Nutrition impacts depression in middle, older adulthood

Diet may increase likelihood of depression, especially in middle-aged and older women, according to new research published in the journal BMC Psychiatry.

The study was based on analysis of the Canadian Longitudinal Study on Aging data and included a sample of 27,162 men and women aged 45 to 85 years, of whom 4,739 were immigrants. 

The researchers found that lower intake of fruits and vegetables for both men and women, according to Karen Davison, PsyD, lead author of the study. Men were more likely to experience depression if they consumed higher levels of fat, or lower levels of omega-3 eggs. For all participants, lower grip strength and high nutritional risk were associated with depression, according to Davison.

The consumption of fruits and vegetables was protective against depression in our study, which has also been found in previous research. Anti-inflammatory and antioxidant components in fruits and vegetables may account for this relationship, Davison said.

Various minerals and vitamins, including magnesium, zinc, selenium, present in fruits and vegetables may reduce plasma concentrations of C-reactive protein, a marker of low-grade inflammation associated with depression. Depression was associated with having chronic pain and at least one chronic health condition for both men and women. For immigrant women, the study also found that the likelihood of depression is higher among those middle-aged and older when compared to Canadian-born women, the study found.

Researchers said the findings highlight the importance of health professionals being aware of the mind-body connection, with the hope that alleviating chronic pain may facilitate better mental health. In addition to nutritional intake, providers should consider influences earlier in life, including immigration status, education, and income, all of which may affect mental health.

"The study findings may help to define programs and policies that could help immigrants transition positively," said Davison. "In addition, this investigation helps to highlight the need to consider nutrition-related programming and policies relevant for all [people].”