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Cambridge Global Food Security

An Interdisciplinary Research Centre at the University of Cambridge
Junk Food

This very well attended online panel event, organised with Cambridge Public Health, took place on Monday 11th October, and focused on how and whether public policy should shape our diet. 

Professor Carol Brayne, chairing, started the event by reminding the audience that the subject has resonance beyond food; all public policy can be a political football, in both positive and negative ways.

Dr Dolly Theis explained that there have been 14 government strategies relating to healthy eating, and almost 700 policies over the last 30 years, but that little concrete action has resulted.

Professor Theresa Marteau began with a bold statement: yes, we can afford to scrap the policy… provided it is replaced by a more effective policy which could halve childhood obesity by 2030 and achieve net zero by 2050. If it isn’t replaced by such a policy, then the National Food Strategy published in 2020 is our best option.

She illustrated the difficulty faced by policy makers by explaining the common misperception that we, as individuals are in control of our own behaviour, and dietary choices, whereas in fact our behaviour is driven by cues in our environment.  For example, a study in which healthier snacks were placed nearer to the tills in shops resulted in markedly increased sales of healthier snacks to the study's participants, but when questioned, those involved had noticed no change in their habits.

Professor Giles Yeo explained that while genes play an important part in determining our body weight, it is the interaction of our genes and our environment which largely determines how obese we are likely to be.  There is no genetic difference between rich and poor, but those in the bottom socioeconomic quintile of society are twice as likely to be obese as those in the top quintile.  Making unhealthy foods cheaper will widen these inequalities.  Healthy food should be cheaper food.

Dr Theis pointed out that despite some recent administrations' good intentions, they haven’t remained in office long enough to see policies through. Changes in government, even if the same party is still in power, often result in the scrapping of policies and then the reinstatement of similar policies further down the line.

A lot of so-called ‘nanny state’ policies aren't about telling people what to do, as Dr Theis made clear; they're about shaping the environment to make it easier for people to make healthier choices

Professor Marteau added that negative ideas of the ‘nanny state’ are propounded by companies who spend billions of dollars lobbying government in order to keep adults and children smoking, consuming alcohol and eating junk food.

Professor Yeo agreed.  Rather than seeing the ‘nanny state’ as something that limits our freedom, we should recognise that the system we currently have is just as prescriptive; consumers are in effect being forced to make unhealthy choices, because of the lack of regulation in our food environment.

The event ended with a passionate endorsement of public engagement; while on a day-to-day level it may be difficult for the majority of the population to change their food choices, we can recognise that we want change and work with others to create a food environment that's healthier and more sustainable than the existing one, to make the healthier choice the easier, cheaper, more convenient choice.

Please find the event recording here.


Professor Carol Brayne, is Director of Cambridge Public Health, University of Cambridge where she is also Professor of Public Health Medicine. She was made a CBE in 2017 ‘for services to public health medicine’.


Professor Dame Theresa Marteau is Director of the Behaviour and Health Research Unit, University of Cambridge. She is a behavioural psychologist whose research focuses on changing behaviour to improve population health.

Professor Giles Yeo studies brain control of body-weight and is the author of Gene Eating, presenter of BBC2's Trust Me I'm a Doctor, and Professor of Molecular Neuroendocrinology at the MRC Metabolic Diseases Unit, University of Cambridge. He was made an MBE in 2020 for services to 'Research, Communication and Engagement'.

Dr Dolly Theis is a Research Associate at the MRC Epidemiology Unit, University of Cambridge. Her work is focused on what and who influences government obesity policymaking in England and previously on the link between child obesity and deprivation.

This event follows last year's Healthy eating: what makes it so hard?


Cambridge University Research News on Food Security