You can get the vitamin from food mainly because it's been added; few foods are natural sources of vitamin D and by taking supplements many doctors recommend taking IU of vitamin D 3 a day. But vitamin D is also produced by the body in a complex process that starts when rays in the invisible ultraviolet B UVB part of the light spectrum are absorbed by the skin. The liver, and then the kidneys, are involved in the steps that eventually result in a bioavailable form of the vitamin that the body can use.
The latitude where you live. At higher latitudes, the amount of vitamin D—producing UVB light reaching the earth's surface goes down in the winter because of the low angle of the sun. In Boston, for example, little if any of the vitamin is produced in people's skin tissue from November through February.
Short days and clothing that covers legs and arms also limit UVB exposure. The air pollution where you live. Carbon particulates in the air from the burning of fossil fuels, wood, and other materials scatter and absorb UVB rays.
Ozone absorbs UVB radiation, so holes in the ozone layer could be a pollution problem that winds up enhancing vitamin D levels. Your use of sunscreen — in theory. Sunscreen prevents sunburn by blocking UVB light, so theoretically, sunscreen use lowers vitamin D levels. But as a practical matter, very few people put on enough sunscreen to block all UVB light, or they use sunscreen irregularly, so sunscreen's effects on our vitamin D levels might not be that important. An Australian study that's often cited showed no difference in vitamin D between adults randomly assigned to use sunscreen one summer and those assigned a placebo cream.
The color of your skin. Melanin is the substance in skin that makes it dark. It "competes" for UVB with the substance in the skin that kick-starts the body's vitamin D production.
As a result, dark-skinned people tend to require more UVB exposure than light-skinned people to generate the same amount of vitamin D. The temperature of your skin. Warm skin is a more efficient producer of vitamin D than cool skin. So, on a sunny, hot summer day, you'll make more vitamin D than on a cool one. However, your doctor might recommend higher doses of vitamin D if he or she is checking your blood levels and adjusting your dose accordingly.
Also, be cautious about getting large doses of vitamin A along with the D in some fish oils.
Vitamin D deficiency: Causes, symptoms, and treatment
Vitamin A can also reach toxic levels and can cause serious problems. The goals of treating and preventing the lack of vitamin D of treatment and prevention are the same—to reach and keep an adequate level of vitamin D in the body.
Your healthcare provider will let you know if you need to take or keep taking vitamin D supplements. If so, they will also let you know how much you should take. You might also want to consider.
Eating more foods that contain vitamin D : See the vitamin D food sources table included in this article. Keep in mind that foods alone usually don't meet the daily recommended levels of vitamin D. You might need more sun exposure especially in early spring and late fall if. The use of sunscreen, and standing behind a window, prevents vitamin D from being produced in the skin. However, you should remember that too much sunshine increases the risk of skin cancer and ages the skin.
That is why taking an appropriately dosed D supplement is far safer than intentionally getting routine sun exposure. Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Vitamin D Deficiency Getting enough, but not too much, vitamin D is needed to keep your body functioning well.
Vitamin D helps with strong bones and may help prevent some cancers. Symptoms of vitamin D deficiency can include muscle weakness, pain, fatigue and depression.
9 things that can undermine your vitamin D level - Harvard Health
To get enough D, look to certain foods, supplements, and carefully planned sunlight. Why is vitamin D so important? This vitamin has many functions, including: Keeping bones strong: Having healthy bones protects you from various conditions, including rickets.
Rickets is a disorder that causes children to have bones that are weak and soft. It is caused by a lack of vitamin D in the body.
You need vitamin D so that calcium and phosphorus can be used to build bones. In adults, having soft bones is a condition called osteomalacia. Absorbing calcium: Vitamin D, along with calcium, helps build bones and keep bones strong and healthy. Weak bones can lead to osteoporosis, the loss of bone density, which can lead to fractures. Vit.