Creating and supporting a healthy food environment for type 2 diabetes prevention
Authors: Buyun Liu, Yangbo Sun, Wei Bao
Journal: The Lancet Planetary Health (2018)

The widespread epidemic of type 2 diabetes mellitus in many countries1Zheng Y Ley SH Hu FB Global aetiology and epidemiology of type 2 diabetes mellitus and its complications.Nat Rev Endocrinol. 2018; 14: 88-98Crossref PubMed Scopus (2221) Google Scholar, 2Xu G Liu B Sun Y et al.Prevalence of diagnosed type 1 and type 2 diabetes among US adults in 2016 and 2017: population based study.BMJ. 2018; 362: k1497Crossref PubMed Scopus (244) Google Scholar renders the prevention of this condition a global priority for public health. Key modifiable risk factors for type 2 diabetes include obesity, an unhealthy diet, and a sedentary lifestyle. Individual-level interventions to promote a healthy diet and lifestyle have been proven to effectively reduce or delay the onset of type 2 diabetes.3Haw JS Galaviz KI Straus AN et al.Long-term sustainability of diabetes prevention approaches: a systematic review and meta-analysis of randomized clinical trials.JAMA Intern Med. 2017; 177: 1808-1817Crossref PubMed Scopus (169) Google Scholar Dietary and lifestyle choices are ultimately an individual matter and are determined by one's knowledge, attitude, beliefs, and skills. However, other factors at the family, community, and society levels could have profound effects, but these factors have not been thoroughly considered. Successful changes to promote healthy behaviours at an individual level might be best achieved with multi-level interventions that consider factors at interpersonal, organisational, community, and public policy levels (figure).4McLeroy KR Steckler A Bibeau D Glanz K The social ecology of health promotion interventions.Health Educ Q. 1988; 15: 351-377Crossref PubMed Scopus (4460) Google Scholar At a community level, evidence increasingly suggests an association between the local food environment and diabetes.5Mezuk B Li X Cederin K Rice K Sundquist J Sundquist K Beyond access: characteristics of the food environment and risk of diabetes.Am J Epidemiol. 2016; 183: 1129-1137Crossref PubMed Scopus (39) Google Scholar The neighbourhood food environment can affect the perceived availability of, access to, and exposure to foods and beverages. In their Article in The Lancet Planetary Health, Chinmoy Sarkar and colleagues6Sarkar C Webster C Gallacher J Are exposures to ready-to-eat food environments associated with type 2 diabetes? A cross-sectional study of 347 551 UK Biobank adult participants.Lancet Planet Health. 2018; 2: e438-e450Summary Full Text Full Text PDF PubMed Scopus (14) Google Scholar analysed large-scale cross-sectional data from 347 551 adult participants in the UK Biobank to examine the associations of exposure to ready-to-eat food environments (such as fast food takeaways, pubs and bars, and restaurants and cafeterias) with the odds of type 2 diabetes. The authors defined ready-to-eat food environments by use of a modelled and linked built environment database and objectively measured these environments within 1-km catchment areas of the residential streets of participants. Sarkar and colleagues found that the density of ready-to-eat food environments within a 1-km street catchment was associated with higher odds of type 2 diabetes. The associations were not appreciably changed after adjustment for potential confounders, including demographics, socioeconomic status, dietary and lifestyle factors, and body-mass index. This study benefited from use of a large and well characterised cohort that represented participants from 21 major cities of UK, which provided a high statistical power to detect the associations. Socioeconomic status is a potential confounder when assessing the association between a food environment and health outcomes. It has been assumed that people in areas that comprise many individuals of low socioeconomic status have less access to resources than their affluent neighbours. Such populated areas with poor access to nutritious and affordable food are often termed so-called food deserts. However, in the study by Sarkar and colleagues,6Sarkar C Webster C Gallacher J Are exposures to ready-to-eat food environments associated with type 2 diabetes? A cross-sectional study of 347 551 UK Biobank adult participants.Lancet Planet Health. 2018; 2: e438-e450Summary Full Text Full Text PDF PubMed Scopus (14) Google Scholar the associations persisted when several variables relevant to socioeconomic status (such as educational attainment, employment status, and income) were adjusted for, indicating that the association could not—or at least could not solely—be explained by socioeconomic disadvantage. Exposure to ready-to-eat food environments can increase the frequency of dining out and consuming ready-to-eat foods. Ready-to-eat foods are usually high in total fat or saturated fat and added sugar, which are associated with higher risk of type 2 diabetes.1Zheng Y Ley SH Hu FB Global aetiology and epidemiology of type 2 diabetes mellitus and its complications.Nat Rev Endocrinol. 2018; 14: 88-98Crossref PubMed Scopus (2221) Google Scholar In terms of cooking methods, frying is more commonly used in ready-to-eat food environments than at home. Another important but usually neglected food component when inferring the associations between food and health is unwanted contamination by environmental chemicals. People who dine out more often have increased exposure to obesogenic environmental chemicals, such as phthalates,7Varshavsky JR Morello-Frosch R Woodruff TJ Zota AR Dietary sources of cumulative phthalates exposure among the U.S. general population in NHANES 2005–2014.Environ Int. 2018; 115: 417-429Crossref PubMed Scopus (59) Google Scholar which are associated with an increased risk of type 2 diabetes.8Sun Q Cornelis MC Townsend MK et al.Association of urinary concentrations of bisphenol A and phthalate metabolites with risk of type 2 diabetes: a prospective investigation in the Nurses' Health Study (NHS) and NHSII cohorts.Environ Health Perspect. 2014; 122: 616-623Crossref PubMed Scopus (3) Google Scholar More research questions warrant further investigation. First, the population-attributable risk of type 2 diabetes that is associated with exposure to ready-to-eat food environments remains to be determined. The magnitude of the observed associations in the study by Sarkar and colleagues6Sarkar C Webster C Gallacher J Are exposures to ready-to-eat food environments associated with type 2 diabetes? A cross-sectional study of 347 551 UK Biobank adult participants.Lancet Planet Health. 2018; 2: e438-e450Summary Full Text Full Text PDF PubMed Scopus (14) Google Scholar was relatively small; for example, participants in the highest exposure categories to composite ready-to-eat outlets had 11% higher odds of type 2 diabetes than those with no exposure. However, given the large number of people living close to a ready-to-eat food environment, the population-wide health effects of exposure to these food environments would be substantial. Second, like other observational cross-sectional studies, the study by Sarkar and colleagues6Sarkar C Webster C Gallacher J Are exposures to ready-to-eat food environments associated with type 2 diabetes? A cross-sectional study of 347 551 UK Biobank adult participants.Lancet Planet Health. 2018; 2: e438-e450Summary Full Text Full Text PDF PubMed Scopus (14) Google Scholar could not infer temporality and causality of the association between proximity to a ready-to-eat food environment and the odds of type 2 diabetes. Carefully designed randomised controlled trials are needed to demonstrate the effects of modifying the local food environment, as a population-based approach, on the prevention of type 2 diabetes. Third, so-called unhealthy food environments also sell some healthy foods. The distribution of healthy and unhealthy food sources could change over time and vary by dynamic population characteristics. The association of changes in the local food environment with the risk of type 2 diabetes needs to be characterised. Finally, beyond access to various foods in a certain food environment, food prices, marketing, product advertising, perceptions of food quality and safety, and cultural habits can all serve a role in consumption behaviours. A major challenge to change food choices might be how to increase motivation to access healthier foods and the ability to do so. In summary, this large study by Sarkar and colleagues6Sarkar C Webster C Gallacher J Are exposures to ready-to-eat food environments associated with type 2 diabetes? A cross-sectional study of 347 551 UK Biobank adult participants.Lancet Planet Health. 2018; 2: e438-e450Summary Full Text Full Text PDF PubMed Scopus (14) Google Scholar shows the need for creating and supporting a healthy food environment in multi-level intervention efforts for prevention of type 2 diabetes. Understanding the effects of food environment on human health could provide the information and evidence necessary for top-down approaches, such as public policy and legal solutions, to improve the health and wellbeing of populations.9Lytle LA Measuring the food environment: state of the science.Am J Prev Med. 2009; 36: S134-S144Summary Full Text Full Text PDF PubMed Scopus (193) Google Scholar We declare no competing interests. Are exposures to ready-to-eat food environments associated with type 2 diabetes? A cross-sectional study of 347 551 UK Biobank adult participantsAccess to ready-to-eat food environments was positively associated with type 2 diabetes. Top-down policies aimed at minimising unhealthy food access could potentially reduce unhealthy consumption and risks of chronic diseases. Further long-term studies are needed to effectively guide such interventions. Full-Text PDF Open Access