Healthy plant-based diet may prevent depression in young adults

University students on a healthy plant-based diet appear to have fewer depressive symptoms and a lower likelihood of developing mild-to-severe depression, suggests a study.

Some 392 students (mean age 20.9 years, 70.4 percent female) participated in the study. Mild-to-severe depression had a 36-percent prevalence. Higher healthy plant-based diet index (PDI) and overall PDI scores correlated with lower depressive symptom scores, while unhealthy PDI scores exhibited a positive but non-significant association after full adjustment.

Logistic regression analyses further showed the association between a healthy PDI and a lower likelihood of mild-to-severe depression (odds ratio, 0.51, 95 percent confidence interval, 0.28‒0.95; p_trend=0.030).

On the other hand, participants with greater adherence to unhealthy PDI were more likely to develop depression. However, this association was attenuated after adjusting for lifestyle-related variables.

“These findings highlight the importance of plant food quality, rather than plant-based diets per se, in relation to depression in young adults,” the investigators said.

This cross-sectional study conducted in 2023 used self-reported data from university students in Cuenca, Spain. The investigators calculated adherence to the overall PDI and to the healthy and unhealthy PDIs using data from a 137-item food frequency questionnaire.

Mild-to-severe depression was defined as Beck Depression Inventory II score >13 points. Adjustments for sociodemographic and lifestyle-related confounders were done in linear and logistic regression models.