While 10-20% of vitamin D is taken with food, the majority (80-90%) is synthesized in the skin under the influence of sunlight. Direct sunlight contact with the skin is required for synthesis. Sunbathing behind glass and tulle prevents the synthesis of vitamin D. The use of sunscreen creams with a factor level of 15 or higher prevents the formation of vitamin D by preventing the sun’s rays from reaching the skin by 99%. In the latitude of our country, the most effective synthesis occurs between May and November and between 10-15 hours. In case of exposure to sunlight on the whole body, sufficient vitamin D synthesis can occur within 15-45 minutes.
Another important source of vitamin D is food. Foods containing vitamin D naturally include fatty fish (salmon, tuna, mackerel, sardines…), fish oil, butter, milk, oats, sweet potatoes, egg yolks, oils, liver, parsley, nettle, clover.
Vitamin D deficiency is common, especially in winter. Inadequate sunbathing, low consumption of foods rich in vitamin D, insufficient absorption from the intestines for various reasons, and disorders of organs such as liver and kidney that play a role in vitamin D metabolism.
Vitamin D deficiency is detected by measuring vitamin D levels in individuals at risk. People at particular risk; those who spend most of their time indoors, those who are bedridden/home-bound, those who stay in nursing homes/nursing homes, those with liver disease, those with kidney disease, those with osteoporosis, those with bone fractures, those with low blood calcium, those with low blood phosphorus, those who are obese, those with hyperparathyroidism, those who take cortisone Vitamin D levels should be checked in those who have a closed style of clothing. Serum 25(OH) vitamin D level should be above 30 ng/ml (75 nmol/L).
Although most patients do not have any signs and symptoms, severe and long-term vitamin D deficiency may develop osteoporosis, widespread bone-muscle pain, bone tenderness, muscle weakness, difficulty in walking and bone fractures.
If the vitamin D level is below 30 ng/ml, treatment is required.
The goal of treatment is to keep the serum 25(0H) vitamin D level between 30-50 ng/ml.
The daily requirement of vitamin D in adults has been determined as 800-1500 IU.
Adequate calcium intake (1000 mg daily) should be provided together with vitamin D.