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below this natural homeostasis of vitamin D increase mortality. Overall, excess or deficiency in the calcipherol system appear to cause abnormal functioning and premature aging.
Mental health
Low levels of vitamin D has been associated with cognitive and behavioral effects; low levels of
vitamin D may affect general brain development and functioning and has been associated with seasonal affective disorder, Alzheimer's disease and schizophrenia. This link appears to be subtle and indirect. No causal association has been demonstrated, with much of the biological evidence coming from non-human experiments and only a small number of direct investigations involving humans.