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Lauren W.

Take a moment to roll your eyes at my corny attempt to title this article. Thank you.


Vitamin D is a star nutrient linked to numerous health benefits.

Studies suggest vitamin D may go beyond its well-established role in bone health and reduce the risk of cancer, heart disease, stroke, diabetes, autoimmune diseases, and more!


What makes vitamin D unique is that it is a vitamin and also a hormone your body can make from the sun. Despite the ability to get vitamin D from food and the sun, an estimated 40%-75% of people are deficient.

Why? Vitamin D is not abundant in our food choices and the sun is not a reliable source for everyone.


Many factors affect the skin's ability to produce vitamin D, including season, time of day, latitude, air pollution, cloud cover, sunscreen, body parts exposed, color, and age. Some dermatologists recommend using sunscreen and getting vitamin D from food and supplements rather than risk the harmful rays of the sun.


Role of Vitamin D

Vitamin D is needed for maximum absorption of calcium from the intestine, helping to build strong bones and teeth.

Together with calcium, vitamin D can help prevent osteoporosis in older adults. Without enough vitamin D, bones can become brittle and prone to fracture. It is estimated that more than 40 million adults in the U.S. have or are at risk of developing osteoporosis.

Vitamin D deficiency is associated with low bone mass and osteoporosis.


How Much Vitamin D Do You Need?

The recommendations for adults 69 and under are 600 IU/day, and 800 IU/day for adults starting at age 70. Older adults need more vitamin D because as they age, their skin does not produce vitamin D efficiently, they spend less time outdoors, and they tend to not get enough vitamin D.


Best Sources of Vitamin D

The sun is an excellent source of vitamin D, but it is hard to quantify how much vitamin D you get from time in the sun and the risk of skin cancer may outweigh the benefits. Supplements can fill in the gaps but it is always better to try to meet your nutritional needs with foods that contain fiber, phytonutrients, and more.

Unless you enjoy a diet that includes fatty fish or fish liver oils, it may be hard to get enough vitamin D naturally without eating fortified foods or taking a supplement. The major dietary source of vitamin D comes from fortified diary, along with some yogurts and cereals. Mushrooms, eggs, cheese, and beef liver contain small amounts.


Reading Food Labels

Daily Values are on nutrition fact panels to help consumers compare nutrients in products and to choose a healthy diet. The DV for vitamin D is currently set at 400 IU by the FDA, which is less than the recommended 600 IU.

Some advice: Do the math! When one serving says it meets 100% DV, you still need an additional 200 IU to satisfy your requirement.


How Much Is Too Much?

Vitamin D is a fat-soluble vitamin. Fat-soluble vitamins can build up in the body and are not as easily excreted as water-soluble vitamins. 4,000 IU is the 'tolerable upper limit' or the maximum amount that is safe to consume daily.


Acceptable Vitamin D Blood Levels

Your health care provider can check your vitamin D blood level with a simple blood test.

Using vitamin D blood levels is the best estimate of adequacy that accounts for dietary intake and sunshine, yet experts differ on what that level should be.