets

We analysed data from long-term monitoring of more than 3,000 bird populations worldwide between 1950 and 2020. This dataset captures more than 90,000 scientific observations.

Although there are some gaps, the dataset offers an unmatched view of how bird populations have changed over time. Some parts of the world such as western Europe and North America were better represented than others, but all continents were covered.

We matched this bird data with detailed daily weather records from a global climate database that stretches back to 1940. This allowed us to track how bird populations responded to specific changes in daily temperatures and rainfall, including extreme heat.

We also looked at average yearly temperatures, total annual rainfall, and episodes of unusually heavy rainfall.

Using another dataset that reflects human industrial activity over time, we accounted for human pressures such as land development and human population density.

By combining all these sources of data, we created computer models to evaluate how climate factors and human impacts influence bird population growth.

Our research confirmed the work of other climate scientists showing extreme heat events have increased dramatically over the past 70 years, especially near the equator.

Birds in tropical regions are now experiencing dangerously hot days about ten times more often than they did in the past.

A chart showing the number of very hot days per year over time for the tropics (steep increase), subtropics and extratropics
Tropical birds have experienced a 10-fold increase in exposure to extreme heat over the past 60 years.
Kotz, M. et al. (2025) Nature Ecology & Evolution

What we found: extreme heat is the biggest climate threat to birds

While changes in average temperature and rainfall do affect birds, we found the increasing number of dangerously hot days had the greatest effect – especially in tropical regions.

This is a major concern because tropical birds often have small home ranges and are highly specialised in terms of the habitats and climates they persist in. In many cases tropical birds exist within a small range of heat tolerance.

At temperatures beyond a bird’s limit of endurance, they go into hyperthermia, where their body temperature rises uncontrollably. In this state, birds may adopt a drooped-wing posture to expose more skin for heat loss, hold their beaks open and pant rapidly, spread their feathers, and become lethargic or disoriented. In severe cases, they lose coordination, fall from perches, or even collapse unconscious.

Side profile of a black-collared barbet (_Lybius torquatus_) resting on a branch, The Panhandle, Okavango Delta, Botswana.
A black-collared barbet (Lybius torquatus) from Botswana.
Sergey Dereliev

If they survive the experience, they can suffer long-term damage such as heat-induced organ failure and reduced reproductive capacity. Heat exposure reduces breeding success by lowering adult body condition and reducing time spent foraging – because the birds must rest or seek shade during the hottest hours.

It also causes heat stress in eggs and nestlings. In extreme events, nestlings may die from hyperthermia, or parents may abandon nests to save themselves.

Heat also increases a bird’s demand for water — not because they sweat (birds lack sweat glands) but because they lose water rapidly through evaporative cooling. This happens mainly via panting (respiratory evaporation) and, in some species, gular fluttering (rapid vibration of throat skin to increase airflow), as well as evaporation through the skin. As temperatures climb, these processes accelerate, causing significant dehydration unless birds can drink more frequently or access moister food.

Our study found that across tropical areas, the impact of climate change on birds is perhaps even greater now than the impact of direct human activities such as logging, mining or farming. This is not to say habitat destruction due to these activities is not a serious issue – it clearly is a major concern to tropical biodiversity. But our study highlights the challenges climate change is already bringing to birds in tropical regions.

Infographic describing how birds are impacted by heat extremes
Extreme heat is bad for birds in more than one way.
James Watson, Maximilian Kotz and Tatsuya Amano with icons from Flaticon, design by Canva.

A clear warning

Our research highlights the importance of focusing not just on average climate trends, but also on extreme events. Heatwaves are no longer rare, isolated incidents – they are becoming a regular part of life in many parts of the world.

If climate change continues unchecked, tropical birds – and likely many other animals and plants – will face increasing threats to their survival. Change may be too fast and too extreme for many species to adapt.

And as tropical regions host a huge share of the world’s biodiversity, including nearly half of all bird species, the ripple effects could be far-reaching.

Conservation strategies must take this into account. Protecting habitats from human industrial development remains important, but it’s no longer enough on its own. Proactive action to help species adapt to climate change needs to be part of wildlife protection plans – especially in the tropics.

Ultimately if we are to preserve global biodiversity, slowing down and eventually reversing climate change is essential. That means cutting greenhouse gas emissions, investing in ways to draw down existing carbon dioxide levels, and supporting policies that reduce our impact on the planet. The fate of tropical birds – and countless other species – depends on it.

Tropical bird population declined by one-third since 1980 due to climate change, featuring the study’s lead author Maximilian Kotz (Potsdam Institute for Climate Impact Research)

The Conversation

James Watson has received funding from the Australian Research Council, National Environmental Science Program, South Australia’s Department of Environment and Water, Queensland’s Department of Environment, Science and Innovation as well as from Bush Heritage Australia, Queensland Conservation Council, Australian Conservation Foundation, The Wilderness Society and Birdlife Australia. He serves on the scientific committee of BirdLife Australia and has a long-term scientific relationship with Bush Heritage Australia and Wildlife Conservation Society. He serves on the Queensland government’s Land Restoration Fund’s Investment Panel as the Deputy Chair.

Maximilian Kotz receives funding from European Union’s Horizon 2020 research and innovation programme under a Marie Sklodowska-Curie grant.

Tatsuya Amano receives funding from the Australian Research Council Future Fellowship and Discovery Project.

ref. 70 years of data show extreme heat is already wiping out tropical bird populations – https://theconversation.com/70-years-of-data-show-extreme-heat-is-already-wiping-out-tropical-bird-populations-259892

How can you be sure your clothing has been produced ethically?

Source: The Conversation – Global Perspectives – By Aayushi Badhwar, Lecturer in Enterprise and Technology, RMIT University

Naomi Rahim/Getty Images/Canva

Today’s consumers are swimming in a sea of information. Products are marketed with big, bold words such as “sustainable”, “ethical” and “organic”. They sound good, they catch our attention, and they make us feel better about what we buy.

The reality is, in today’s market, figuring out which claims are true is no easy task.

One big reason is greenwashing, when brands use these buzzwords to sell products without living up to what the words actually mean. In fashion especially, these terms are thrown around so often that their meaning has been watered down. Instead of being about genuine change, they are often just a sales tool.

So, how can you know what to look out for?

Who should take responsibility for green claims?

Greenwashing takes many forms. Sometimes brands know they are misleading; this is direct greenwashing. Other times, it’s indirect, when brands simply do not know the full story of their own supply chains. A T-shirt, for example, might start as raw cotton in one country, get processed into fabric in another, sewn into a garment, and then shipped overseas for sale.

At each stage, there are different suppliers, factories and workers. The brand has limited visibility over what happens in these tiers. When a brand claims it produces ethically, but does not, that is greenwashing. If it involves exploitation or forced labour, it then becomes modern slavery, turning greenwashing into something more dangerous.

This raises a big question: who is responsible? The obvious answer is the brands. They design, order, and sell the products, and they profit from them. Consumers are paying for these goods, so they should have access to credible information, not just vague claims or nice-sounding labels.

The fashion industry is constantly in the spotlight for problems in its supply chains. Stories about poor working conditions, environmental damage, and lack of transparency pop up all the time. But just like a viral trend on social media, the attention often fades quickly, and people move on to the next story.

Certifications aren’t perfect

There are many certifications in the fashion industry trying to help, but they are not foolproof. A label might promise ethical sourcing, but that does not guarantee transparency or prove that every step was ethical.

A large portion of China’s cotton comes from the Xinjiang region, which has long been linked to forced labour; concerns were highlighted in a United Nations report in 2022. Another example is deforestation in Brazil, where cotton from affected areas was certified under the “Better Cotton” scheme. Many major brands – like ASICS producing the Australian Olympic uniforms – have faced scrutiny for sourcing cotton from controversial regions.

Tracing global supply chains is hard. But the responsibility does not disappear just because it’s complicated.

In Australia, the Modern Slavery Act took effect in January 2019 to tackle issues such as forced labour and exploitation. Penalties include heavy fines or jail time.

However, there is a major loophole, as only companies with an annual revenue over A$100 million are required to report under the act. For big corporations, even if they are caught, the penalty can be tiny compared to the profits they have made.

This is not just an Australian problem, it’s global. For example, luxury brand Dior was placed under judicial administration after being found negligent for failing to act against worker exploitation in its subcontracted supply chain in Italy. The pattern is often the same; a company gets accused, sometimes even fined, but the cost is minimal compared to their annual revenue, so it’s barely a setback.

Is there a role for government?

So, should the responsibility rest only with brands? Not entirely. Governments also benefit from these companies through taxes and trade. They profit indirectly when the companies profit, and they benefit from the jobs these companies provide.

A stronger approach would involve government bodies and brands working with supply chain mapping companies, such as Textile Genesis, TrusTrace or FibreTrace. These platforms, often powered by blockchain and artificial intelligence, track a product through every stage of production.

Blockchain – which uses a decentralised database – can be a game changer.

Unlike websites or paper trails, blockchain data cannot be altered without leaving trace. Once recorded, the information is permanent, and it can be shared across manufacturers, brands and government bodies to maintain real-time disclosure.

When products enter a country, the ethical claims behind them could be verified in real time, instead of relying on brands to respond after an allegation is made.

The upfront cost is high and adoption might be slow. But in the long run it could save money on compliance, audits and damage control, while also building consumer trust.

Brands would still make profits, but consumers would have the confidence the products they are buying live up to the claims. Instead of government agencies being passive players, they would actively enforce that products meet the standards consumers expect.

In short, brands need to be held accountable, but so do governments. Greenwashing, modern slavery, and unethical sourcing will keep slipping through the cracks, unless they both work together.

The tools to make the fashion industry more transparent and honest already exist; it’s just a matter of using them.

The Conversation

Aayushi Badhwar does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. How can you be sure your clothing has been produced ethically? – https://theconversation.com/how-can-you-be-sure-your-clothing-has-been-produced-ethically-262800

Ozempic and other weight-loss drugs linked to rare but serious eye conditions

Source: The Conversation – Global Perspectives – By Flora Hui, Research Fellow, Centre for Eye Research Australia and Honorary Fellow, Department of Surgery (Ophthalmology), The University of Melbourne

Drugs such as Ozempic, Wegovy and Mounjaro (known as semaglutide and tirzepatide) have changed the way clinicians manage diabetes and obesity around the world.

Collectively known as GLP-1 agonists, these drugs mimic the hormone GLP-1. This limits both hunger and interest in food, helping users lose weight, and helps control blood sugar levels.

But two new studies published today show that people taking these drugs may have a small increased risk of serious eye conditions and vision loss.

Here’s what you need to know if you’re taking or considering these medications.

What damage can occur?

Non-arteritic anterior ischaemic optic neuropathy, or NAION, is a rare but devastating eye condition that occurs when blood flow to the optic nerve is suddenly reduced or blocked. It’s also called an “eye stroke”.

The exact cause of NAION remains unclear and there are no current treatments available. People with diabetes are at increased risk of developing NAION.

Unlike other eye conditions that develop gradually, NAION causes a sudden, painless loss of vision. Patients typically notice the condition when they wake up and discover they’ve lost vision in one eye.

Vision tends to worsen over a couple of weeks and slowly stabilises. Recovery of vision is variable, but around 70% of people do not experience improvement in their vision.

What has previous research shown?

A previous study from 2024 found participants prescribed semaglutide for diabetes were four times more likely to develop NAION. For those taking it for weight loss, the risk was almost eight times higher.

In June, the European Medicines Agency concluded NAION represented a “very rare” side effect of semaglutide medications: a one in 10,000 chance. In a first for medicines regulators, the agency now requires product labels to include NAION as a documented risk.

However the recent studies suggest the risks may be lower than we first thought.

In addition to NAION, there is also evidence to suggest GLP-1 drugs can worsen diabetic eye disease, also known as diabetic retinopathy. This occurs when high blood sugar levels damage the small blood vessels in the retina, which can lead to vision loss.

It may sound counter-intuitive, but rapid blood sugar reductions can also destabilise the fragile blood vessels in the retina and lead to bleeding.

What do the new studies say?

Two newly published studies investigated people with type 2 diabetes living in the United States over two years. The studies looked at the medical records of 159,000 to 185,000 people.

One study found semaglutide or tirzepatide was associated with a more modest risk of developing NAION than previously thought. Of 159,000 people with type 2 diabetes who were taking these drugs, 35 people (0.04%) developed NAION, compared with 19 patients (0.02%) in the comparison group.

The researchers also found an increased risk of developing “other optic nerve disorders”. However, it’s unclear what kind of optic nerve disorders this includes, as the medical record codes used didn’t specify.

Counter to this, the second study did not find an increased risk of NAION among those taking GLP-1 drugs.

However, the researchers found a small increase in the number of people developing diabetic retinopathy in those prescribed GLP-1 drugs.

But overall, participants on GLP-1 drugs experienced fewer sight-threatening complications related to their diabetic retinopathy and required less invasive eye treatments compared to the group taking other diabetes medications.

Further studies are still needed to understand how GLP-1 drugs can lead to eye complications. A current, five-year clinical trial is studying the long-term effects of semaglutides and diabetic eye disease in 1,500 people, which should tell us more about the ocular risks in the future.

What does this mean for people taking GLP-1 drugs?

NAION is a serious condition. But we need to strike a balance between these (and other) risks and the benefits of GLP-1 medications in diabetes care, obesity treatment, reducing heart attack risks and extending lives.

The key lies in informed decision-making and identifying different levels of risk.

People with multiple NAION risk factors – such as sleep apnoea, high blood pressure and diabetes – should undergo careful consideration with their treating doctor before starting these medications.

“Crowded” optic nerve heads are also a risk factor for NAION. This is an anatomical feature where blood vessels at the optic nerve head are tightly packed together. People with crowded optic nerve heads should also undergo careful consideration before starting GLP-1 medications.

Although NAION can strike without warning, regular comprehensive eye examinations with your optometrist or ophthalmologist still serve important purposes. They can detect other drug-related eye problems, including worsening diabetic retinopathy, and can identify patients with crowded optic nerve heads. It’s also important to tell them if you are taking GLP-1 medications so they can keep a close watch on your eye health.

Emerging research also suggests that improving your heart health might help reduce risks of developing NAION. This includes proper management of high blood pressure, diabetes and cholesterol – all conditions that compromise the small blood vessels feeding the optic nerve.

Studies also show patients with heart conditions who better adhere to their medication prescriptions have lower risks of NAION than those who don’t.

Doctors should discuss NAION risks during prescribing decisions and work with eye care providers to monitor regularly for diabetic eye disease. Patients need clear instructions to seek immediate medical attention for sudden vision loss and the need for regular eye examinations.

Aggressive treatment of sleep apnoea and other heart conditions may also help reduce NAION risks. But for now, there remains an ongoing need for more research to understand how GLP-1 medications can affect the eye.

The Conversation

Pete A Williams has received past funding from Novo Nordisk Fonden (Foundation) for glaucoma neuroprotection research and is involved in, but does not directly receive funds from, a Novo Nordisk Fonden-funded clinical trial for glaucoma neuroprotection. Novo Nordisk Fonden has no role in the planning, execution, or data analysis of these studies. Novo Nordisk Fonden owns Novo Holdings A/S, which owns and controls Novo Nordisk A/S, the pharmaceutical company that makes Ozempic and Wegovy.

Flora Hui does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. Ozempic and other weight-loss drugs linked to rare but serious eye conditions – https://theconversation.com/ozempic-and-other-weight-loss-drugs-linked-to-rare-but-serious-eye-conditions-262874

What should I eat (and avoid) while breastfeeding? How does my diet affect baby’s milk?

Source: The Conversation – Global Perspectives – By Therese O’Sullivan, Associate Professor in Nutrition and Dietetics, Edith Cowan University

Natalia Lebedinskaia/Getty Images

Many people are familiar with the saying that a woman is “eating for two” during pregnancy. Although this is an exaggeration, nutritional needs do certainly increase during pregnancy to support the growing baby.

But what’s perhaps less known is that energy needs are actually even slightly higher during breastfeeding than during pregnancy.

Human breastmilk is a dynamic liquid and its composition (including carbohydrates, fats, proteins, vitamins and minerals) varies over the entire breastfeeding period, and even between feeds.

It can change depending on what mum is eating, environmental factors, and what the baby needs, through a biofeedback system (sometimes called “baby backwash”). For example, if a baby is starting to get sick, breastmilk will adjust to include more leukocytes, immune cells that fight infection.

So what should breastfeeding women be eating? And how does a mother’s diet influence the nutritional makeup of her milk?

Nutritional needs increase during breastfeeding

Fully breastfeeding mums can produce around 800 millilitres of milk a day in the first six months after birth, which has an energy content of roughly 3 kilojoules per gram.

Even factoring in using up excess fat stored during pregnancy, mums still need on average an extra 2,000 kilojoules to support milk production. This is roughly equivalent to adding a cheese sandwich, a handful of nuts and a banana on top of normal dietary intake.

Interestingly, requirements don’t drop off after the baby starts solids. In the second six months, milk production is thought to drop to an average of 600ml per day, as babies start to eat solid foods. But because maternal fat stores deplete by this stage, additional energy requirements remain similar.

Some nutrients are particularly important during breastfeeding, including protein, calcium, iron, iodine and vitamins.

For example, compared with a non-pregnant, non-breastfeeding woman, protein requirements increase by almost half when breastfeeding (from 0.75 grams to 1.1 grams per kg of body weight per day).

Meanwhile, iodine requirements almost double (from 150 micrograms per day to 270 micrograms per day). Iodine is important for thyroid function, and can impact baby’s growth and brain development.

It’s important women who are breastfeeding eat a variety of foods, including:

  • high-protein foods (meat, fish, eggs, nuts, seeds, soy-based protein such as tofu and tempeh, legumes such as chickpeas, baked beans and lentils)
  • dairy foods or alternatives (for dairy alternatives, check calcium is included)
  • whole grains
  • fruits and vegetables.

While making all that milk, drinking more water also becomes extremely important. Thirst is a good guide, but around 2.5 litres per day is generally recommended, or more if it’s hot or with exercise.

Is there anything I shouldn’t be eating?

What a mum consumes can pass into her breastmilk. For example, in one study, babies whose mothers drank small amounts of carrot juice while breastfeeding were more accepting of cereal flavoured with carrot juice compared with a control group of babies whose mothers drank water.

It’s therefore important to limit alcohol and caffeine, which can also pass though to the baby. No alcohol is the safest choice, but if you’re planning to have a drink, tools such as the Feed Safe app can be used to estimate when your breastmilk should be free of alcohol.

Up to 200mg of caffeine per day (equivalent to roughly a cup of brewed coffee, an energy or cola drink, or four cups of tea) is considered safe for breastfeeding.

Breastfeeding mums don’t need to take any particular foods out of their diet to prevent allergies in their baby. In fact, experts believe babies exposed to common allergens via breast milk could be less likely to develop allergies to these foods, however we need more research into this question.

Although relatively uncommon, babies can be allergic or intolerant to certain aspects of their mothers’ diet when breastfeeding. They may react in the form of colic or wind, reflux, mucus or blood in their poo, eczema or rash, or appear to be in pain.

In these cases, mum’s diet may need adjustment. The most common culprits include cows’ milk (the protein, not the lactose component), soy and egg.

It’s recommended to remove suspected foods from the diet for a minimum of three weeks. This should ideally be done with supervision from an Accredited Practising Dietitian who specialises in allergy, to ensure the mother’s nutritional needs continue to be met.

4 tips for breastfeeding mums

  1. it’s a good idea to get a blood test to check your vitamin D and iron levels – these can be depleted over pregnancy and are important for breastfeeding. If your levels are low, you can discuss options with your doctor

  2. iodine requirements are so much higher in breastfeeding that an iodine supplement of 150 micrograms a day is recommended to support infant growth and neurodevelopment

  3. have a variety of nutritious snacks that can be eaten with one hand for those late-night feeds, such as peeled boiled eggs, a peanut butter sandwich on wholegrain bread, or avocado and cheese on a rice cake. My personal favourite is homemade rocky road with dark chocolate, nuts, seeds and dried fruit

  4. keep a drink bottle with water nearby when breastfeeding.

Rocky road.
The author’s home-made rocky road, which she gives as a gift to friends with new babies.
Therese O’Sullivan/Author provided

If you’re considering a gift for a family with a new baby, remember new parents’ personal needs often take a back seat when bub arrives, including eating well. Consider a hearty frozen meal, muffins with oats and nuts, a nice stainless steel water bottle, gourmet trail mix or even some homemade rocky road.

The Conversation

Therese O’Sullivan has previously received funding from the Stan Perron Charitable Foundation and the Department of Health Western Australia for a project on antenatal colostrum expressing.

ref. What should I eat (and avoid) while breastfeeding? How does my diet affect baby’s milk? – https://theconversation.com/what-should-i-eat-and-avoid-while-breastfeeding-how-does-my-diet-affect-babys-milk-260423

Australia to recognise Palestine state next month at the United Nations

Source: The Conversation – Global Perspectives – By Michelle Grattan, Professorial Fellow, University of Canberra

Prime Minister Anthony Albanese has announced Australia will recognise Palestine as a state at the United Nations leaders’ week in late September.

Unlike some other countries, the government has put no conditions on the recognition, relying on assurances received from the Palestinian Authority, the current Palestinian governing body in the West Bank.

Announcing the decision on Monday, Albanese said he had spoken to Israeli Prime Minister Benjamin Netanyahu last Thursday. In what Albanese said was a long call, Netanyahu argued the case against the proposed Australian action.

“I put the argument to him that we need a political solution, not a military one, because a military response alone has seen the devastation in Gaza, and that has contributed to the massive concern that we see from the international community,” Albanese said.

Albanese told a joint news conference with Foreign Minister Penny Wong “a two-state solution is humanity’s best hope to break the cycle of violence in the Middle East and to bring an end to the conflict, suffering and starvation in Gaza”.

Asked whether this was a symbolic gesture, Albanese said, “This is a practical contribution towards building momentum. This is not Australia acting alone. What we are seeing is a range of countries engaging in detailed dialogue.”

Albanese said that over the past fortnight, he had discussed the issue with UK Prime Minister Keir Starmer, French President Emmanuel Macron, New Zealand Prime Minister Chris Luxon and Japanese Prime Minister Shigeru Ishiba.

He also had a call last week with the Palestinian Authority President Mahmoud Abbas.

Albanese said the Palestinian Authority had committed to there being no role for Hamas in a Palestinian state and reaffirmed it recognised Israel’s right to exist, as well as making other pledges.

Shadow Defence Minister Angus Taylor said there is a risk the decision would be rewarding Hamas for its attacks on Israel on October 7 2023.

When asked earlier about such criticism, Albanese said “Hamas don’t support two states”.

“This is an opportunity to isolate Hamas, that has been forged by the very clear statements of the Palestinian Authority on June 10, and the very clear statements of the Arab League,” he said.

Before the announcement, Netanyahu strongly condemned the move.

He said it was “shameful” and “disappointing” that European countries and Australia would “march into that rabbit hole” and buy “this canard”. He made it clear Israel would not be deterred.

Asked about Australia and other countries moving to recognition, he said, “Well, first of all, those who say that Israel has a right to defend itself are also saying, ‘but don’t exercise that right’.”

He said Israel was applying force judiciously and “they know it”.

“They know what they would do if right next to Melbourne or right next to Sydney you had this horrific attack. I think you would do, at least what we’re doing – probably maybe not as efficiently and as precisely as we’re doing it.”

The Albanese government’s decision, which was reported to a cabinet meeting early Monday, followed years of pressure within the Labor party which has ramped up dramatically in recent months.

Wong spoke at the weekend to US Secretary of State Marco Rubio about Australia’s proposed course.

The Executive Council of Australian Jewry said in a statement about the announcement: “Israel will feel wronged and abandoned by a longstanding ally. The Palestinian Authority will feel that a huge diplomatic prize has been dropped in its lap, despite its consistent failures to reform, democratise and agree to peaceful coexistence alongside a Jewish state. Hamas and other Islamist groups will see that barbarity on a grand scale can lead to desired political transformation”.

The Conversation

Michelle Grattan does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. Australia to recognise Palestine state next month at the United Nations – https://theconversation.com/australia-to-recognise-palestine-state-next-month-at-the-united-nations-262602

This isn’t how wars are ended − a veteran diplomat explains how Trump-Putin summit is amateurish and politically driven

Source: The Conversation – USA – By Donald Heflin, Executive Director of the Edward R. Murrow Center and Senior Fellow of Diplomatic Practice, The Fletcher School, Tufts University

U.S. President Donald Trump and Russian President Vladimir Putin will meet in Alaska on Aug. 15, 2025. Here, they arrive for a group photo at the G20 Summit in Osaka on June 28, 2019. Brendan Smialowski/AFP via Getty Images Brendan Smialowski / AFP via Getty Images

A hastily arranged summit between President Donald Trump and Russian President Vladimir Putin is set for Aug. 15, 2025, in Alaska, where the two leaders will discuss a peace deal between Russia and Ukraine. Ukrainian President Volodymyr Zelenskyy will not attend, barring a last-minute change. The Conversation’s politics editor Naomi Schalit interviewed longtime diplomat Donald Heflin, now teaching at Tufts University’s Fletcher School, to get his perspective on the unconventional meeting and why it’s likely to produce, as he says, a photograph and a statement, but not a peace deal.

How do wars end?

Wars end for three reasons. One is that both sides get exhausted and decide to make peace. The second, which is more common: One side gets exhausted and raises its hand and says, “Yeah, we’re ready to come to the peace table.”

And then the third is – we’ve seen this happen in the Mideast – outside forces like the U.S. or Europe come in and say, “That’s enough. We’re imposing our will from the outside. You guys stop this.”

What we’ve seen in the Russia-Ukraine situation is neither side has shown a real willingness to go to the conference table and give up territory.

So the fighting continues. And the role that Trump and his administration are playing right now is that third possibility, an outside power comes in and says, “Enough.”

Now you have to look at Russia. Russia is maybe a former superpower, but a power, and it’s got nuclear arms and it’s got a big army. This is not some small, Middle Eastern country that the United States can completely dominate. They’re nearly a peer. So can you really impose your will on them and get them to come to the conference table in seriousness if they don’t want to? I kind of doubt it.

Two people standing on rubble next to bombed-out multistory buildings.
Residents of Kramatorsk, Ukraine, step out of their car amid residential buildings bombed by Russian forces on Aug. 10, 2025.
Pierre Crom/Getty Images

How does this upcoming Trump-Putin meeting fit into the history of peace negotiations?

The analogy a lot of people are using is the Munich Conference in 1938, where Great Britain met with Hitler’s Germany. I don’t like to make comparisons to Nazism or Hitler’s Germany. Those guys started World War II and perpetrated the Holocaust and killed 30 or 40 million people. It’s hard to compare anything to that.

But in diplomatic terms, we go back to 1938. Germany said, “Listen, we have all these German citizens living in this new country of Czechoslovakia. They’re not being treated right. We want them to become part of Germany.” And they were poised to invade.

The prime minister of Great Britain, Neville Chamberlain, went and met with Hitler in Munich and came up with an agreement by which the German parts of Czechoslovakia would become part of Germany. And that would be it. That would be all that Germany would ask for, and the West gave some kind of light security guarantees.

Czechoslovakia wasn’t there. This was a peace imposed on them.

And sure enough, you know, within a year or two, Germany was saying, “No, we want all of Czechoslovakia. And, P.S., we want Poland.” And thus World War II started.

Two men shaking hands; one wearing a military uniform with a Nazi swastika on an armband.
German dictator Adolf Hitler, right, shakes hands with British Prime Minister Neville Chamberlain during their meeting at Godesberg, Germany, on Sept. 23, 1938.
New York Times Co./Getty Images

Can you spell out the comparisons further?

Czechoslovakia wasn’t at the table. Ukraine’s not at the table.

Again, I’m not sure I want to compare Putin to Hitler, but he is a strongman authoritarian president with a big military.

Security guarantees were given to Czechoslavakia and not honored. The West gave Ukraine security guarantees when that country gave up its nuclear weapons in 1994. We told them, “If you’re going to be brave and give up your nuclear weapons, we’ll make sure you’re never invaded.” And they’ve been invaded twice since then, in 2014 and 2022. The West didn’t step up.

So history would tell us that the possibilities for a lasting peace coming out of this summit are pretty low.

What kind of expertise is required in negotiating a peace deal?

Here’s what usually happens in most countries that have a big foreign policy or national security establishment, and even in some smaller countries.

The political leaders come up with their policy goal, what they want to achieve.

And then they tell the career civil servants and foreign service officers and military people, “This is what we want to get at the negotiating table. How do we do that?”

And then the experts say, “Oh, we do this and we do that, and we’ll assign staff to work it out. We’ll work with our Russian counterparts and try to narrow the issues down, and we’ll come up with numbers and maps.”

With all the replacement of personnel since the inauguration, the U.S. not only has a new group of political appointees – including some, like Marco Rubio, who, generally speaking, know what they’re doing in terms of national security – but also many who don’t know what they’re doing. They’ve also fired the senior level of civil servants and foreign service officers, and a lot of the mid-levels are leaving, so that expertise isn’t there.

That’s a real problem. The U.S. national security establishment is increasingly being run by the B team – at best.

How will this be a problem when Trump meets Putin?

You have two leaders of two big countries like this, they usually don’t meet on a few days’ notice. It would have to be a real crisis.

This meeting could happen two or three weeks from now as easily as it could this week.

And if that happened, you would have a chance to prepare. You’d have a chance to get all kinds of documents in front of the American participants. You would meet with your Russian counterparts. You’d meet with Ukrainian counterparts, maybe some of the Western European countries. And when the two sides sat down at the table, it would be very professional.

They would have very similar briefing papers in front of them. The issues would be narrowed down.

None of that’s going to happen in Alaska. It’s going to be two political leaders meeting and deciding things, often driven by political considerations, but without any real idea of whether they can really be implemented or how they could be implemented.

Could a peace deal possibly be enforced?

Again, the situation is kind of haunted by the West never enforcing security guarantees promised in 1994. So I’m not sure how well this could be enforced.

Historically, Russia and Ukraine were always linked up, and that’s the problem. What’s Putin’s bottom line? Would he give up Crimea? No. Would he give up the part of eastern Ukraine that de facto had been taken over by Russia before this war even started? Probably not. Would he give up what they’ve gained since then? OK, maybe.

Then let’s put ourselves in Ukraine’s shoes. Will they want to give up Crimea? They say, “No.” Do they want to give up any of the eastern part of the country? They say, “No.”

I’m curious what your colleagues in the diplomatic world are saying about this upcoming meeting.

People who understand the process of diplomacy think that this is very amateurish and is unlikely to yield real results that are enforceable. It will yield some kind of statement and a photo of Trump and Putin shaking hands. There will be people who believe that this will solve the problem. It won’t.

The Conversation

Donald Heflin does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. This isn’t how wars are ended − a veteran diplomat explains how Trump-Putin summit is amateurish and politically driven – https://theconversation.com/this-isnt-how-wars-are-ended-a-veteran-diplomat-explains-how-trump-putin-summit-is-amateurish-and-politically-driven-262995