Did Mandatory Calorie Labels Help Improve Health in the UK?

In April 2022, mandatory kilocalorie (kcal) labelling in the out-of-home food sector was introduced as a policy to reduce obesity in England. Large out-of-home food sector outlets subject to kcal labelling legislation were visited pre- and post-implementation, and customer exit surveys were conducted with 6,578 customers from 330 outlets. Kcals purchased and consumed, knowledge of purchased kcals and reported noticing and use of kcal labelling were examined. The results suggested that the introduction of the mandatory kcal labelling policy in England was not associated with a significant decrease in self-reported kcals purchased.

Food provided in the OHFS tends to be energy-dense and high in kilocalories (kcals). Frequently consuming food from the OHFS is associated with increased obesity risk. This is problematic because, according to a 2015 study, 27% of UK adults eat foods in the OHFS once per week or more. Obesity is a major global public health problem. In England, recent data suggest that 26% of people live with obesity, with obesity linked to a range of diseases, including type 2 diabetes, several cancers and cardiovascular disease. Obesity produces a substantial healthcare burden in the United Kingdom. A likely contributing factor to obesity is the out-of-home food sector (OHFS). Obesity is also socio-demographically patterned, and public health interventions are required to reduce obesity and its social inequalities.

Multiple countries, including the United States and parts of Canada have implemented mandatory kcal labelling legislation in response to the growing contribution of the OHFS on diet. In 2011, as part of the UK public health responsibility deal, OHFS businesses were encouraged to make voluntary pledges to provide kcal labelling. However, a 2018 study found that only 17% (18 out of 104) of OHFS outlets assessed in England were providing in-store kcal labelling, and when labelling was present, it did not adhere to government-proposed best practice guidelines. Motivated by a lack of voluntary compliance, the UK government announced the Calorie Labelling (Out of Home Sector) Legislation 2021, with a policy enactment deadline of 6 April 2022 for eligible businesses. The legislation applied to large (>250 employees) businesses (cafes, fast-food outlets, sit-down restaurants and pubs) in England selling food for immediate consumption. It requires businesses to provide kcal labelling on all unpackaged food and non-alcoholic drink items that are on the menu for more than 30 days per year, alongside contextual information on recommended kcal consumption.

Systematic reviews examining the effect of kcal labelling on consumer behaviour have concluded that kcal labelling has a modest to null effect on kcals selected or purchased. For example, a Cochrane review by Crockett et al. indicated that kcal labelling was associated with a reduction of ~47 kcals purchased, but there was a high level of uncertainty in this estimate. Similar to England, the United States implemented mandatory labelling applying to food outlets with more than 20 locations in 2018. Petimar et al. examined whether kcal labelling changed purchasing behaviour for meals across 104 restaurants from a fast-food franchise pre- versus post-policy implementation. Using retail transactions, they demonstrated that kcal labelling implementation was associated with a reduction of 54 kcals per transaction.

Kcal labelling in the OHFS could lead to a reduction in kcal consumption by influencing individuals’ food choices and through menu reformulation. In addition, changes in consumer behaviour following the implementation of kcal labelling may be mediated by the level of existing knowledge of the kcal content of menu items in the general population, which may explain varying associations and impacts of kcal labelling in different populations and settings.

For example, kcal labelling may have a greater impact on food choices if knowledge of kcal content of OHFS foods is poorer and could also have differing effects depending on whether menu items’ energy content tends to be under- or overestimated. Moreover, it may be the case that people somewhat randomly underestimate or overestimate the number of kcals in food items. For example, people may underestimate for the least healthy foods but overestimate for the healthiest foods or vice versa. If this is the case, the impact of kcal labelling could be influenced by the consumers’ original assumption of the number of kcals in the food item. Depending on this assumption, kcal labelling may lead to fewer or more kcals purchased by consumers.

So far, there has been no examination of whether the introduction of mandatory kcal labelling in England was associated with a reduction in the amount of energy purchased or consumed from the OHFS. Understanding whether the effects of the introduction of mandatory kcal labelling in the OHFS may differ by population socio-demographics will also be critical to understanding its potential to narrow or widen health inequalities.

This study examined energy purchased and consumed by customers in the OHFS pre- versus post-implementation of mandatory kcal labelling legislation in England. This study also examined whether customer estimation of energy content of their purchases, self-reported noticing and the use of kcal information differed pre- versus post-policy implementation.

The current study did not observe an association between kcals purchased or consumed in OHFS pre-implementation (2021) versus post-implementation (2022) of mandatory kcal labelling legislation in England (adjusted models). Additional analyses indicated that the lack of observed change did not differ on the basis of participant age, gender, ethnicity or SEP (education level). Reported noticing of kcal labelling post-implementation significantly increased, and customers more accurately estimated the kcal content of their purchases at post- versus pre-implementation. Despite this, there was only a small change in reported use of kcal labelling pre- versus post-implementation (77/3,308 pre-implementation and 209/3,270 post-implementation).

Strengths and weaknesses of the study

This study examined purchasing, consumption and noticing and use of kcal labelling in the OHFS in England before versus after implementation of the national mandatory kcal labelling policy. This study recruited a large number of participants from a range of food outlets across multiple local authorities and area-level deprivation quintiles. Local authorities were purposively sampled to be generalisable across other areas of England and included outlets representing a large number of national chains.

A limitation of this study is the reliance on self-reporting of food purchased and consumed, which may introduce bias. To mitigate inaccurate reporting, food purchases were recorded shortly after consumption and, where possible, customer receipts were used to verify purchases, although this was not always possible due to not being consistently issued by outlets. The calculation of kcals purchased was based on businesses’ reported kcal information for menu items.

Previous research has indicated that this tends to be accurate but may be prone to underestimation of the energy content of some food items; for example, one study found that kcal counts on menus were generally accurate, but restaurants underreported compared with fast food outlets. We are not aware of any evidence suggesting that the accuracy of kcal information has changed over time, and so we presume this limitation is unlikely to introduce bias to the present results in relation to change estimates; however, kcal purchasing and consumption may be underestimated in this study. The use of objective verified measures of energy purchased and consumed would be preferable but was not feasible in this real-world policy evaluation. Further, it may be the case that people who were approached to take part in the study and declined may have purchased and consumed meals with a higher or lower energy content than participants sampled. Due to this, the data presented could be an underestimation or overestimation of the number of kcals purchased and consumed by people in the OHFS. However, there are no a priori reasons to expect this variance to be systematically different between pre- and post-policy implementation and, thus, not introducing substantial bias.

Although their study can conclude that the implementation of the policy was not associated with an immediate change in energy purchased and consumed, we cannot infer causality from a pre–post design owing to the inability to fully adjust for known and unknown confounders or compare data with any background trends (for example, pre-implementation data were collected shortly after coronavirus disease 2019 restrictions were removed in England).

Previous research has examined consumer behaviour changes following the implementation of kcal labelling in the OHFS; however, this has predominately been done in North America. A small number of US studies have suggested that the introduction of kcal labelling was associated with small decreases in energy purchased in two fast food franchises and a supermarket chain selling prepared food, but there has been no national evaluation of the US kcal labelling policy.

In the United Kingdom, a limited number of trials in real-world settings have found no evidence that the introduction of kcal labelling reduced overall energy purchased. Systematic reviews have produced similar findings, concluding that the quality of evidence is low and that kcal labelling has a small or no effect on the amount of energy selected, purchased and/or consumed. The lack of an observed association between mandatory kcal labelling and energy purchased and consumed in the present study is not consistent with the three US studies described above. However, these examined single fast food and supermarket chains (selling prepared food) in the United States, rather than the broad range of eligible OHFS businesses in the present study. In addition, contextual differences between the United States and England may also explain different findings, such as socio-demographic patterning, frequency of OHFS visits and/or food choice motives.

Research has shown that a notable proportion of individuals do not notice kcal labels when eating out. Larson et al. found that, out of 1,830 US adults, only 52.7% were aware of kcal labelling when eating at a restaurant in the past month, with 38.2%, among those who noticed labelling reporting that they did not use it when making their purchase decision. In their study, only around 30% of people post-implementation reported noticing kcal labelling. Of those people, only 22% (209/3,270) across all participants post-implementation) reported that they used this information when making their purchasing decisions.

Despite a small increase (3%) in reported usage post-implementation, this may explain the lack of an association with consumer purchasing found in this study. Although there was an increase in participants who reported noticing kcal food labelling following mandatory implementation (an increase from 17% to 32%), these figures are still relatively low compared with figures from the United States (for example, 60% noticed kcal labelling). Labelling guidance is similar between the United States and England. However, a US study examining compliance found that 94% of 197 chains had implemented kcal labelling post-regulations, which is higher than compliance rates found in England (80%). This greater level of compliance may have contributed to higher reported noticing and use of kcal labels in the United States and may have contributed to lower levels of reported noticing and use of kcal labels in this study. The lower compliance rates found in England has potentially limited the effectiveness and impact of the policy on customer noticing and use of kcal labels and, in turn, probably impacts on kcals purchased and consumed.