Vitamin D Deficiency And Sad

As the warmer weather of summer months fade, some people find they are less energetic and more prone to mood swings as winter approaches. This decrease in vitality has led many to self-diagnose with seasonal affective disorder (SAD), a condition that, like vitamin D, is mediated by sunshine. However, whether or not SAD is directly related to vitamin D deficiency remains under speculation.

Vitamin D

Vitamin D is called the sunshine vitamin because of the way it is activated. Your body makes vitamin D in response to your skin's contact with sunlight. Once activated within the layers of your skin, vitamin D helps to maintain bone integrity by making your absorption of calcium more efficient. Other vitamin D functions include insulin regulation, reduction of inflammation and cell growth.

SAD

SAD is a spectrum condition characterized by depression, lethargy and increased appetite related to a change in the weather from sunny to dark. According to the Mayo Clinic, SAD usually starts in the fall as the sunshine of summer wanes. Since vitamin D relies on photoactivation in the skin, people that live in regions with little sunshine in winter tend to suffer from low levels of the vitamin during that time.

The Connection

Some research has shown chronically low levels of vitamin D can lead to depression. The inCHIANTI study, "Serum Vitamin D Levels and Depression in Older Adults," concluded vitamin D deficiency leads to depressive symptoms in adults over 65 years old. In another study, "Vitamin D vs broad spectrum phototherapy in the treatment of seasonal affective disorder," subjects who received vitamin D therapy experienced improved mood, while those receiving light therapy experienced little to none. Both studies state more research needs to be performed on a larger scale to verify the connection between mood and vitamin D.

Recommendations

According to the National Institute of Health's Dietary Supplement Fact Sheet, the recommended intake for vitamin D is 200 international units (IU) per day for adults between the ages of 19 and 50. Those recommendations increase to 400 IUs for adults between 51 and 70 years old, and 600 IUs for adults over 70. The most recent report from the National Health and Nutrition Examination Survey shows most Americans struggle to meet or exceed vitamin D intake.

Deficiency

If you are lactose-intolerant, over 65, have dark skin, live in colder climates or are vegetarian, you are more likely to be deficient in vitamin D. Over time, this deficiency can express itself in bone mineral density diseases such as rickets for children, and osteomalacia and osteopenia for adults. The National Institute of Heath's Dietary Supplement Fact Sheet does not list depression as an outcome for vitamin D deficiency.