Known as the Sunshine Vitamin, vitamin D plays a vital role in healthy function of the human body. The body uses it to absorb calcium (which keeps bones strong) and block the release of parathyroid hormone (which prevents bone reabsorption). It may also have a role in muscle and immune system function, and further benefits are currently being studied.
Your body produces vitamin D when your skin is exposed to sunshine. The vitamin also occurs naturally in foods like fish and egg yolks, although it’s hard to get enough vitamin D from diet alone.
If you’re not getting enough vitamin D from food and the sun, your body will tell you. Make sure you’re on the lookout for these symptoms of deficiency:
- Increased susceptibility to sickness
- Bone and lower back pain
- Slow healing
- Hair loss
Certain medical conditions can precipitate deficiency, among them obesity, Crohn’s disease, celiac disease, and kidney and liver diseases. All block either the absorption, processing, or storage of vitamin D. If you are older or have dark skin you are also at elevated risk of vitamin D deficiency.
Even without symptoms, having low vitamin D increases your risk of developing illnesses including cardiovascular disease, bone loss, and cancer. Ask your doctor about supplements if you suspect you’re vitamin D deficient.