Yeditepe University Hospital Physical Medicine and Rehabilitation Specialist, who makes explanations about the function of vitamin D in the body and possible disorders that may arise in case of its deficiency, summarizes the effect of vitamin D in the body as follows: “The most well-known effect of vitamin D is on bone and muscle metabolism. Vitamin D regulates the absorption of phosphorus and calcium from the kidneys and intestines for the development of strong bones.”

Underlining that 80 percent of vitamin D occurs in the skin, the physician explains this process as follows: “Vitamin D is formed by the exposure of a cholesterol-based substance to UV rays. This cholesterol undergoes changes in two places, first in the liver and then in the kidney, after being exposed to the sun's rays and transformed into a vitamin D precursor. Finally, active vitamin D is formed.”

What are the Symptoms of Vitamin D Deficiency?

The physician, who also gives information about the diseases caused by vitamin D deficiency, says, “Vitamin D deficiency causes a bone metabolism disorder called osteomalacia, which manifests itself in the form of widespread bone and muscle pain in adults, and rickets in children. Vitamin D deficiency should be suspected in ongoing widespread bone and muscle pain. Studies have shown that a significant proportion of patients diagnosed with fibromyalgia and chronic low back pain have low vitamin D levels. In the advanced stages of vitamin D deficiency, patients may experience muscle weakness and related gait disturbances and even fractures in the bones.”

What Should Be Done for Vitamin D Deficiency?

Stating that sun exposure is the most important factor in the conversion of vitamin D, the physician says, “The period between March and October, the hours between 11-15, when the sun rays hit at a steep angle, is the most effective period for the conversion of vitamin D”, and continues as follows: “However, these are also the riskiest hours for skin cancer. It is enough to sunbathe below the knees and elbows for only 10-15 minutes, without using a protection cream.”

The physician also stated that the synthesis of vitamin D in brunettes is slower than blondes and that brunettes need to be exposed to the sun 3-6 times more than blondes due to their skin characteristics. Reminding that 20 percent of vitamin D is taken through food, specialists said that oily fish such as salmon and mackerel, fish oil, eggs, and mushrooms, which are rich in vitamin D, should be consumed especially in winter.

Underlining the functions of vitamin D other than bone and muscle metabolism in the body, specialists said, “Vitamin D receptors are found in many organs such as the heart, brain, breast, and prostate. The effect of vitamin D on different organs has been newly discovered. Especially recently, vitamin D deficiency has started to be counted among the causes of heart diseases, diabetes, depression, some types of cancer or infections.”

Reminding that vitamin D deficiency is more common in women, specialists stated that birth and breastfeeding periods are effective in this, and said that many patients apply to them with widespread postpartum pain. They emphasize that the elderly are another risk group due to changes in the skin and kidneys. They state that especially vitamin D has a significant effect on balance and if adequate intake is provided, falls can be prevented and the possibility of fractures in the bones can be reduced. Reminding that vitamin D deficiency can be detected with a simple blood test, the physician stated that if a deficiency is detected, supplemental vitamin D intake should be started under the control of a doctor.