Vitamin D

Vitamin D is a nutrient needed to regulate calcium and phosphorous. The body produces vitamin D through a chemical reaction after 5 to 15 minutes of direct exposure to sunlight. People in northern locales and people who stay indoors are at risk for a vitamin D deficiency, which can lead to rickets and osteoporosis. Vitamin D also boosts the immune system and is known to prevent cancer and autoimmune diseases. Vitamin D is found in very few foods and supplements may be needed in certain cases to boost vitamin D levels. 

Try to supplement your vitamin D through food, if possible. A cup (237 ml) of fortified milk provides about 30 percent of your daily value. 3 oz. (85 g) of salmon or mackerel provides about 100 percent of the daily value. 3 oz. (85 g) of canned tuna provides about 40 percent. Eggs, liver and fortified cereals can provide about 10 percent of your daily value

Choose the correct vitamin D supplement. The most common kinds are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). D3 is recommended most often because it is the naturally occurring version of vitamin D in your body. For best absorption, take during a large meal.

Examine your medications. Certain medications interact with the absorption of vitamin D supplements and prevent healthy absorption. These medications include antacids, Lipitor, Dovonex, Lanoxin, Cardizem, Dilacor, Tiazac, Cytochrome P450 3A4 (CYP 3A4) substrates, Verapamil and water pills. Magnesium supplements also aren't needed while taking vitamin D, because the vitamin D increases magnesium levels.

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