This scoping review analyzed data from 42 randomized controlled trials and 23 systematic evidence syntheses. The studies looked at adults who followed anti-inflammatory dietary patterns, such as the Mediterranean or DASH diets, compared to control groups. The main goal was to see if these eating patterns could improve mental health outcomes like depression, anxiety, mood, stress, and quality of life.
The review found that 28 of the 42 trials reported significantly greater improvements in mental health for those on the diets. Improvements in depressive symptoms were the most consistent result across the studies. Systematic evidence syntheses also generally showed positive results for depression outcomes. However, the findings for anxiety were heterogeneous and less consistent, meaning results varied widely between different studies.
No serious adverse events or discontinuations were reported in the included studies, suggesting these diets were generally well-tolerated. The main reason to be careful is that the studies had high heterogeneity in how diets were defined, who participated, and how outcomes were measured. Readers should take from this that while the evidence points to potential benefits for depression, more research is needed to confirm these results and understand the underlying mechanisms before these diets can be recommended as a standard treatment.