Vitamin D and Its Sources
Vitamin D is a fat-soluble vitamin that is produced in the body when our skin is exposed to sunlight. It is available from food and supplements in both forms — vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).
Determining Your Vitamin D Needs
How much vitamin D you need depends on your age, health issues, and where you live. Talk to your doctor or dietitian.
Sources of Vitamin D
You can get vitamin D from fatty fish like salmon, fish liver oils, and dairy products. If you are unable to eat these foods, take a supplement or ask your health care provider for a blood test.
Importance of Vitamin D for Bone Health
Getting enough vitamin D is critical for bone health and may help prevent fractures. It also helps the body absorb calcium, a building block for strong bones.
Sunlight as a Source of Vitamin D
The main source of vitamin D is sunlight; you need about 20 minutes a day in the sun to produce adequate levels of vitamin D. You can also get vitamin D from supplements, especially if you are a woman or have other conditions that reduce your ability to absorb calcium.
Vitamin D and Reduced Cancer Risks
Studies have shown that a higher level of vitamin D is associated with lower risks of certain cancers. For example, those who live in southern or equatorial areas and have more exposure to the sun are less likely to develop colon, breast, and prostate cancers.
Vitamin D and Cardiovascular Health
It could also reduce your risk of cardiovascular disease. It could help your body use insulin better and help prevent type 2 diabetes if you have been diagnosed with this condition or are at risk for developing it. It might also decrease your risk of heart attack or stroke if you have high blood pressure or are overweight.
Additional Vitamin D Needs
Your body can make vitamin D from sunlight and foods such as eggs, beef liver, and cheese. Most people can get sufficient vitamin D from the sun and foods, but some people — including infants, those with celiac disease, and those who have had gastrointestinal tract surgery — need more.
Supplementation for Vitamin D
Unless you live in an area that gets a lot of sunshine, you need to take supplements to get enough vitamin D. In the United States, the FNB recommends 400 IU of vitamin D daily for healthy adults and 800 IU of vitamin D per day for those aged 70 or older, if they have health problems such as celiac disease.
Vitamin D and Brain Function
There is also a lot of evidence that suggests vitamin D helps improve brain function. Scientists have found that it protects neurons, reduces inflammation within the brain, and improves mental acuity and reaction time.
Including Vitamin D in Your Diet
Vitamin D is an important part of a healthy diet and should be included in every meal. It is most easily absorbed through the skin, but it also can be ingested in a variety of forms, including pills, capsules, and drops. You can also get vitamin D from a variety of foods, including milk, eggs, and other dairy products. It is often fortified in orange juice, yogurt, and cereal.
