In August 2019 researchers from Iran published their review of the medical scientific literature to assess the association between dietary Glycemic Index, glycemic load and depression. A total of 11 studies, involving 187,053 individuals, met the inclusion criteria and were included in the review. Six were cross-sectional studies, two cohort studies, and three clinical trials. Results showed that there was no significant association between dietary Glycemic Index and dietary glycaemic load with the risk of depression in the cross-sectional studies. However, the two cohort studies showed that a high dietary Glycemic Index was significantly associated with a higher risk of depression and the two clinical trials showed that there was a significant change in depression score after consumption of a high-glycemic load diet. The researchers therefore concluded that research findings were inconsistent and further research is required.
Salari-Moghaddam A et al. Glycemic index, glycemic load, and depression: a systematic review and meta-analysis. Eur J Clin Nutr. 2019 Mar;73(3):356-365.