Doctors reviewed eight multi-vitamin-mineral/mood studies covering 1,292 healthy men and women who took varying doses of multi-vitamin-minerals, or a placebo, for at least 28 days. Overall compared to placebo, those who took supplements were 65 percent less likely to perceive stress, 68 percent less likely to be anxious, and 70 percent less likely to report mild psychiatric symptoms. Fatigue and confusion were also 73 and 77 percent lower, respectively. Those who took supplements high in B vitamins reported the greatest mood benefits.

In discussing their findings, doctors said that the greater response to doses higher than the U.S. recommended daily allowances (RDAs) or dietary reference values (DRVs) suggests that RDAs and DRVs are inadequate to meet the needs of the brain, and also calls into question the assumption that diets with enough energy and protein also provide sufficient levels of micronutrients.

Reference: Psychosomatic Medicine; 2013, Vol. 75, 144-153