Greater adherence to EAT-Lancet diet linked to lower depression and anxiety risk

By Pooja Toshniwal PahariaReviewed by Danielle Ellis, B.Sc.Jul 8 2024

In a recent study published in Nature Communications, researchers determined the association between EAT-lancet dietary adherence and incident anxiety and depression.

In the present study, researchers investigated whether adhering to the EAT-Lancet diet could lower anxiety and depression incidence among 180,446 United Kingdom Biobank participants.

About the study

The study included UK Biobank members who have completed an online 24-hour food recall questionnaire at least once. Exclusion criteria included withdrawal, anxiety or depression, anxiolytic usage, and abnormal total energy intakes (below 500 or more than 3,500 kcal/day in females, below 800 or more than 4,000 kcal/day in males).

The researchers utilized the Oxford WebQ to obtain dietary data from the remaining 70,000 individuals, who completed four more online questionnaires at 3–4 monthly intervals between February 2011 and April 2012, based on a 24-hour food recall from the preceding day. They used the EAT-Lancet diet index to assess adherence to the EAT-Lancet Commission's recommendations for healthy diets derived from sustainable food systems. They used three diet scores, i.e., the Knuppel index, the Kesse-Guyot index, and the Stubbendorff index, to analyze the link between EAT-Lancet diet adherence and anxiety and depression.

The researchers tracked the subjects from baseline until outcome occurrence, death, or the last follow-up date (March 23, 2021), whichever came first. They determined illness outcomes using self-reported medical problems, primary care, hospital data, and death registry information. They used the International Classification of Diseases, tenth revision (ICD-10) codes to identify anxiety and depression.

The researchers used Cox proportional hazard regressions to calculate the hazard ratios (HR) for the analysis. Study covariates included age, gender, body mass index (BMI), ethnicity, total calorie intake, alcohol use, smoking status, physical activity, Townsend deprivation index, and hypertension. The researchers used limited cubic splines to assess dose-response correlations.

The planetary health EAT-Lancet diet index was compared to other diet scores for incident mental illnesses using a net reclassification improvement (NRI) index. They performed sensitivity analyses, eliminating people who completed the online dietary recall questionnaire just once, repeating the analysis with the most recent diet assessment, and omitting depression, anxiety, or co-occurring cases within the first five years of follow-up.

They investigated potential links between dietary adherence and mental diseases by testing relationships between various components of the EAT-Lancet index and outcomes and conducted mediation studies.

Results

The study comprised 180,446 individuals; the mean participant age was 56 years, and 47% (n=83,824) were male. During a 12-year median follow-up, the researchers recorded 6,026, 4,548, and 1,262 incidents of anxiety, depression, and their concomitant occurrence, respectively. The median values for the Knuppel, Stubbendorff, and Kesse-Guyot indexes were 11, 22, and 44, respectively.

Participants in the maximum adherence group for the Knuppel index had reduced odds of anxiety (HR, 0.8), depression (HR, 0.8), and their simultaneous occurrence (HR, 0.8) than the lowest adherence group. The corresponding HR values for the Stubbendorff index obtained were 0.7, 0.8, and 0.7, respectively, while the Kesse-Guyot index was 0.8, 0.8, and 0.8. Each extra point on the EAT-Lancet dietary score reduced the probability of depression, anxiety, and their combined incidence by 5.1% (HR, 0.95), 4.7% (HR, 0.95), and 6.3% (HR, 0.94), respectively. Restricted cubic splines revealed a linear relationship between each dietary indicator and the risk of anxiety and depression.

Kesse-Guyot and Stubbendorff indices enhanced risk categorization for anxiety, depression, and their concomitant occurrence. The Knuppel index enhanced risk categorization for new-onset depression, with an NRI of 0.04. Indices for the Mediterranean diet, the Dietary Approaches to Stop Hypertension (DASH), and unhealthful plant-based diets improved risk categorization for new-onset anxiety, depression, and concomitant occurrence, with NRI values of 0.08, 0.04, and 0.11, respectively.

Higher adherence to vegetable guidelines decreased the incidence of anxiety and depression. BMI mediated the correlations of the Knuppel index scores with anxiety, depression, and their simultaneous by 22%, 7.8%, and 19% of the correlations, respectively. Adherence to the planetary health EAT-Lancet diet index was more prominent among the impoverished.

Conclusion

The study found that the EAT-Lancet dietary pattern might lower the risk of anxiety and depression. Adherence to vegetable and fruit guidelines significantly reduced anxiety and depression risk. Higher fish intake was likewise inversely related to all mental outcomes. The findings imply that the EAT-Lancet diet can benefit physical and mental health, perhaps reducing risk disparities between socioeconomic groups and decreasing anxiety and depression.