This article was written by Vera Tweed and originally published in Amazing Wellness magazine. It has been edited for What’s Good. 

Sometimes called the ‘sunshine vitamin,’ vitamin D is produced in your skin when it’s exposed to sunlight’s UVB rays. Technically a family of compounds that includes vitamins D1, D2, and D3, this fat-soluble vitamin is known for several important functions. Its main claims to fame: regulating the absorption of calcium and phosphorus and facilitating normal immune system function. Getting ample D is crucial for the normal growth and development of bones and teeth, and to improve resistance against certain diseases.

However, D’s story doesn’t end with bones and immunity! According to a review published in the Journal of the American Academy of Orthopaedic Surgeons, vitamin D supplementation may help boost performance and muscle strength, and reduce injury in athletes.

Research suggests the vitamin plays a role in protein synthesis, muscle function, and the regulation of our skeletal muscle. (Specifically, it seems to help increase the size and amount of type-II muscle fibers, which are responsible for strength and power.) In one study, athletes who took vitamin D supplements increased upper and lower body strength more than those who took a placebo.

Related: 7 Signs You Have A Vitamin D Deficiency

What’s more, a study of vitamin D-deficient athletes found that those who took 5,000 IU per day increased their vertical jump height more than those who didn’t. Plus, U.K. Royal Marine recruits with the lowest D levels had a 60 percent higher incidence of stress fractures than those with the highest levels. “With higher serum levels of vitamin D playing a role in muscle strength, injury prevention, and sports performance, it’s essential for individuals to ensure they’re getting an adequate amount of vitamin D,” said lead study author and orthopedic surgeon Geoffrey D. Abrams, M.D., of Stanford University.

Considering about 77 percent of Americans are estimated to be vitamin D-deficient, this information matters for any of us trying to live an active, healthy life. The U.S. government recommends adults get 600 IU of vitamin D every single day, though some people may need more based on their current levels and where they live. Aside from sunlight exposure, you can also find it in certain foods, including fatty fish, eggs, and UV-treated mushrooms. If you’re concerned about your D levels, talk to your doctor about checking your levels with a blood test and consider adding a supplement to your routine.