With the increased popularity of using sunscreens with high sun protection factors (SPFs) to prevent sun damage and skin cancer, Americans are unknowingly increasing their risk of becoming vitamin D deficient. The National Center for Health Statistics published in March that 36% percent of American adults surveyed from 2001-2006 were at risk of vitamin D deficiency or inadequacy. Additionally, the Journal of Pediatrics published in 2009 that 70% of children in the US are not getting enough vitamin D.
We all know that unprotected sun exposure can damages our skin and cause skin cancer, but sunlight is also used by our bodies to produce Vitamin D. When using SPF, our bodies have a more difficult time absorbing vitamin D from the sun. Even Using SPF 8 cuts the amount of vitamin D absorbed from sunlight by 95%. Higher SPFs reduce absorption to almost zero. Vitamin D is essential to our bodies because it aids in the absorption of calcium. Too little vitamin D, and the body has a hard time absorbing enough calcium, leading to weak bones, osteoporosis, and rickets. Vitamin D is also important to the immune system. People who are deficient in vitamin D can be more prone to infection.
Are you at an increased risk? Since natural sources of vitamin D come from animal products, strict vegetarians and vegans can be more likely to become vitamin D deficient. Also likely to be at risk are those who suffer from Crohn’s disease, cystic fibrosis, and celiac disease. These diseases affect the intestine’s ability to absorb vitamin D from food.
So how do you know if you are vitamin D deficient? Unfortunately, symptoms of a vitamin D deficiency are subtle, but if you are experiencing bone pain or muscle weakness, you could have cause for worry. The most precise way to measure your vitamin D level is the 25-hydroxy vitamin D test, a blood test performed by your doctor. Normal levels of vitamin D range from 30 to 74 nanograms per milliliter. Levels lower than 30 indicate a vitamin D deficiency.
Vitamin D fortified Milk has long been relied upon to provide Americans with the vitamin D that they need. However, in 2001 Cornell University sampled 648 cartons of vitamin D fortified milk in New York state. As a result, researchers at Cornell found that 46.3% of the milk was under fortified and did not contain the 400 international units (IU) per quart as listed on the label. Other sources of vitamin D include dairy products such as yogurt and cheese and fatty fishes like tuna and salmon. Since the natural sources of vitamin D are few, it is unlikely that you can eat enough of these foods on a regular basis to satisfy your body’s vitamin D requirements. The National Institutes of Health’s Office of Dietary Supplements recommends 600 IU of vitamin D daily for audlts and children. However, many doctors speculate that we actually need closer to 1000 IU in order to prevent brittle bones and osteoporosis. Web MD recommends that both adults and children supplement with 1000 IU daily.
When choosing a vitamin D supplement, there are two important factors to consider.
- Choose D3. Vitamin D supplements that contain the naturally active form of vitamin D, D3, are much more effective than ones that contain vitamin D2.
- Look for a vitamin D supplements that contain vitamin K2, which can help maintain bone density. Taking vitamins D3 and K2 together can help improve the absorption of calcium.
So remember, while the use of sun protection is rising, so is the risk of vitamin D deficiency. However, rather than exposing ourselves to sun damage, it is safer to take a vitamin D supplement. It is hard to be certain exactly how much vitamin D we get from our diets alone, and supplementation can make sure that we are receiving the nutrients that our bodies need. Remember to consult with your primary care physician before starting a new supplementation plan.