My athletes scoff when I tell them to take a daily vitamin D3 supplement. They can’t see how they could possibly need vitamin D when they eat enough cheese to sustain the French Alps. But even if you eat yogurt every day, you can still be vitamin D deficient.
A March 2009 Archives of Internal Medicine study found that more than three-quarters of adults are vitamin D deficient. And to all you athletes out there, a 2008 study at the Cooper Clinic in Dallas found that 75% of runners averaging 20 miles a week have below-normal vitamin D levels.
It’s important to pay attention to your vitamin D intake. Here’s why.
Vitamin D for Athletes
Vitamin D is best known for maintaining bone health. It helps the body absorb calcium from food and supplements. If you suffer from chronic stress fractures, vitamin D supplements can help decrease your risk of future stress fractures.
Vitamin D may significantly benefit performance during training. A February 2009 Journal of Clinical Endocrinology & Metabolism study found that adolescents with higher levels of vitamin D can jump higher, quicker and with greater power than those with lower vitamin D levels.
Where Can I Get Vitamin D?
Vitamin D is unique in that it can be absorbed through the foods we eat, but it can also be absorbed through exposure to sunlight. It’s present in foods such as fatty fish such as salmon or sardines, mushrooms, egg yolk and dairy products. Vitamin D needs to be consumed with adequate dietary fats to be absorbed, so stick to full-fat yogurt to get the full effect.
If you are looking towards the sunshine for your vitamin D needs, 15-30 minutes of direct sunlight is enough to hit your daily requirements. However, there are limitations. First, indoor sun exposure, such as sunlight through a window, will not produce vitamin D. Second, your vitamin D deficiency doesn’t decrease your risk of skin cancer. You still should wear sunscreen to ward off the sun’s harmful effects even though sunscreen reduces the body’s ability to absorb vitamin D from sunlight. Lastly, the sunshine can’t work its magic if you’re layered up during the colder, winter months. Vitamin D absorption can only happen when sunlight directly hits our skin.
A final way to get vitamin D is through supplements. Vitamin D supplements can be found either on their own or combined with another product, usually calcium. Supplements are usually found in one of two forms: D2 or D3. D3 is the natural form of vitamin D that the body makes from sunlight and therefore is usually the preferred supplement. However, both forms are sufficient at increasing vitamin D in the blood.
Don’t Overdo it
It’s possible to go overboard with vitamin D. While it is unlikely to get too much vitamin D from food or sunlight, a vitamin D overdose can happen with supplementation. Signs of vitamin D toxicity include nausea, vomiting, poor appetite, weight loss, constipation, weakness, confusion, disorientation and problems with heart rhythm.
Too much of any good thing is a bad thing so it is important to maintain a healthy overall diet and only take supplements as recommended.