Teenager im GlasA cross-sectional study appearing in Psychosomatic Medicine  (October 2010 72:763-768 Published online before print August 17, 2010); it looked at the dietary intake of B vitamins and its relationship to the incidence of depressive symptoms in 6,517 subjects between the ages of 12 and 15. Dietary intake was assessed by using a diet history questionnaire.  Subjects were determined to have depressive symptoms it they had a score greater than 16 on the Center for Epidemiologic Studies Depression Scale. The prevalence of depressive symptoms was 22.5% for boys and 31.2% for girls. Intake of dietary folic acid and vitamin B6 were both inversely associated with depressive symptoms. Riboflavin (B2) intake was inversely associated with depressive symptoms in girls, but not in boys. Increasing B vitamins in the diet may help reduce the prevalence of depressive symptoms in early adolescence.

In a double-blind, placebo-controlled study published in the Journal of the American College of Nutrition (1992;11(2):159- 163), B vitamins were given to geriatric patients suffering from depression. It was found that taking thiamin, riboflavin and pyridoxine (10 mg/day of each) created improvement in depression rating and cognitive function scores. The vitamins seemed to potentiate the antidepressant medication the subjects were taking. Interestingly, B12 levels increased in the treatment group, but not in the control group. B12 was not one of the supplements given.