Higher intakes of vitamin B9 may reduce depression

Higher blood levels of vitamin B9 (folate) may reduce the risk of depressive symptoms in men, says a new study.

In the study, vitamin B9 (folate) and homocysteine blood levels in 530 Japanese people were compared with depressive symptoms identified in over 36 percent of the male and female participants (1).

The results showed that depressive symptoms were less common in men with higher folate levels. Indeed, the highest levels were associated with a 50 percent reduction in the prevalence of depressive symptoms, compared to the lowest folate levels. On the other hand, a link between higher levels of the amino acid homocysteine and a higher prevalence of depressive symptoms in men was observed. In women, neither folate nor homocysteine was associated with depressive symptoms.

The research adds to a growing body of research linking folate and folic acid intake to improved mood, and follows a review of 11 studies involving 15,315 participants that reported low folate levels were linked to increased depression (2).

In 2003, U.S. researchers reported that folic acid supplements may help reduce the prevalence of depressive symptoms (3).

The World Health Organization (WHO) forecasts that within 20 years more people will be affected by depression than any other health problem; it ranks depression as the leading cause of disability worldwide, with around 120 million people affected.

1. Nanri A. et al. Serum folate and homocysteine and depressive symptoms among Japanese men and women. European Journal of Clinical Nutrition. January 2010.
2. Gilbody S. et al. Is low folate a risk factor for depression? A meta-analysis and exploration of heterogeneity. Journal of Epidemology and Community Health. 2007; 61(7): 631–637.
3. Morris M.S. et al. Depression and Folate Status in the US Population. Psychotherapy and Psychosomatics. 2003; 72(2):80–87.