Public health policy is increasingly shaped by what could be described as a “monoculture of nutrition”: a framework that treats food as the primary driver of obesity and cardiovascular risk while leaving other determinants largely unexplored, writes Professor Pietro Paganini.

Over the past decades, lifestyles have undergone a profound transformation. Free time has gradually become screen time. Spontaneous physical activity – walking, playing, exploring, standing up, and moving without thinking about it – once contributed significantly to daily energy balance. Today, that invisible component of movement has steadily declined, increasingly displaced by hours spent in front of smartphones, game consoles, and social media platforms.

Yet public debate continues to focus overwhelmingly on calories consumed and how food is made: what we eat, how much sugar we ingest, which nutrients should be limited, and how processed our food is, the now familiar but scientifically fragile and misleading category of Ultra-Processed Foods (UPFs). Policymakers have analysed, classified, and sometimes taxed caloric intake. But the human body is a thermodynamic system. Energy balance depends not only on calories in, but also on calories out. By focusing almost exclusively on intake, policy ignores the other half of the equation: energy expenditure. Movement, once an invisible but essential part of daily life, has progressively disappeared from modern lifestyles.

Scientific evidence increasingly links excessive screen time with reduced energy expenditure, sleep disruption, distracted eating, and worsening cardiometabolic markers. A person can be formally “active” for an hour a day and still be metabolically sedentary if the rest of the day is dominated by prolonged sitting and digital immobility.

The issue is not only the amount of time spent online. Digital platforms are not neutral environments. They are architectures designed to maximise attention and extend engagement. Infinite scrolling, push notifications, and intermittent rewards activate motivational mechanisms linked to dopamine and reward anticipation. The result is not merely entertainment but a restructuring of how we spend our time.

Among younger generations in particular, this combination – reduced movement, fragmented sleep, and continuous digital stimulation – can influence self-regulation and eating behaviours. The future of cardiovascular health will also be shaped in these environments.

Several countries are now considering bans on social media use for under-16s, largely driven by concerns about mental health and child safety. This growing awareness reflects an important point: digital environments shape behaviour. Yet this same logic is rarely applied when discussing obesity and cardiovascular prevention.

If policymakers believe it is legitimate to regulate food environments because they influence behaviour, then a question of coherence arises: why are digital environments, which reduce movement and disrupt sleep, largely absent from prevention strategies?

Taken to its logical extreme, the regulatory logic applied to nutrition could lead to a provocative conclusion. If we classify foods as “ultra-processed”, should we not begin to classify addictive scrolling as well? Let’s call it Ultra-Scrolling Social (USS).

It is a provocation. The point is not to create another questionable category like UPFs, nor to introduce new bans, taxes, or warning labels, neither on food nor on social media. In the field of nutrition, such instruments have produced insignificant results and significant unintended consequences. They are frequently regulatory shortcuts: easy to communicate, but poorly suited to addressing the deeper dynamics that shape everyday behaviour.

Prevention cannot be reduced to a moral classification of “good” and “bad”, whether foods or technologies. Reducing obesity and cardiovascular disease to a problem of individual products may be politically attractive, but it fails to capture the complexity of contemporary lifestyles.

Just as the food sector is encouraged to contribute to healthier diets through transparency and factual, science-based consumer information, digital platforms should also be part of the conversation. Greater transparency about algorithmic incentives, design features that facilitate breaks rather than compulsive use, and tools that support self-regulation – especially for younger users – could all play a role.

Health is not built through prohibition alone. It is built through balance. As long as policymakers continue to look only at the plate, they risk overlooking one of the most powerful environments shaping obesity rates and its causes today: the screen.

Professor Pietro Paganini is Adj. Prof. in Business Administration at the Fox School of Business, University of Philadelphia, and at John Cabot University. He is the chair of Competere, the EU policy institute.