Where's the Vitamin D?

Vitamin D is an essential vitamin, helping to build strong bones and reducing the risk of osteoporosis. Here's advice on getting your daily dose of vitamin D.

Compared with most other vitamins, vitamin D is found naturally in only a few foods - specifically, fatty fish such as salmon, mackerel, sardines, and tuna. In addition, milk, some orange juices, and some breakfast cereals are fortified with vitamin D.

However, food is not the only way to get your vitamin D. You can take supplements containing the vitamin, and your skin can synthesize vitamin D from sunlight.

How Much Vitamin D Is Enough?
The National Academy of Sciences recommends that people age 50 and under consume at least 200 IU of vitamin D each day, those ages 51–70 consume 400 IU daily, and those age 70 and older, 600 IU a day.

The latest dietary guidelines recommend even more - 1,000 IU - for older individuals (whose bodies are not as efficient at absorbing vitamin D from foods or supplements or making vitamin D from sunlight), those with dark skin (who naturally make less vitamin D from sunlight), and those who live in northern climates or are housebound (and thus have minimal sun exposure throughout the year).

The Best Ways To Get Your Vitamin D
The best way to get vitamin D is to combine foods rich in this vitamin with a multivitamin or other vitamin D–containing supplement.

For example, you can easily meet the National Academy of Sciences’ vitamin D recommendation by having a bowl of vitamin–D fortified cereal with half a cup of vitamin D–fortified milk (90 IU) for breakfast, a glass of vitamin D-fortified orange juice (100 IU) or soymilk (120 IU) sometime during the day, and a multivitamin or vitamin D supplement (most contain 400 IU).

If you want to reach the higher dietary guidelines goal of 1,000 IU, take a second vitamin D supplement or eat fatty fish (200–360 IU) more often. Another option: Expose your face, arms, or legs to 10–15 minutes of sunlight without sunscreen two to three times a week. This is not the most efficient way to get your vitamin D, however. The skin’s ability to synthesize vitamin D decreases with age, and many people live in parts of the United States without year round sunshine.

Furthermore, the American Academy of Dermatology doesn’t advocate unprotected sun exposure as a means of getting adequate vitamin D, because of the risk of skin cancer - although it’s unlikely that you’ll get skin cancer from such brief periods of unprotected sun exposure, particularly if you alternate sites of exposure and apply sunscreen afterward.

Used with permission. Source: Johns Hopkins Health Alerts, posted in Nutrition and Weight Control, http://www.johnshopkinshealthalerts.com/alerts/nutrition_weight_control/, June 18, 2008.