Diets may slightly reduce depressive symptoms in people with elevated cardiometabolic risk
While calorie-restrictive and low-fat diets may reduce symptoms of depression in those with high cardiometabolic risk, the certainty of the findings is low, according to a new systematic review and meta-analysis. There was insufficient evidence to assess the Mediterranean diet's effects.
Calorie-restriction and low-fat diets might reduce depressive symptoms among adults with elevated cardiometabolic risk, a meta-analysis found.
To evaluate the effects of dietary interventions on depression and anxiety, researchers conducted a systematic review and meta-analysis through December 2024, assessing randomized controlled trials (RCTs) that compared the effects on depression and/or anxiety of dietary advice with or without food provision versus no specific dietary advice or active interventions for three months or longer.
There were 25 RCTs with more than 57,000 adults. The diets included calorie restriction, low-fat, and Mediterranean. The primary outcome was change in depression and/or anxiety severity, and secondary outcomes included incidence of depression and anxiety and quality of life. The study was published by Annals of Internal Medicine on May 20.
Compared with no specific dietary advice, dietary advice on calorie restriction might have improved depressive symptoms in adults with elevated cardiometabolic risk (standardized mean difference [SMD], −0.23 [95% CI, −0.38 to −0.09]; low certainty), which would equal about a 2.4-point reduction on the Beck Depression Inventory scale (range, 0 to 63; minimum clinically important difference, 3.5). Low-fat diets also appeared to have very small effects on depressive symptoms in adults with elevated cardiometabolic risk (SMD, −0.03 [95% CI, −0.04 to −0.01]; low certainty), which would translate to a 0.31-point difference on the Beck Depression Inventory scale. Evidence on other diets, including the Mediterranean diet, and effects of diets on anxiety was limited.
The studies were primarily done in specific populations, such as those with increased cardiometabolic risk from age, metabolic syndrome, or menopausal status, and some populations had depression, anxiety, or another medical condition, such as malnutrition or cancer, at baseline. The authors also noted that the dietary interventions studied included a range of either face-to-face or group counseling and that studies often also supplied food to participants, which may not be feasible in the real world.
While calorie-restriction and low-fat diets might reduce depressive symptoms among adults with elevated cardiometabolic risk, the differences were small and confidence in the findings was low, the authors concluded. Limited evidence on other diets, comparisons of diets to active interventions, and other outcomes prompted the researchers to recommend further exploration in areas including the add-on effect of dietary intervention alongside first-line treatment for depression and/or anxiety.