Low levels of vitamin D may lead to increased depression and other psychiatric problems in the elderly, it has been found.

Researchers from Amsterdam's Vrije Universiteit studied 1,282 people aged between 65 and 95, and found 26 suffered from major depression while 169 had minor depression - their vitamin D levels 14 percent lower than those unaffected.

The study further discovered poor vitamin D status led to an increase in hormones secreted by the parathyroid; overactive parathyroid glands being frequently linked with depression.

These findings could prove important in treating depression as low blood vitamin D levels and high parathyroid hormone levels can be corrected by dietary and calcium supplements or increased exposure to sunlight.