Placing restrictions on unhealthy food promotions is one way governments could help tackle the obesity crisis, but policymakers need to know what measures might be the most effective.

Obesity is a serious problem across the UK and Scotland has the highest prevalence of obesity and excess weight of any UK nation. Our diets are heavily influenced by our food environment – the availability and convenience of food, advertising prompts and the information that surrounds us. Our food environments shape our opportunity to be healthy – and our lives are saturated with unhealthy influences.

Obesity is a serious problem across the UK, and Scotland has the highest prevalence of obesity and excess weight of any UK nation. Our diets are heavily influenced by our food environment – the availability and convenience of food, advertising prompts and the information that surrounds us. Our food environments shape our opportunity to be healthy – and our lives are saturated with unhealthy influences.

Promotions on food and drink such as buy one get one free offers or discounts on price are disproportionately applied to unhealthy foods, meaning people tend to consume a higher number of unhealthy foods and drinks as a result of these offers.

In the UK, food and drink promotions are responsible for an 18% increase in the volumes of food we buy. And food and drinks higher in sugar are both more likely to be promoted and to be promoted for longer than products where sugar is naturally present.

Meaning that while promotions make food and drink products cheaper, they also encourage people to buy more unhealthy products.

That’s why Nesta and BIT are working with the Scottish government and the University of Oxford to test different methods of restricting the ‘promotion of value’ – the indication of a saving in price or increased volume for the same price – in food and drink promotions on high fat, salt and sugar product.

The project used a simulated online supermarket developed by the Health Behaviours team at the University of Oxford to test the effect of different deal promotions on the total calories purchased by shoppers.

Our goal was to understand the potential impact of restricting how discounts are communicated on purchasing high fat, salt and sugar foods. We hoped to use this information to help policymakers explore potential interventions and future legislation.

Our report discussed reasons why simulated environments might represent a promising setting to generate proof-of-concept evidence for some types of health interventions but might be less conducive to generate valuable evidence for others, such as those focussing on price. We found no significant difference between study conditions for total calories ordered in the hypothetical shopping task. Due to the uncertainty about the real-world applicability of the results, we caution against making policy recommendations solely based on this study.