Taking a daily vitamin D supplement could help give you an increased sense of well-being, improved sleep patterns and weight loss — all of which are linked to seasonal affective disorder.

- The Department of Medicine, Division of Geriatrics and Nutritional Science, Alzheimer’s Disease Research Center, Washington University School of Medicine in St. Louis released a study showing that depressed patients were 11 times more likely to have low levels of vitamin D. They also determined that low levels of vitamin D were associated with low mood and also not being able to complete certain mental tests.

- Other current research being done on vitamin D is showing that a deficiency may also play a role in 17 varieties of cancer (including breast, colon and prostrate cancer) as well as heart disease, and stroke.

- Vitamin D is also an anti-inflammatory hormone and good for treating irritable-bowel problems and arthritis. Studies are also showing that vitamin D is vital in the treatment of insulin resistance conditions such as diabetes.

- Vitamin D deficiency as an epidemic with Americans and Canadian especially during the winter months when sun exposure is low.