While you’re catching some rays this summer, think about vitamin D. Sometimes called the “sunshine vitamin” because it’s produced in your skin in response to sunlight. Vitamin D is a fat-soluble vitamin in a family of compounds that includes vitamins D1, D2, and D3. It can affect as many as 2,000 genes in the body.
Learn about everything vitamin D has to offer.
Vitamin D has several important functions. Perhaps the most vital are regulating the absorption of calcium and phosphorous, and facilitating normal immune system function. Getting a sufficient amount of the vitamin is important for normal growth and development of bones and teeth, as well as improved resistance against certain diseases.
In addition to its primary benefits, research suggests that vitamin D may also play a role in:
- reducing your risk of multiple sclerosis, according to a 2006 study published in the Journal of the American Medical Association
- decreasing your chance of developing heart disease, according to 2008 findings published in Circulation
- helping to reduce your likelihood of developing the flu, according to 2010 research published in the American Journal of Clinical Nutrition
Your body produces vitamin D naturally through direct exposure to sunlight. A little can go a long way: just 10 minutes a day of mid-day sun exposure is plenty, especially if you’re fair-skinned.
Besides getting vitamin D through sunlight, you can also get it through certain foods and supplements. The National Institutes of Health (NIH) recommends that you obtain vitamin D from all three of these sources in order to ensure adequate levels of the vitamin in your blood.
Many lifestyle and environmental factors can affect your ability to get sufficient amounts of this vitamin through the sun alone. These factors include:
- use of sunscreen
- spending more time indoors
- working longer hours in offices
- living in big cities where buildings block sunlight
These factors contribute to vitamin D deficiency in an increasing number of people. That’s why it’s important to get some of your vitamin D from sources besides sunlight.
Although few foods contain vitamin D naturally, some foods are fortified with it, which means that the vitamin is added to the food. Foods that contain vitamin D include:
- egg yolk
- milk (fortified)
- cereal (fortified)
- yogurt (fortified)
- orange juice (fortified)
It can be hard to get enough vitamin D each day through sun exposure and food alone, so taking vitamin D supplements can help.
There has been some controversy over the amount of vitamin D needed for healthy functioning. Recent research indicates that we need more vitamin D than was once thought.
The Institute of Food and Agricultural Sciences (IFAS) reports new intake recommendations (based on international units—IUs—per day):
- children and teens: 600 IU
- adults up to age 70: 600 IU
- adults over age 70: 800 IU
- pregnant or breastfeeding women: 600 IU
Some sources suggest that considerably higher daily amounts of vitamin D—as high as 2000 IU per day—are needed. The NIH emphasizes that people over age 50 generally need higher amounts of vitamin D than younger people do.
Although the exact amount may be in question, the importance of vitamin D is not. Talk to your doctor for guidance on how to ensure you get the right amount for your needs.