Coronavirus has laid bare the need for countries to lose weight. Britain is no exception, with 63% of adults in the nation being overweight or obese – comprising a high-risk group which has been disproportionately affected by COVID-19.
To tackle this issue, the UK government’s latest plan to make the country fitter involves a raft of new measures, one of which is to make calorie labelling on menus compulsory. The underlying reasoning is seemingly straightforward: caloric information will allow people to make more informed, and possibly healthy, choices when ordering at restaurants. But in practice? Research shows it’s not so simple.
Proponents of menu labelling have long been adamant that doing so encourages weight loss. In 2009, when a similar law was enforced in California, the Los Angeles County’s Public Health Department made a gallant prediction that it could cut down on up to 40% of annual weight gain.
But data to support the assumption that people will make more mindful food choices when presented with caloric information is shaky at best. A study conducted in New York, where menu labelling became mandatory in 2008, showed that whilst customers were conscious of the information at first, people gradually became desensitised to the labels and started ignoring them over time.
Another review published in 2017 found that menu labelling lowered calorie consumption only in a few select settings, such as cafeterias, but not, more crucially, at fast-food eateries. Both studies came to the same conclusion – that there was little evidence to show that calorie labelling could significantly change people’s behaviour.
Whether or not calorie labelling spurs health consciousness is still up for question, but its overall impact on food habits among the public may very well be adverse. Caloric information on menus are immense triggers for those struggling or recovering from eating disorders, for whom calorie counting is an obsessive compulsion, used to control and limit food intake to dangerous extremes.
Findings published in a study by the Journal of the Academy of Nutrition and Dietetics revealed that those most likely to change their eating habits and choices when presented with labelled menus were people with histories of disordered eating, like taking laxatives, skipping meals, and purging. So it seems that while menu labelling will do little to dissuade most people from overeating, it may encourage those on restrictive diets to under-eat and starve themselves, facilitating and exacerbating the growing prevalence of eating disorders.
Indeed, there is an argument to be made that incentives produced by calorie labelling are two-fold: regardless of consumer behaviour, mandatory menu labels create pressure for restaurants to offer more low-calorie options. But all this shies away from the fact that calorie labelling is in and of itself unreliable, as an indicator of how much energy will be in your food.
Unlike packaged and processed food – where production is mostly automated – the calorie content of your restaurant order depends on serving size and portions of different ingredients, which can fluctuate widely with the individual cook, and sheer human randomness. This was brought to attention when a team of researchers purchased food from various restaurants and calculated their calorie content in the lab, finding that 20% of orders contained at least 100 more calories than reported on the menu label.
And not only are calorie counts inaccurate as general data, but they also fail as legitimate arbiters of nutritional value – which is arguably more important when it comes to maintaining healthy body weight. At the most basic level, calories are a scientific measure of energy: the logic being that the difference between calorie intake and calories burned will determine whether and how much you gain or lose weight. But whilst this may be true as a broad guideline, the age-old mantra that ‘a calorie is a calorie is a calorie’ simply doesn’t hold up when examining the biochemistry.
Scientists have shown time and time again that how a calorie is processed varies widely with the individual’s genetics, lifestyle habits, and also the type of nutrient that the calorie comes from – resulting in vastly different implications for energy intake and weight loss.
Factors such as the speed of digestion and the thermic effect (how much heat is lost during metabolization) affect how satiated you feel, thus how likely you are to eat more, and how much energy is absorbed by the body.
For instance, while simple sugars are rapidly broken down to produce a steep spike in blood glucose, complex carbohydrates lead to a steadier rise in sugar levels, helping you feel full for longer. When proteins are digested, 25–30% of energy is lost as heat, compared to 2-3% for fats; to put this into perspective, your body may absorb 98 calories from 100 calories of fat but only 70-75 from an identical amount of protein. Considering the bigger picture, then, it’s clear that calories aren’t as relevant in the equation for weight loss as we would like them to be.
It’s not rocket science that a salad will be better for you than a diet coke – even when the latter clocks in at zero calories. If the goal is to make tangible and long-lasting steps towards becoming healthier as a society, then increasing education in healthy nutrition and eating is a good place to start: precisely to dismantle outdated and pernicious myths about calorie counting and dieting.
There’s no denying that obesity and overeating is a huge issue; but insofar as changing people’s habits for the better, slapping a few numbers on the side of a menu won’t quite do the trick – policymakers will have to step up their game against complex and ingrained lifelong behaviours.