I will second vitamin D3, the majority of the population has sub-optimal intake of this critical vitamin. Among other things, the active metabolite of vitamin D3, calcitriol, is a glutathione modulator, and possibly a catalyst! The vitamin D supplied in fortified foods is vitamin D1 (strong bones), this is not the same as the other forms of vitamin D; D1 and D3 are not interchangeable. I recommend 2,500 I.U. daily for all adults, and 4000 I.U. daily for pregnant women; I feel this stuff is as important for fetal brain development as folic acid. D3 protects the fetal brain from excitotoxicity from reactive foreign invaders, i.g. rhinoviruses (i.e. the common cold). This is why winter births and black skin are correlated with schizophrenia and mental illness, the mother get infected with the flu, and being deficient in D3 (low glutathione), the virus is able to attack the developing child's brain.