Hypovitaminosis D is common in populations which consult GP's. Manu studies have been conducted which revealed high prevalence of severe hypovitaminosis in young people. risk factors were covered clothes, high BMI, dark phottype, precarity, no sunhbathing, no sun holidays, no sport outdoor. Quality of life was correlated with vitamin D levels. Patients with chronic musculo skeletal pains had very low level of vitamin D < 10 ng/ml for 25%. The supplementation cured the pains for more than 50 % of the patients and decreased the consumption of medicines and care. It will be be very important to consider this problem of public health for young people.