Researchers at Rush University Medical Center in Chicago found that for every 10 milligram increase in the vitamin B6 intake and for every 10 microgram increase in vitamin B12 there was a 2 percent per year decrease in the risk of developing depression symptoms. 


Previous studies have associated a lower risk of infection to vitamin B intake.  Within the next 2 decades, according to the World Health Organization, more persons will be affected by depression than any other health condition.  It also considers depression as the worldwide leading cause of disability affecting approximately 120 million people.


The study obtained data from over 2500 people over 65 years of age living in the Chicago area.  The volunteers were living in a community.  Dies were measured using food frequency questionnaires and depressive symptoms were assessed using the Center for Epidemiologic Studies’ Depression.


During 7 years of follow-up, researchers found that the increased intakes of vitamins B12 and B6 are associated with a “decreased likelihood of depression.”  The intakes of the vitamins were from food and supplements.


However, the benefits were limited to supplement consumption, according to Kimberly Skarupski, the lead researcher. 


No link between depressive symptoms and food intakes of B12 or B6 were observed. This may be due to the fact that the food supply quantity of these vitamins is assumed but not confirmed.


“Our results support the hypotheses that high total intakes of vitamins B6 and B12 are protective of depressive symptoms over time in community residents.


There is a biologically plausible relationship between vitamin B intake and depression, according to a study conducted in Finland in 2003.  The researchers of that study in t BMC Psychiatry noted that vitamin B12 is involved in the production of neurotransmitters, and some  are linked to mood function (and dysfunction).


Also, vitamin B12 may stop the accumulation of the toxic amino acid homocysteine, which may lead to chemical reactions that enhance depression.  Other studies have found that over 50  percent of people with depression have elevated homocysteine levels.



American Journal of Clinical Nutrition