Possible side effects of low levels of vitamin D include muscle and joint pain or weakness, bone pain, fatigue and depression. Vitamin D deficiency does not often produce noticeable symptoms, so most people are not aware they have low levels of the vitamin, explains Healthline. Vitamin D deficiency can easily be identified through a standard blood test.
Low vitamin D levels can pose serious health risks, such as rickets, increased risk of death from cardiovascular disease, cognitive impairments, asthma and cancer, according to WebMD. Reduced levels of the vitamin are also associated with osteoarthritis and autoimmune disorders, adds Healthline. Dementia, prostate cancer, erectile dysfunction and schizophrenia have also been linked to vitamin D deficiency, notes Nancie George for Everyday Health.
Treatment for vitamin D deficiency typically involves taking vitamin D supplements. Researchers have found the disorder cannot be corrected by simply adding more vitamin D-rich foods to the diet, as the level of vitamin D in the foods is too low to offset the deficiency, states Healthline. People who adhere to a vegan diet or have limited exposure to sunlight are particularly at risk of low levels of vitamin D. People who are obese, have a digestive or chronic kidney disease or are older than 65 may also be at risk.