Melissa Bess, former Nutrition and Health Education Specialist, Camden County, University of Missouri Extension
Vitamin D needs can be sufficiently met during the summer months thanks to the sun. Just 10-15 minutes of sunlight (without sunscreen) can provide us with 10,000 IU of vitamin D, which can be stored and used when needed. However, starting in November, the sun doesn’t get high enough in the sky in Missouri to provide us with the rays we need to absorb vitamin D in our skin. It may be necessary to take a vitamin D supplement in the winter months (November through February).
Vitamin D may be related to a wide range of health benefits, including an increase in immunity and muscle strength. It can also help with preventing osteoporosis, cancer, heart disease, diabetes, autoimmune disease (such as rheumatoid arthritis), depression and others. Research in these areas is still ongoing but shows some promising results.
The primary function of vitamin D is helping the body absorb calcium. Milk is one source of vitamin D, but not all other dairy products have vitamin D. Read the nutrition label to be sure. Other food sources of vitamin D are limited, but include fatty fish (salmon, sardines), eggs, some fortified cereals and breads, and some fortified beverages (soy milk and orange juice). Vitamin D will be listed with the other vitamins and minerals on the nutrition label.
The vitamin D recommendations were changed in 2010. Vitamin D is typically measured in IU or International Units. Infants up to age 1 need 400 IU daily; children (age 1 and up), adults (up to age 70), and women who are pregnant or breastfeeding need 600 IU daily. Adults age 71 and up need 800 IU daily.
Some experts recommend a vitamin D supplement of 1,000 to 2,000 IU because it is difficult to get the recommended amounts from food. Some may only need a supplement in the winter months because they may get enough sunlight in the spring, summer and early fall to get the vitamin D they need. Vitamin D can be stored, so the supplement doesn’t have to be taken every day. It is best taken with a calcium supplement or with dairy foods, to help with absorption of the calcium.
The tolerable upper level intake, the highest amount recommended, for vitamin D is 4,000 IU, but research has shown no toxicity in levels up to 10,000 IU. Toxicity would only occur from excessive supplement use, too much vitamin D from the sunlight will not occur.
Older adults, those with darker skin, those who always use sunscreen and obese individuals are at a higher risk for vitamin D deficiency because the body doesn’t synthesize the vitamin as well. These individuals may need to supplement at a higher level to get enough vitamin D.
Talk with your physician if you are interested in a vitamin D supplement. Some medications may interfere with a supplement and some may need to be taken at a different time.
To read more in detail about vitamin D, check out the Linus Pauling Institute’s webpage on vitamin D at http://lpi.oregonstate.edu/infocenter/vitamins/vitaminD/.
photo credit – Micolo J