VITAMIN D: Natures Anti-Depressant

     Vitamin D is a nutrient found in very few foods, added to others and available as a supplement. It is fat soluble meaning it is essential for your health and stored in your liver but does not need to be replaced everyday like water soluble vitamins. It is produced endogenously (from within) when skin is directly exposed to the sun, and most people meet at least some of their vitamin D needs this way. Skin exposed to sunshine indoors through a window will not produce vitamin D. Cloudy days, shade, and having dark-colored skin also cut down on the amount of vitamin D the skin makes. 

     Despite the importance of the sun to vitamin D synthesis, it is prudent to limit exposure of skin to sunlight in order to lower the risk for skin cancer. When out in the sun for more than a few minutes, wear protective clothing and apply sunscreen with an SPF (sun protection factor) of 15 or more. Tanning beds also cause the skin to make vitamin D, but pose increased risks for skin cancer. 

    Research has suggested the Vitamin D is a neuroactive steriod, a chemical that is targeted by certain SSRI (selective serotonin re-uptake inhibitor) antidepressants. A lack of Vitamin D can negatively affect the transport of Dopamine. This may explain the prevalence of depression in the winter, particularly in regions that receive less direct sunlight (Vancouver!!).

     Vitamin D is required for your body's use of calcium and phosphorous. It helps to form and maintain teeth and bones, and increases the amount of calcium that your small intestines absorbs. Vitamin D has other roles in the body including modulation of cell growth, neuromusclular and immune function, and reduction of inflammation. Muscles need it to move and the immune system needs it to fight off invading bacteria and viruses. Together with calcium it helps to protect older adults from osteoporosis. 

     Very few foods naturally have vitamin D. Fortified foods provide most of the vitamin D in North American diets.

• Fatty fish such as salmon, tuna and mackerel are among the best sources. 
• Beef liver, cheese, and some egg yolks provide small amounts. 
• Mushrooms provide some vitamin D. 
• Almost all North American milk supply is fortified with vitamin D but foods made from milk, like cheese and ice cream, are usually not fortified. 
• Vitamin D is added to many breakfast cereals and to some brands of orange juice, yogurt, margarine, and soy beverages; check the labels.