Where do we get vitamin D?
We get Vitamin D from two sources. We can manufacture Vitamin D when our skin is exposed to the sun. And we can get it in our diet. In the United States, milk is fortified with vitamin D. There are not a lot of other easy dietary sources of Vitamin D. It is found in Cod Liver oil and a small amount in eggs.
What happens if our Vitamin D level drops too low?
In children, bones will not form properly, and will be deformed and too soft. This condition is called rickets, and is very rare. In older adults the bones will become weak and can become tender. There can also be widespread muscle aching. If bones become too thin it is called osteoporosis and can lead to fractures. Hip fractures and spinal compression fractures are the most common, but any bone can be involved.
Many other diseases have been found to be associated with Vitamin D deficiency, including several kinds of cancers, high blood pressure, heart attacks and diabetes.
What is a normal Vitamin D level?
This is a question currently under intense debate in the medical and scientific community. Some studies in recent years have suggested a level of 30 ng/ml of Vitamin D is needed for optimal health.
Only about 30 percent of elderly individuals are actually in this range, meaning that using this standard a full 70 percent of older adults would be found to be Vitamin D deficient. Over the past few years, this has resulted in a very large number of people being found to be “Vitamin D deficient”, and started on Vitamin D supplements.
Just a few weeks ago, the National Institute of Medicine compiled a large review of all available studies and concluded that for most individuals, a Vitamin D level of 20 ng/ml was safe, and that 20 ng/ml should be considered the cut off for “normal”. Using this lower cut off, many fewer individuals are found to be deficient. In the medical and scientific community, there is likely to be a lot of debate, and hopefully further studies in the next few years to clarify which standard should be used.
Who is at risk for Vitamin D deficiency?
Most children and middle aged adults who get even an hour or two of sun exposure per week will get adequate Vitamin D without any supplementation. Individuals at high risk for deficiency include those with very low sun exposure, the elderly (because our intestinal absorption goes down as we age), those with cystic fibrosis or who have had gastric bypass surgery, other chronic intestinal disease or kidney failure. Infants who are exclusively breast fed are also at risk.
Who should be on Vitamin D supplements?
If you think you are in a group at high risk for Vitamin D deficiency, you can ask your doctor to check your levels the next time you visit with them. Most people who need a little extra can do fine with an over the counter preparation of 500 or 1000 IU per day.
If your level comes back dangerously low, your doctor may need to prescribe a higher dose prescription strength Vitamin D medication for you.