The change we want versus the system we have

A recent BBC investigation into childhood obesity in southern Italy highlighted a paradox with implications far beyond food. Children in the region that gave the world the Mediterranean Diet are now among the most overweight in Europe. The scientific evidence supporting the Diet remains strong, its principles are widely recognised and its cultural significance is protected. Yet its influence over everyday eating seems to have weakened.

Behind the obesity figures lies a harder problem: knowledge has to compete with the pressures of everyday life. Healthier choices are difficult to sustain when the surrounding environment makes unhealthy choices easier. That raises a wider question for sustainability: what happens when evidence points one way while everyday conditions favour another?

The Mediterranean Diet was never just a menu

The Mediterranean Diet is still widely presented as guidance about what individuals should eat. Sara Roversi, founder of the Future Food Institute, challenges that narrow definition. She describes it as a way of life shaped by food production, relationships, shared practices, local institutions and place, with the familiar dietary pattern as one outcome. Treating it as a menu makes its declining influence look like the result of individual choices, rather than changes to the conditions that once made this way of eating easier to sustain.

Roversi points to shared meals, seasonal and local food, domestic cooking, farming knowledge, public markets and the proximity between producers and consumers as part of that system. Such practices pass knowledge between generations while making particular foods familiar, accessible and part of everyday life. In many places, she says, they have been displaced by "speed, convenience and increasingly individualised lifestyles." The question, then, is what changed in people's lives and surroundings to make this way of eating harder to sustain.

Lost or displaced?

The investigation described the traditional Mediterranean Diet as having been lost, and depicted an Italy in which many of the conditions that sustained it have also changed. But the language of loss can make that change sound passive or inevitable. Roversi argues that consumer choice alone cannot explain the change: the choices available to people are continually shaped by economic and political decisions. "They are actively produced," she says. "Commercial incentives, pricing, marketing, retail concentration, agricultural subsidies and weak regulation all shape what is available, visible, affordable and normal." Families are still expected to make healthy choices, but they do so within environments that continually push them in another direction.

No single decision explains this shift. Businesses pursue sales and scale, retailers favour profitable products that are easy to distribute, and governments subsidise some forms of production while regulating some kinds of marketing more strongly than others. Earlier generations also chose within conditions that made certain foods and practices familiar, practical and normal. Today, working patterns, prices, advertising, retail access and infrastructure shape what is convenient and normal, while different actors have very unequal influence over what is produced and sold. Repeated over time, these forces favour speed, standardisation and individual consumption, even though no single actor may have intended the overall result.

These pressures have helped create what Roversi describes as "a fast-life model based on a very narrow idea of efficiency: saving time in the short term while externalising costs onto health, communities and ecosystems." Convenience saves time, but some costs appear elsewhere: in chronic illness and public-health spending, the loss of local producers and shared practices, and the additional energy demands associated with processing and packaging. What appears efficient within a single transaction can make the wider system more costly and less resilient.

Earlier arrangements should not be romanticised, however. The BBC reported that some parents regarded excess weight as a sign of childhood health, while feeding could express care in ways that made overconsumption harder to recognise. "Culture is not static, and not every inherited belief is beneficial," Roversi says. Practices that pass on cooking knowledge can also reproduce beliefs that make childhood obesity harder to recognise and address. That means any effort to change those beliefs will need more than evidence – it will need to be developed with the communities involved.

What Pollica has sustained

Pollica, a small municipality in the Cilento area of Campania, offers a contrasting example from within the same region. It is home to the Paideia Campus and Living Lab, operated by the Future Food Institute in partnership with the municipality and local institutions. Over more than a decade, local actors have connected school meals and food education with agriculture, farmers' markets, planning, biodiversity conservation and community participation. Pollica's experience does not prove that its local policies produced particular health outcomes. It does show that the Mediterranean Diet has not lost ground everywhere to the same extent, and that some communities retain more influence over what food is available and how their local food system develops.

"Research has accompanied a decade of public policy, allowing us to measure what happens when a community intentionally invests in its food culture over time," Roversi says. Pollica has not relied on food education alone, as it works to connect what children learn with what schools serve, what local farmers produce, where food is sold and how public space is used. A lesson about healthy eating has limited value if the canteen, the shops outside school and the wider food environment all point in another direction.

Recent research has begun to examine more closely how environment, dietary practices and health interact in Pollica and elsewhere. Under ONFOODS, the Italian food-research programme that concluded in April 2026, LAFA combined environmental, biological, dietary and lifestyle data, producing a predictive platform linking environmental conditions, nutrition and health. HOHLI examined connections between marine health, local seafood, dietary patterns and human health. Roversi says researchers have also used established tools including KIDMED and MEDAS to measure adherence to the Mediterranean Diet among different age groups. FFI remains involved in the EU-funded SWITCH project, which is testing ways to overcome barriers to healthier and more sustainable diets across six European food hubs. Together, this research looks beyond what people eat to examine the wider conditions influencing their choices.

Research can also detect changing dietary practices before their consequences reach the clinic. "The key is to monitor not only health outcomes, but the cultural and material conditions that produce them," Roversi says. Changes in shared meals, home cooking, school-food participation, local procurement and access to fresh food can provide early warning alongside measures such as BMI and blood pressure.

Pollica shows what a municipality can influence – and what remains beyond its control. Municipalities can shape school meals, procurement, markets, planning and public space, but regional and national governments control many of the taxes, subsidies and marketing rules affecting the wider food environment. Those local measures will have limited effect if policies set elsewhere continue to push the food environment in another direction. Used effectively, evidence from municipalities and communities could help regional and national governments identify where their policies support or undermine local measures, and adjust them accordingly.

Why evidence is not enough

This is where the story extends beyond food. Decades of research continue to associate adherence to the Mediterranean Diet with better cardiovascular and metabolic health. Yet the strength of that evidence has not preserved the practices and conditions on which adherence depends. Evidence can tell us about the health effects of a particular way of eating; it cannot ensure that people have the time, access, knowledge, relationships or material conditions required to sustain it.

Sustainability debates often confront a similar puzzle. Governments increasingly understand the risks posed by climate change and many of the actions needed to address them, yet progress remains slow. The same gap was explored at a recent panel discussion, Managing Disruption: Climate Risk, Trust and the Future of Resilience. Although the discussion focused on climate risk, its speakers approached the difficulty of turning knowledge into action through three different lenses: government capacity, investment incentives and power. Their answers differed, but pointed to the need to connect knowledge, authority, finance and implementation.

Much of the panel's discussion framed this as a problem of coordination. But that raises a harder question: coordinated around what? Policy, finance, infrastructure and everyday practice may already reinforce one another very effectively – often in support of short-term returns, convenience, high consumption and established business models. Incentives help set that direction, while power influences whose interests it serves and how difficult it is to change. The challenge is therefore not simply to improve coordination, but to ask what existing systems are organised to produce, who benefits and what happens to practices that cannot compete on their terms.

The way governments are organised is part of the problem. Dr Harald Heubaum of the SOAS Centre for Sustainable Finance works with finance and planning ministries to integrate climate risk into routine decisions. Relevant knowledge frequently exists, he says, but "responsibility is spread across a number of different departments." A climate unit may understand the risks while control over budgets, planning and public investment sits elsewhere. Expertise, authority and resources are often separated and guided by different priorities.

Bridging that gap requires more than improved communication. A health department can promote the Mediterranean Diet, but its efforts will have limited effect if agricultural incentives, school procurement, retail policy and urban planning create a different food environment. Coordination means changing what institutions fund, permit and deliver, not simply improving the exchange of information.

Government fragmentation is only part of the explanation. Gosbert Chagula of Future Impact Ventures argued that fund structures, expected returns and investment horizons shape which solutions attract support. Julia Davies of We Have the Power added that some apparent failures of coordination persist because existing arrangements remain profitable for corporations with the power to resist change.

The same gap between responsibility and power appears throughout climate action. Households, farmers, communities and cities are asked to act, while much of the power over finance, infrastructure and regulation remains elsewhere. A farmer may be encouraged to rebuild soil while buyers, lenders and subsidies continue to reward short-term yields and low prices. The farmer carries the cost and risk of a transition whose wider benefits accrue to others.

The same division between responsibility and power is central to Roversi's account of the Mediterranean Diet. Families are held responsible for what they eat, while governments and companies exercise far greater influence over what is produced, priced, promoted and made available. As Roversi puts it: "Families are then blamed for choices made within systems designed to push the least healthy options."

The Mediterranean Diet remains scientifically credible and culturally celebrated, but it has not followed a single trajectory. The contrast between Pollica and places where it has lost ground shows that it has not simply disappeared. Its influence in everyday life depends partly on who can shape the food environment and what the wider system rewards. That uneven picture reveals a broader problem for sustainability: evidence alone does not determine what people can sustain in practice. The Mediterranean Diet leaves us with a harder question about change: who has the power to shape the conditions of everyday life, whose interests do those conditions serve, and how much influence do the people living with the consequences have over what comes next?

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