Research Suggests Vitamin D Regulates Enzyme That Converts Tryptophan Into Serotonin.

A growing body of evidence suggests that vitamin D — present in some foods and produced naturally when skin is exposed to sunlight — regulates the enzyme that converts the amino acid tryptophan into serotonin, a neurotransmitter believed to help regulate moods and direct brain development while in the womb. http://www.bostonglobe.com/lifestyle/health-wellness/2015/01/05/research-suggests-vitamin-could-affect-brain-function/kdJThHsLlEpVRrdaesCS0K/story.html