Category: The Conversation

Source: The Conversation – UK – By Graham Finlayson, Professor of Psychobiology, University of Leeds

Ultra-processed foods (UPFs) have become public enemy number one in nutrition debates. From dementia to obesity and an epidemic of “food addiction”, these factory-made products, including crisps, ready meals, fizzy drinks and packaged snacks, are blamed for a wide range of modern health problems. Some experts argue that they’re “specifically formulated and aggressively marketed to maximise consumption and corporate profits”, hijacking our brain’s reward systems to make us eat beyond our needs.

Policymakers have proposed bold interventions: warning labels, marketing restrictions, taxes, even outright bans near schools. But how much of this urgency is based on solid evidence?

My colleagues and I wanted to step back and ask: what actually makes people like a food? And what drives them to overeat – not just enjoy it, but keep eating after hunger has passed? We studied more than 3,000 UK adults and their responses to over 400 everyday foods. What we found challenges the simplistic UPF narrative and offers a more nuanced way forward.

Two ideas often get blurred in nutrition discourse: liking a food and hedonic overeating (eating for pleasure rather than hunger). Liking is about taste. Hedonic overeating is about continuing to eat because the food feels good. They’re related, but not identical. Many people like porridge but rarely binge on it. Chocolate, biscuits and ice cream, on the other hand, top both lists.

We conducted three large online studies where participants rated photos of unbranded food portions for how much they liked them and how likely they were to overeat them. The foods were recognisable items from a typical UK shopping basket: jacket potatoes, apples, noodles, cottage pie, custard creams – more than 400 in total.

We then compared these responses with three things: the foods’ nutritional content (fat, sugar, fibre, energy density), their classification as ultra-processed by the widely used Nova system – a food classification method that groups foods by the extent and purpose of their processing – and how people perceived them (sweet, fatty, processed, healthy and so on).

Perception power

Some findings were expected: people liked foods they ate often, and calorie-dense foods were more likely to lead to overeating.

But the more surprising insight came from the role of beliefs and perceptions. Nutrient content mattered – people rated high-fat, high-carb foods as more enjoyable, and low-fibre, high-calorie foods as more “bingeable”. But what people believed about the food also mattered, a lot.

Perceiving a food as sweet, fatty or highly processed increased the likelihood of overeating, regardless of its actual nutritional content. Foods believed to be bitter or high in fibre had the opposite effect.

In one survey, we could predict 78% of the variation in people’s likelihood of overeating by combining nutrient data (41%) with beliefs about the food and its sensory qualities (another 38%).

In short: how we think about food affects how we eat it, just as much as what’s actually in it.

This brings us to ultra-processed foods. Despite the intense scrutiny, classifying a food as “ultra-processed” added very little to our predictive models.

Once we accounted for nutrient content and food perceptions, the Nova classification explained less than 2% of the variation in liking and just 4% in overeating.

That’s not to say all UPFs are harmless. Many are high in calories, low in fibre and easy to overconsume. But the UPF label is a blunt instrument. It lumps together sugary soft drinks with fortified cereals, protein bars with vegan meat alternatives.

Some of these products may be less healthy, but others can be helpful – especially for older adults with low appetites, people on restricted diets or those seeking convenient nutrition.

The message that all UPFs are bad oversimplifies the issue. People don’t eat based on food labels alone. They eat based on how a food tastes, how it makes them feel and how it fits with their health, social or emotional goals.

Relying on UPF labels to shape policy could backfire. Warning labels might steer people away from foods that are actually beneficial, like wholegrain cereals, or create confusion about what’s genuinely unhealthy.

Instead, we recommend a more informed, personalised approach:

• Boost food literacy: help people understand what makes food satisfying, what drives cravings, and how to recognise their personal cues for overeating.

• Reformulate with intention: design food products that are enjoyable and filling, rather than relying on bland “diet” options or ultra-palatable snacks.

• Address eating motivations: people eat for many reasons beyond hunger – for comfort, connection and pleasure. Supporting alternative habits while maximising enjoyment could reduce dependence on low-quality foods.

It’s not just about processing

Some UPFs do deserve concern. They’re calorie dense, aggressively marketed and often sold in oversized portions. But they’re not a smoking gun.

Labelling entire categories of food as bad based purely on their processing misses the complexity of eating behaviour. What drives us to eat and overeat is complicated but not beyond understanding. We now have the data and models to unpack those motivations and support people in building healthier, more satisfying diets.

Ultimately, the nutritional and sensory characteristics of food – and how we perceive them – matter more than whether something came out of a packet. If we want to encourage better eating habits, it’s time to stop demonising food groups and start focusing on the psychology behind our choices.

Graham Finlayson has received funding from Horizon Europe, UKRI and Slimming World, UK.

James Stubbs consults to Slimming World UK. He receives funding from UKRI.

– ref. Ultra-processed foods might not be the real villain in our diets – here’s what our research found – https://theconversation.com/ultra-processed-foods-might-not-be-the-real-villain-in-our-diets-heres-what-our-research-found-261867

Source: The Conversation – UK – By Shooka Bidarian, Media and Journalism Fellow, Sustainability and Climate at United Nations University Institute of Water Health and Environment, United Nations University

From arid deserts and alpine meadows to dense wetlands and temperate forests, Iran’s natural landscapes give rise to rich native wildlife. This country is home to over 8,000 species of plants, nearly 500 bird species and 194 mammals. The UN has listed 13 special ecological areas, including salt lakes and marshlands, that support huge numbers of migratory birds.

But this rich natural heritage is under growing threat. The Asiatic cheetah, once widespread across west Asia, is now confined to desert reserves in central Iran, with fewer than 50 remaining.

The Persian onager, a wild ass native to Iran’s deserts, struggles on with just 600–700 animals remaining, displaced by both water scarcity and livestock. And the Siberian crane, once a seasonal visitor, has vanished from the Iranian landscape entirely. The last known individual, a male named Omid, was last spotted over three years ago.

Iran’s accelerating biodiversity crisis is a warning sign, but it does not exist in isolation. The country’s ecosystems are under siege not only from species loss, but also from deeper, systemic environmental pressures.

Chief among these is a worsening water crisis. This is now widely recognised by researchers as a case of “water bankruptcy”, where unsustainable demand has long outstripped the country’s renewable water resources.

Due to the Iran-Iraq war, international isolation and sanctions since the 1980s, the government has driven policies to make the country’s food system more self-sufficient. They have promoted growing crops such as wheat and rice, which are water-intensive and ill-suited to Iran’s arid climate.

Today, more than 90% of Iran’s water is allocated to agriculture, primarily to grow these water-hungry crops in some of the driest parts of the country. The consequences have been stark: land degradation, the erosion of rural livelihoods and a deepening cycle of poverty and environmental decline.

Poor water governance and inappropriate farming have driven the depletion of aquifers (underground layers of porous rock saturated with groundwater) and the drying out of rivers and wetlands. This has placed mounting stress on communities and local economies.

These challenges are compounded by entrenched interests and fragmented institutions’ oversight, and bureaucracies that are competing for control of the limited water supplies. In such a landscape, meaningful reform and equitable distribution become difficult, if not impossible.

Poverty, migration and dysfunctional institutions are causing widespread food insecurity. Without coherent, transparent governance and a long-term vision for environmental stewardship, Iran’s water crisis threatens to undermine both public welfare and national economic stability.

Environmental advocacy in Iran faces formidable legal and political barriers. Civil society organisations have confidentially told us they often struggle to formally register due to restrictive state permitting systems. This limits their ability to operate independently or engage in effective community mobilisation. Meanwhile, independent conservation efforts have come under increasing scrutiny by the Iranian government.

In 2018, several conservationists from the Persian Wildlife Heritage Foundation, a not-for-profit organisation, were arrested on national security charges, despite no credible evidence. This move was widely condemned by international human rights organisations.

These arrests were central to the documentary Tears of Extinction (written and presented by one of us, Shooka Bidarian) that highlighted how, without these conservation efforts, the Asiatic cheetahs would face extinction within a few years.

From challenge to reform

The prosecutions and prolonged detentions have contributed to a chilling effect, discouraging other scientists and conservation organisations from engaging in environmental work due to fears of surveillance and reprisal. This concern was publicly echoed by Issa Kalantari, then vice-president and head of Iran’s Department of Environment, who stated that “if we knew they were spies, we would have treated them differently” and admitted the arrests caused environmental activities across the country to freeze.

Despite the severity of Iran’s environmental challenges, experts from the United Nations University and colleagues have outlined actionable reforms. These range from modernising irrigation systems and adjusting water pricing to enhancing data transparency and embracing participatory, decentralised governance.

Long-term resilience also requires adaptive planning that integrates climate variability and social vulnerability into national water strategies. These aren’t radical ideas. These approaches have been proven to work well in other water-stressed regions such as Australia.

To protect Iran’s ecosystems and ensure their survival for future generations, the country needs new approaches to environment governance. This needs to include sustained, science-led conservation, supported by international collaboration and local participation.

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Shooka Bidarian is affiliated with United Nations University and The Climate Reality Project

Mark Maslin is Pro-Vice Provost of the UCL Climate Crisis Grand Challenge and Founding Director of the UCL Centre for Sustainable Aviation. He was co-director of the London NERC Doctoral Training Partnership and is a member of the Climate Crisis Advisory Group. He is an advisor to Sheep Included Ltd, Lansons, NetZeroNow and has advised the UK Parliament. He has received grant funding from the NERC, EPSRC, ESRC, DFG, Royal Society, DIFD, BEIS, DECC, FCO, Innovate UK, Carbon Trust, UK Space Agency, European Space Agency, Research England, Wellcome Trust, Leverhulme Trust, CIFF, Sprint2020, and British Council. He has received funding from the BBC, Lancet, Laithwaites, Seventh Generation, Channel 4, JLT Re, WWF, Hermes, CAFOD, HP and Royal Institute of Chartered Surveyors.

– ref. Iran’s nature is under threat – here’s how better environmental stewardship can save it – https://theconversation.com/irans-nature-is-under-threat-heres-how-better-environmental-stewardship-can-save-it-260458

Source: The Conversation – UK – By Tom Vaughan, Lecturer in International Security, University of Leeds

In August 1945 the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki, killing more than 200,000 people, overwhelmingly civilians. Eighty years on from this slaughter – which the then US army commander and later president Dwight D. Eisenhower called “completely unnecessary” – is an apt time to ask how the world has changed since Japan’s skies lit up with atomic fire.

Many in the military as well as academics and nuclear theorists argue that a “third nuclear age” has begun. By this they mean that a new and different set of nuclear threats are emerging which fundamentally challenge the existing tenets of nuclear “deterrence”. The response, some argue, is to invest heavily in our nuclear weapons systems to secure ourselves against this new age of uncertainty.

To understand this claim, it’s worth looking back at the history of the nuclear era. Most (but not all) scholars working on “nuclear ages” accept that the first nuclear age, between 1945 and 1991, was characterised by the cold war nuclear stand-off between the world’s two nuclear armed superpowers: the US and the Soviet Union.

The second nuclear age, from 1991 to 2014, is usually understood to have started when the cold war ended. Policymakers worried about “proliferation” – the spread of nuclear weapons to new states and even non-state terrorist groups. Western policy focused on countering this process, often through military means.

The third nuclear age, which is thought to have begun in 2014, it thought to reflect a new set of challenges. This will involve the entry of more nuclear-armed states into the fray, erosion of longstanding non-proliferation and arms control agreements and the development of so-called “strategic non-nuclear weapons”. This term refers to non-nuclear technologies, including artificial intelligence (AI) command and control networks, hypersonic missiles and advanced missile defence systems.

There are fears that non-nuclear armed “adversaries” might use these systems to directly attack other states’ nuclear arsenals, undermining their ability to deliver a retaliatory nuclear strike. This is likely to pose a challenge to established practices on which the doctrine of nuclear deterrence is based.

But how much has really changed in the past decade? No new nuclear powers have emerged – the most recent was North Korea in 2006. China, often seen as the bogeyman of the third nuclear age, has had a nuclear weapons capability since 1964. AI integration into nuclear command and control systems, while extremely risky, has yet to happen.

Reliable missile defence against modern nuclear warheads is still widely considered to be technologically impossible. The impact of hypersonic missiles on the calculus of nuclear deterrence is debated, since intercontinental ballistic missiles (ICBMs) are already very fast.

In short, what’s different this time around?

Western-centric thinking

A more penetrating line of questioning is to ask about the politics underlying the idea of a third nuclear age. Ideas are never neutral, and they shape our understanding of the world. The third nuclear age concept (like that of the second nuclear age before it) came out of the US defence establishment, which was trying to understand how it could remain globally dominant against challenges to its supremacy from China.

The idea has since been filtered through academia and back into the policy world, where it has started to gain “common sense status”: as night follows day, the dawn of the third nuclear age is around the corner. But this is neither objective nor inevitable. It’s a conceptual tool for thinking about nuclear politics in a particular way.

It’s a US-centric perspective reflecting a fear that western dominance of the nuclear arena is under threat. US and allied militaries need to progressively integrate new technologies into their nuclear systems and modernise their arsenals to deal with a “more uncertain” world, ignoring the fact that massive risk and uncertainty have always been a built-in feature of nuclear deterrence strategies.

Here, the biggest threats to nuclear stability come not from the thousands of nuclear warheads held by the established nuclear weapons states, but from would-be disruptors who can threaten nuclear arsenals with non-nuclear systems – echoing old second nuclear age fears about proliferation.

This is why Iran remains a villain of the story alongside China, as we can see from the hyperbole about Iran’s “hypersonic” missile capabilities and how its behaviour gave Israel and the US the excuse to launch “counter-proliferation” strikes against its nuclear facilities in June this year.

It bears repeating that Iran is still not a nuclear-armed state. But the new emphasis placed on non-nuclear technologies in third nuclear age thinking also puts states which don’t even have nuclear programmes in the crosshairs of Iraq-style wars of aggression in the name of “counter-proliferation”.

New arms race

To be crystal clear: the nuclear world is as dangerous as ever. The problem is that third nuclear age thinking, with its focus on supposedly unprecedented disruptions, leads us to think that new solutions are necessary. “Old” ideas about nuclear disarmament become irrelevant, because the instabilities introduced by new technologies supposedly make it impossible for nuclear weapons states to give up their arsenals.

The third nuclear age becomes a conceptual stalking horse for a fresh nuclear arms race.

When the British armed forces chief Admiral Sir Tony Radakin warned of a dawning third nuclear age in December 2024, he was not making a neutral observation. He was arguing for resources to be funnelled into nuclear modernisation at the expense of welfare and healthcare programmes. Today, before any modernisation, Britain maintains a first-strike deliverable total of 31 megatons of nuclear explosive power. That’s more than 2,000 Hiroshimas’ worth of destruction.

So we should be sceptical of this concept. The threat of nuclear annihilation has been with us since August 1945 and comes – as always – from nuclear weapons and the states who operate them.

Tom Vaughan 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. The ‘third nuclear age’ is a politically motivated label that seeks to justify a renewed arms race – https://theconversation.com/the-third-nuclear-age-is-a-politically-motivated-label-that-seeks-to-justify-a-renewed-arms-race-263009

Source: The Conversation – UK – By Steve Fletcher, Professor of Ocean Policy and Economy, University of Portsmouth

The latest round of negotiations for a UN global plastics treaty has ended without a deal. After more than three years of talks, deep divisions remain. Agreement is only marginally closer than before talks began. For many countries, campaigners and observer organisations, the outcome is deeply disappointing.

After the final intense meetings which went through the night in Geneva, the chair of the intergovernmental negotiating committee that governs the treaty discussions formally closed the session on August 15 without agreement on the treaty text. This is not the end. The process has not collapsed.

However, there is no confirmed date or venue for the next round of negotiations and no mandate for formal intersessional activities. Many delegates called for a period of reflection and even a reset of the process to allow for a refreshed approach.

As in previous negotiation rounds, progress was slow. Talks were hampered by procedural ambiguity, deliberate delay tactics from fossil fuel and petrochemical countries opposing an ambitious treaty, and the sheer complexity of the issues on the table. Time ran out before a consensus could be reached.

As the talks wrap up, we reflect on three aspects that contributed to this ongoing deadlock:

1. Chair’s efforts fell short

Ambassador Luis Vayas Valdivieso took a more active role than in earlier sessions, pushing the pace and producing two draft treaty texts to focus debate. The first draft omitted key provisions, including limits on plastic production, global rules for regulating plastic products, controls on harmful chemicals and strong financing arrangements.

Many high-ambition countries pushing for strong measures and outcomes, rejected the first draft as imbalanced, unambitious and unfit for further discussion. A second draft, issued just before 1am on the final night after intense consultations, included some improvements but still left out these core elements. Many nations again saw it as one-sided, tilted towards the demands of lower-ambition countries and petrostates.

2. Entrenched positions remain

Throughout the negotiations, lower-ambition states gave little ground. They refused to compromise on their “red lines” while expecting others to give up on theirs.

This repeated familiar arguments over the purpose and scope of the treaty, despite these having been outlined in the UN mandate to deliver the treaty three years ago. Many believe a different approach is needed that focuses more time on points of disagreement, rigorously tests opposing arguments, and actively seeks areas of compromise.

3. Reluctance to vote

The process still relies on consensus for decision-making. In the final plenary, many delegates, particularly those with economic interests in plastics, stressed that consensus is essential. Yet over the past three years, some delegations have urged the chair to break deadlocks by moving to a vote – a rule of UN negotiations that must be applied when consensus cannot be reached.

Voting is seen as politically explosive, with serious implications for multilateralism. So far, the chair has resisted calling a vote, and higher-ambition countries have not pressed for it either, despite their repeated statements about urgency and ambition. Beyond rejecting treaty texts they considered weak, many did not use the tools available to them to push for a stronger outcome. As a result, stalemates have persisted.

The road ahead

The intersessional period – the time between now and the next formal meeting – is critical. Without a fixed date for the next stage of the process, this is the time to reset and prepare for decisive progress. One key focus must be to bridge political divides. High-ambition countries need to build broader alliances and find shared ground with those who may not fully back their vision but are open to stronger action.

Key details such as financing mechanisms, monitoring and reporting systems, and legal models for compliance should be developed now, outside formal negotiations, to save time later. And higher-ambition nations such as those in the EU, Panama, Colombia, Australia, the UK and small island states should coordinate more closely and be willing to use procedural tools such as voting when needed, even if politically uncomfortable.

The goal set by the UN in 2022 to end plastic pollution across its full life cycle is still achievable. But it will require governments to use the coming months to regroup, have frank political discussions and commit to a more decisive approach when they next meet.

The world cannot afford another round lost to procedural deadlock. The plastics crisis is worsening. The science is clear. The solutions are well known. What is missing is not knowledge, but the will to match words with binding action.

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Steve Fletcher receives funding from the World Economic Forum, Natural Environment Research Council (NERC), Economic and Social Research Council (ESRC), Aquapak Ltd, Defra, and the Flotilla Foundation. He is a member of the United Nations International Resource Panel and is the NERC Agenda Setting Fellow for Plastic Pollution.

Antaya March receives funding from the Flotilla Foundation, Defra, World Economic Forum, and the British Academy.

– ref. Three reasons plastic pollution treaty talks ended in disagreement and deadlock (but not collapse) – https://theconversation.com/three-reasons-plastic-pollution-treaty-talks-ended-in-disagreement-and-deadlock-but-not-collapse-261327