Ultra-processed foods have been linked to a range of health implications, but the level of consumption remains high. We spoke to researchers at Imperial College London to find out why.
The causes of overweight and obesity are often multifaceted and driven by both genetic and environmental factors. At a basic level, obesity and overweight result from an energy imbalance in the amount of calories consumed and expended. According to the World Health Organization (WHO), the rate of obesity has tripled worldwide since 1975, alongside an increase in the prevalence and consumption of micronutrient-poor and ultra-processed foods. Rising food prices and political inertia to promote healthier food options mean many families are reaching for the cheapest – and often least healthy – products, posing considerable implications for their long-term health. Children in particular are consuming high amounts of ultra-processed foods, leaving them at greater risk of maintaining unhealthy eating patterns when they reach adulthood. To discuss this further, Lorna Rothery spoke to Dr Kiara Chang and Dr Eszter Vamos from Imperial College London’s School of Public Health.
Can you outline the impact of obesity, and the secondary conditions associated with it, on the economy and health services in the UK?
Obesity is a global public health challenge and an important risk factor for type 2 diabetes, heart disease and some cancers. The UK has one of the highest rates of obesity, with one in three adults living with obesity and another third overweight. An estimated £6.1 million was spent on overweight and obesity by the UK’s National Health Service in 2014-2015, and the wider economic costs to society are estimated at £27 billion.
How far can the consumption of unhealthy and ultra-processed foods be linked to increasing levels of obesity across the UK? How do you expect the cost-of-living crisis will affect this?
Evidence from a randomised controlled trial shows that ultra-processed food consumption causes weight gain and excess calorie intake. Our previous research using large-scale and UK-based longitudinal data found a link between higher consumption of ultra-processed foods and increased risk of obesity and type 2 diabetes in adults and more rapid weight gain and body fat gain in children.
These foods are often relatively cheap, and during the cost-of-living crisis, many families struggle to access healthy foods with long-lasting effects on health. We need to make healthier foods more available and accessible for low-income households through subsidies and price promotions while taking action to restrict the marketing of ultra-processed foods.
Your research on ultra-processed food content of school meals and packed lunches in the UK noted that British children have the highest levels of ultra-processed food consumption in Europe. What are some of the key factors driving this?
The UK is a leading consumer of ultra-processed foods in Europe. British children consume, on average, 65% of their daily calorie intake from these foods; this is much higher than British adults, who consume 54% of their daily calorie intake from ultra-processed foods. There may be multiple factors contributing to this high level of consumption. Ultra-processed foods are typically designed to be hyper-palatable but have a low satiety potential and are more prone to over-consumption (we can eat a lot of them without feeling full). They are widely available and very convenient as they are ready to be consumed. Ultra-processed foods are also aggressively marketed with strong brands and especially target children (e.g., using cartoon characters on the packaging or advertising free toys). They are relatively cheap due to the use of low-cost ingredients in their production, and they are often marketed as healthy options.
In some of the world’s most developed economies, ultra-processed foods make up a significant proportion of people’s diets; do you think there is enough public understanding of the negative health impacts associated with their consumption? If not, why?
Consumption levels are highest in high-income countries but are rising most rapidly in low- and middle-income countries. Although public awareness has increased about the negative effects associated with their consumption, it is not always easy for consumers to recognise ultra-processed foods. Currently, the front-of-pack food labelling does not indicate how foods are processed. A practical way to identify them is to check if the list of ingredients includes food additives or anything that we do not usually use in home cooking (e.g., high-fructose corn syrup, hydrogenated oils, flavour enhancers, thickeners, etc.). These are often substances we are unfamiliar with and cannot even recognise as consumers. If at least one of these substances is included in the ingredients, it indicates that the product is ultra-processed.
The UK Government was criticised for delaying plans to ban pre-watershed TV advertising for junk food; what should be done at the policy level to promote healthier eating?
Aggressive advertising is a primary driver of the consumption of unhealthy foods, and the UK government’s decision to delay decisive actions to restrict junk food advertising is a missed opportunity. Since UK adults and children are leading consumers of ultra-processed foods globally, bold policy actions would be required to reduce their harmful health effects. For example, mandatory front-of-pack labelling on ultra-processed foods would assist consumers in selecting healthier food options. Fiscal policies that increase the price of ultra-processed foods and subsidise minimally processed foods and freshly prepared meals could promote the consumption of healthier and more nutritious foods. Updating public food procurement policies (government purchasing food or food services) could help prioritise locally sourced fresh foods and minimally processed foods while restricting the supply of ultra-processed foods.
Dr Kiara Chang
Dr Eszter Vamos
Clinical Senior Lecturer
Imperial College London
This article is from issue 25 of Health Europa Quarterly. Click here to get your free subscription today.