In an effort to tackle the increasing prevalence of obesity, the UK government has introduced a number of public health strategies over the years, including changes to how we label foods. For example, the “traffic light” colour-coding system, which was introduced in 2013, aims to make it easier for consumers to know whether or not the foods they’re eating are healthy for them.
But some critics feel that this kind of labelling may still be difficult for people to fully understand or practically apply, and may not necessarily lead to people choosing healthier food. Given obesity is still on the rise, it’s clear current strategies aren’t working.
Recently, a team of researchers from Loughborough University proposed a different system of food labelling known as “physical activity calorie equivalent”, or Pace. This method illustrates how many minutes of exercise it would take to burn the calories in certain foods and drinks. The researchers showed that this new approach was easier for participants to understand – and may be more likely to help people avoid high-calorie foods.
But while these types of food labels have the benefit of being easier to understand, they could also run the risk of being misleading – and may not work for everyone.
Alongside being easier to understand, the team from Loughborough also showed in a previous review that using exercise to illustrate the equivalent calories in food and drinks can help people consume fewer calories – around 65 fewer calories every time they ate – compared with other food labelling methods.
Using exercise to illustrate the calories in food may therefore be a useful tool for consumers as it provides understandable, relatable information that may help them better plan their meals and workouts – potentially leading to healthier food choices while encouraging physical activity, both of which are key in reducing or preventing obesity.
While initial findings on exercise-based food labels seem promising, research is still needed in real-world settings and over longer periods of time if it’s going to inform future public health policy.
Another clear pitfall of the Pace approach is that it generalises calories burnt. This means that the averages used on labels may not actually be true of how each person burns calories.
A variety of factors – such as the type of exercise you’re doing, how intensely you’re exercising, your age and fitness level – all influence the amount of calories you burn. The way we digest and metabolise foods is also highly individual.
This could mean that general food labels could be deceptive. It’s unlikely that the calories estimated to be burnt on the packet will apply to everyone. This could lead to some people eating more or less food than they need.
Another reason the information on these labels could be misleading is that it makes the assumption that all calories consumed are equal. For example, two foods with the same calorie content may have different levels of fibre, fat, sugars or protein.
All of these are metabolised differently, which will influence how our foods are used and stored by our body. Low-fibre, high-sugar, energy-dense foods, for example, have been associated with weight gain compared with healthier options containing a similar number of calories.
Pace labels could also inadvertently encourage people to eat more poor-quality or ultra-processed foods as they may feel they can just exercise to burn those calories off. However, unhealthy, ultra-processed foods can still cause harm to the body, even if the calories in them are used.
Other experts feel that such types of food label will only have a short-term effect in changing food choices. Another concern is that Pace could trigger eating disorders or over-exercise in susceptible populations. It could also lead people to eat less so they can avoid doing the exercise required to burn off additional calories.
Labelling foods and drinks with the amount of exercise needed to burn them off may certainly have some benefits. However, it’s clear that a one-size-fits-all approach may be too simplistic when it comes to tackling obesity in a population. This is especially true when considering that every person’s diet, activity levels, lifestyle habits and even genetics are different from the next.
As such, strategies for reducing obesity should aim to take a more individualised approach to helping people increase their total daily movement and activity, while also helping them evaluate their eating patterns and portion sizes, as well as choosing better-quality foods.