Vitamin D is called the sunshine vitamin for good reason. Not only does your body make vitamin D when your skin is exposed to the sun, we also know vitamin D can ward off many health problems.
Vitamin D is a naturally occurring compound that regulates the body’s use of calcium and phosphorus. It’s crucial for the formation of bone and teeth.
Because vitamin D is so important in bone growth, some researchers have wondered if supplements can help joint pain.
A small study of five people with vitamin D deficiency noted that pain symptoms went away when the participants took vitamin D supplements. Another study predicted that adults with a vitamin D deficiency who are older than 50 are more likely to develop pain in their hip and knee joints. The study also noted that the pain is more likely to get worse if the deficiency isn’t treated.
Another study looked at vitamin D levels in people who have rheumatoid arthritis (RA), an autoimmune condition that causes the body to attack its own joints. The study found that most of the participants had low vitamin D levels. The researchers concluded that the low vitamin D levels were a complication of RA. Other studies have concluded that people with RA have low vitamin D levels from their corticosteroid medications.
However, a study of postmenopausal women (a group that frequently experiences joint pain) found that taking daily vitamin D3 and calcium supplements did not improve joint pain.
In adults, vitamin D wards off osteomalacia (soft bones) and osteoporosis (loss of bone mass). People with vitamin D deficiency are more likely to experience infection and insulin resistance. Some studies have linked vitamin D deficiency to coronary artery disease. However, not enough research exists to confirm the link.
For most people, the recommended daily allowance of vitamin D is 600 international units (IU). Babies up to 1 year of age need only 400 IU, and adults older than 70 should have 800 IU. To get your recommended daily allowance, make sure you eat the right foods and get decent sunlight.
Eat the right foods
Food is the best way to get vitamin D. Fish, dairy, and fortified cereal are good sources.
Sources of vitamin D
|Food||IU per serving|
|Swordfish, cooked, 3 ounces||566|
|Salmon (sockeye), cooked, 3 ounces||447|
|Tuna fish, canned in water, drained, 3 ounces||154|
|Orange juice fortified with vitamin D, 1 cup||137|
|Milk, nonfat, reduced fat, and whole, vitamin D-fortified, 1 cup||115-124|
|Liver, beef, cooked, 3 ounces||42|
|Egg, 1 large||41|
Get some sunlight
Sun exposure is the second significant source of vitamin D. Ultraviolet light starts a chemical reaction in the skin that produces a usable form of vitamin D. How much vitamin D your body produces changes with the environment and how well your skin absorbs vitamin D. Those with darker skin need more sun exposure.
The right dose of sunshine for getting vitamin D is hard to estimate. However, depending on skin color and how well you absorb vitamin D, aim for about 5 to 30 minutes of exposure between 10 a.m. to 3 p.m. at least twice per week. The exposure should be to your face, arms, legs, or back, without sunscreen. Sunscreens with a sun protection factor (SPF) of 8 or higher block vitamin D-producing UV rays. For some people, a supplement may be needed regardless of amount of time in the sun. Talk to your health care practitioner about your vitamin D levels.
If you work an office job or live in an area that doesn’t have a lot of sun, consider replacing the lightbulbs in your home with vitamin D bulbs.
It’s very rare to get too much vitamin D. But overdose can potentially be very serious. Vitamin D toxicity is most likely to be caused by taking too many supplements.
Vitamin D toxicity has developed when people take 50,000 IU per day of vitamin D for several months. This is more than 80 times the typical adult recommended dietary allowance of 600 IU. People who have certain health problems may need less vitamin D than the average person and be more susceptible to excess levels.
Your body regulates the amount of vitamin D it gets from sunlight and food. It’s difficult to get too much vitamin D from the sun. Too much time in the sun interferes with your body creating vitamin D. The biggest risk of sun exposure is skin cancer. You should wear sunscreen with an SPF of at least 15 before going outside into the sun. Sunscreen should be reapplied every two hours.
Vitamin D toxicity can lead to a buildup of calcium in your blood. This is a condition known as hypercalcemia. The symptoms include:
- poor appetite
- frequent urination
- kidney problems
The primary treatment is to lower or discontinue use of vitamin D supplements. In extreme cases, intravenous fluids or medications may be necessary.
People who have low levels of vitamin D often have joint pain. Vitamin D supplements may treat joint pain in some people who have a vitamin D deficiency. However, research doesn’t support that people with healthy levels of vitamin D take should take these supplements for joint pain.