Low levels of vitamin D have been linked to depression in the largest investigation of its kind.
Researchers at UT Southwestern Medical Centre confirmed that vitamin D has an effect on depression, particularly among those with a history of the condition, after smaller studies produced conflicting results.
Dr E Sherwood Brown, senior author of the study, commented: "Our findings suggest that screening for vitamin D levels in depressed patients – and perhaps screening for depression in people with low vitamin D levels – might be useful.
"But we don't have enough information yet to recommend going out and taking supplements."
Vitamin D is believed to affect neurotransmitters, inflammatory markers and other factors, which could help explain the relationship with depression.
Low levels of vitamin D are already associated with a myriad of health complaints, including cardiovascular disease and neurological complications.
However, excessive vitamin is thought to cause the onset of atrial fibrillation.
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