Vitamin D status in apparently healthy adults in Kashmir Valley of Indian subcontinent

Abstract

Background: The worldwide prevalence of vitamin D deficiency is reported to be high. Objectives: To assess the vitamin D status in apparently healthy adults in Kashmir valley by measuring serum 25-hydroxyvitamin D (25 (OH) D). Methods: 92 healthy natives (64 men and 28 non-pregnant/non-lactating women, aged 18-40 years), residing in Kashmir for at least last 5 years and not having any suggestion of systemic disease, were selected for this study. The samples were collected throughout the year in both summer and winter months. Vitamin D deficiency was defined as a serum 25 (OH) D concentration of <50 nmol/l and graded as mild (25-50 nmol/l), moderate (12.5-25 nmol/l) and severe (<12.5 nmol/l). Results: Body mass index, total energy intake, and other nutritional parameters were comparable among subjects in different groups. Overall 76 (83%) of the subjects studied had vitamin D deficiency - 25%, 33%, and 25% had mild, moderate, and severe deficiency, respectively. 49 of the 64 males and all but 1 of the 28 females were vitamin D deficient. The prevalence of vitamin D deficiency ranged from 69.6% in the employed group to 100% in the household group. Vitamin D deficiency was equally prevalent in subjects from rural and urban areas. Serum calcium and phosphorus values were comparable in subjects with and without vitamin D deficiency, while daily intake and urinary excretion of calcium were significantly lower in the former. Vitamin D deficient subjects had a significantly lower mean weekly exposure to sunlight. Conclusions: In spite of abundant sunlight, healthy individuals in Kashmir valley are vitamin D deficient, particularly women. Serum 25 (OH) D concentrations are significantly related to sun exposure.