Vitamin D deficiency in Tunisia

Abstract

This study seeks to estimate the status of serum 25-hydroxyvitamin D [25(OH)D] in a healthy section of the population in Tunisia and to compare the achieved results with other published data. A transverse descriptive inquiry was carried out between January and March 2002. Three hundred and eighty-nine subjects aged 20–60 years were included in the study. A questionnaire was used to investigate clinical characteristics: sunlight exposure to ultraviolet light and, for women, parity, breast feeding, whether or not they wore the veil, and menopause. A dietary investigation estimated calcium and vitamin D intake. Morning fasting blood was collected from each subject for the measurement of the following parameters: serum calcium, phosphorus, albumin, alkaline phosphatase, 25(OH)D, parathyroid hormone (PTH). Hypovitaminosis D was defined by a cut-off of 37.5 nmol/l. The population studied was largely female, for the greater part housewives. The accumulated prevalence of hypovitaminosis D was 47.6%, increasing with age. Hypovitaminosis is highly prevalent in women (P<0.001). Multiparity, menopause, wearing the veil, and calcium and vitamin D dietary intake are factors associated with hypovitaminosis D (P<0.05). Analysis of logistic regression shows that only multiparity and vitamin D dietary intake are independent predictive factors. The status of serum 25(OH)D in Tunisia resembles that in southern European countries rather than in Middle Eastern countries. Insufficient vitamin D diet intake, higher parity and wearing the veil explain this deficiency in Tunisia. Dietary enrichment or supplementation by vitamin D and a more outdoor lifestyle, especially for older people, should be seriously considered as a way to reduce this deficiency in Tunisia.