In a study of more than 81,000 women found those with the highest intake of vitamin D from food sources had a significantly lower prevalence of depressive symptoms.  (see PubMed article)

The researchers suggested that vitamin D may affect the function of dopamine and norepinephrine.

These are neurotransmitters that are likely involved in depression, while also modulating the relationship between depression and inflammation.

In another  paper published in the American Journal of Clinical Nutrition, Anthony Norman, an international expert on vitamin D, identifies vitamin D’s potential for contributions to good health in the adaptive and innate immune systems, the secretion and regulation of insulin by the pancreas, the heart and blood pressure regulation, muscle strength and brain activity.

Access to adequate amounts of vitamin D is also believed to be beneficial towards reducing the risk of cancer.

It has also been noted for its assistance in weight loss and general nutrition.

More information about Vitamin D in preventing depression can be found in a study on the website Green Med Info:

“… [A]n increasing number of clinical studies have shown that treating gastrointestinal inflammations with probiotics, vitamin B, D and omega 3 fatty acids, through attenuating proinflammatory stimuli to brain, may also improve depression symptoms and quality of life. All these findings justify an assumption that treating gastrointestinal inflammations may improve the efficacy of the currently used treatment modalities of depression and related diseases.”
This adds to growing evidence showing that if you’re suffering from depression one of the best choices you can make is to spend as much time outdoors in the sun as possible.

Sun exposure is by far the best way to optimize your levels of vitamin D.