Researchers from the University of Assiut, Egypt conducted the first-ever double-blinded, randomized placebo-controlled clinical trial (RCT) to test the effectiveness and safety of vitamin D use in children with autism. Over a four month period, the two groups were exposed to either vitamin D (300 IU/kg/day) or an inert placebo. For comparison, US FDA recommend only 400 IU/day

The scientists reported significant improvements in autism symptoms and social maturity among the exposed group and no reported gains among the placebo group. Some of the improvements reported among the exposed children included reductions in irritability, hyperactivity, social withdrawal, and inappropriate speech.

A similar study, published in 2016, conducted by Dr. Richard Frye of Phoenix Children’s Hospital and colleagues, reported improvement in autism symptoms, particularly verbal skills, with supplementation of folinic acid.

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