In a recent study published in the journal Dialogues in Health, a group of researchers examined the impact of adherence to the EAT-Lancet diet during midlife on changes in body weight and waist circumference (WC) after a five-year period.
Study: Adherence to the EAT-Lancet diet in midlife and development in weight or waist circumference after five years in a Danish cohort. Image Credit: marilyn barbone / Shutterstock
Background
The global rise in obesity, a key risk factor for various non-communicable diseases like cardiovascular issues, cancers, and diabetes, highlights the urgent need for dietary shifts towards healthier, sustainable options. The EAT-Lancet diet, proposed by the Lancet Commission on Planetary Health in 2019, offers a blueprint for such a shift, aiming to balance human health and planetary sustainability. It recommends increased consumption of fruits, vegetables, plant proteins, and unsaturated fats while reducing red meat intake. Previous studies suggest vegetarian and similar diets may lower obesity risks. However, research on the EAT-Lancet diet's effectiveness for long-term weight management, particularly in Denmark, where national guidelines echo its principles, is scarce. Further research is needed to understand the broader implications of the EAT-Lancet diet on diverse populations and to explore its long-term effects on health and sustainability outcomes.
About the study
The Danish Diet, Cancer and Health Cohort (DCH) study explored the impact of dietary patterns on health among middle-aged Danes, with over 57,000 participants providing diet and lifestyle data. Researchers assessed adherence to the EAT-Lancet diet using a detailed food frequency questionnaire. Physical measurements at the study's onset included weight, WC, and height, with follow-up self-reported data collected five years later. These measures were validated to ensure accuracy, particularly the self-reported WC. Lifestyle factors, such as smoking status, physical activity, and medical history, were also recorded to adjust for potential confounders in the analysis.
Statistical methods were carefully chosen to analyze the data. Linear regression models explored the relationship between the EAT-Lancet diet adherence and changes in weight and WC, taking into account baseline measures and other lifestyle factors. The study also considered whether baseline weight and WC could act as mediators in this relationship, thus exploring both the direct and indirect effects of diet adherence on health outcomes. Furthermore, Poisson regression models were used to estimate the risk of obesity and elevated WC based on dietary adherence, with adjustments made for baseline characteristics and potential outliers in self-reported measures.
The study also accounted for the possibility of non-participation at the follow-up stage, using inverse probability weights to adjust for this bias. Sensitivity analyses further examined the robustness of findings, including the impact of developing significant health conditions during the study period.
Study results
In the present study, 44,296 participants from the initial 57,053 eligible individuals of the DCH were analyzed after excluding those with missing data. Notably, participants with higher adherence to the EAT-Lancet diet were predominantly female, non-smokers, more educated, consumed less alcohol, and had a history of hypertension, diabetes, and hypercholesterolemia. They also presented with lower weight, body mass index (BMI), and WC at the study's outset, despite the average WC exceeding recommended levels across all adherence groups.
The primary analysis revealed no significant weight change at follow-up among participants with the highest versus the lowest EAT-Lancet adherence scores, even after adjustments for energy intake. However, a different picture emerged for WC, with those in the highest adherence category showing a significantly lower WC at follow-up compared to those with the lowest adherence. This association persisted even after adjusting for energy intake.
When baseline weight and WC were not adjusted for, under the hypothesis that they might mediate the diet's impact, the highest adherence group showed significantly lower weight and WC at follow-up. This suggests the diet's potential direct and indirect effects on these outcomes. Additionally, analyses stratified by age, sex, baseline weight, and BMI revealed that the relationship between the EAT-Lancet score and weight or WC at follow-up differed mainly in groups stratified by BMI, indicating that baseline body composition might influence the diet's effectiveness.
For individuals with a baseline BMI under 30, those with the highest adherence to the EAT-Lancet diet had a significantly lower risk of developing obesity and elevated WC at follow-up, underscoring the diet's potential in obesity prevention. Sensitivity analyses, including adjustments for non-participation and excluding those who developed significant health conditions during the follow-up, supported the main findings, suggesting robust associations between diet adherence and health outcomes.
Conclusions
To summarize, the study found no significant relationship between the EAT-Lancet diet score and body weight after five years but identified a slight inverse association with WC. Higher adherence to the EAT-Lancet diet correlated with a reduced risk of developing obesity and elevated WC. This investigation contributes to understanding the EAT-Lancet diet's impact on weight management, suggesting potential benefits in WC reduction and obesity prevention, reinforcing the need for further long-term studies to explore the diet's effectiveness in broader populations.