Mercy Sports Medicine

Vitamin D and the Active Person

By: Brian L. Mahaffey, MD, MSPH, FAAFP

For years, many people felt that dairy consumption and sun exposure provided all of a body’s needs for Vitamin D. We now know that most people do not produce enough Vitamin D with sun exposure or consume enough in their diets. Darker skin coloration and sunscreen use may block skin production.

The accepted level of Vitamin D is above 30 ng/ml in blood. Studies have shown that active people perform better if the level is maintain above 50 ng/ml. 50-70% of children and adolescents have low levels. 75% of Caucasians and 90% of African Americans and Latinos are deficient. As we get older, the level of deficiancy increases.

Vitamin D is a natural steroid hormone that affects multiple sites in your body. When Vitamin D levels are normal, muscles maintain their strength and size better. Your nervous system works better, with improved reaction time, balance and coordination. Endurance is also improved, and your immune system works better to protect against inflammation and infections. All of these effects help you perform.

With athletes, there are two overall effects that are very beneficial. First, numerous studies show improved performance across the board. Second, athletes show better recovery from activities and fewer or less severe injuries overall.

What should you do to help with overall performance, injury prevention and health? The first step is to check your Vitamin D level. If it is below 30 ng/ml, it is appropriate to take a prescription strength 50,000 International Units (IU) weekly for eight weeks, then an over-the-counter tablet up to 4,000 IU daily. This can be safe and effective in adolescents as well. Studies have shown that up to 10, 000 IU daily in adults will not cause toxicity. Vitamin D3 is the best source to use as a supplement. It is very important to recheck levels to make sure they increase and maintained long-term.

At Mercy Sports Medicine, we are concerned not only with improved performance but with preventing injury and maintaining health. If you are active and have been diagnosed with a stress fracture, have recurrent musculoskeletal pain, or frequent illness, it is best to check your Vitamin D level. If you are a competitive athlete, monitoring your Vitamin D level may help you improve performance and reduce injuries.

Brian Mahaffey, MD, MSPH, FAAFP is director of Mercy Sports Medicine and a team physician with The St. Louis Cardinals. You can reach Dr. Mahaffey at 314.325.3068