Plant-Rich Diets May Help Prevent Depression
Eating a healthy diet, particularly a traditional Mediterranean diet, may help protect against depression, according to a systematic review and meta-analysis published online in Molecular Psychiatry.
Researchers assessed evidence from 41 studies, 20 of which were longitudinal. The studies looked at a handful of dietary approaches, including adherence to a traditional Mediterranean diet, the Healthy Eating Index, the Alternative Healthy Eating Index, the Dietary Approaches to Stop Hypertension (DASH) diet, and the Dietary Inflammatory Index.
Overall, evidence suggested anti-inflammatory foods rich in plant fiber, vitamins, minerals, and polyphenols—including fruits, vegetables, legumes, fish, olive oil, and nuts—may help decrease depression risk.
“There is compelling evidence to show that there is a relationship between the quality of your diet and your mental health. This relationship goes beyond the effect of diet on your body size or other aspects of health that can in turn affect your mood,” explained lead author, Camille Lassale, PhD, University College London, United Kingdom.
“We aggregated results from a large number of studies, and there is a clear pattern that following a healthier, plant-rich, anti-inflammatory diet can help in the prevention of depression.”
Four of the 41 studies analyzed, involving 36,556 adults, focused on the link between depression and a traditional Mediterranean diet. Participants with greater adherence to the diet, researchers found, had a 33% decreased risk of depression compared with participants who only adhered to a Mediterranean-type diet.
At the other end of the spectrum, eating a pro-inflammatory diet high in fat, sugar, and processed food was linked with higher depression risk, according to data from 5 longitudinal studies involving 32,908 adults.
“A pro-inflammatory diet can induce systemic inflammation, and this can directly increase the risk for depression,” said Dr. Lassale.
“There is also emerging evidence that shows that the relationship between the gut and brain plays a key role in mental health and that this axis is modulated by gastrointestinal bacteria, which can be modified by our diet.”
Lassale C, Batty GD, Baghdadli A, et al. Healthy dietary indices and risk of depressive outcomes: a systematic review and meta-analysis of observational studies. Molecular Psychiatry. 2018 September 26;[Epub ahead of print].