Addressing vitamin D deficiency among veiled pregnant women in Australia.

To the Editor: It is noteworthy that Sir Edward Mellamby discovered rickets while working on dogs raised exclusively indoors (without sun exposure), and that he mistakenly attributed the disease to a dietary (vitamin) deficiency rather than to a sunlight-activated steroid. (1) We now know that the dictum 'light equals vitamin D' is much closer to the truth than Mellamby's dietary experiments of 1919-1920 suggested. In Australia, as in most Western nations, the approach to the management of vitamin D among some high-risk groups, such as elderly people in residential care, dark-skinned people, and people with skin conditions where avoidance of sunlight is advised, is fairly straightforward. However, addressing vitamin D deficiency among veiled pregnant women is an issue coloured by politics, religion and culture.

Although the role of vitamin D in preventing osteomalacia and rickets are well known, it is the new findings suggesting its role in maintaining optimal muscle function, and in preventing diseases such as multiple sclerosis, diabetes and hypertension that have renewed interest in its functions as a governor of the body's health. (2,3) About 90% of vitamin D is generated from the effect of sunlight on skin. Studies in Australia and most Western countries demonstrate that veiled pregnant women are at high risk of vitamin D deficiency because of their garments' impairment of absorption of ultraviolet B light from the sun. Children born to such mothers are also at greater risk of rickets and growth impairment. (4)

Australian health authorities are faced with several dilemmas. First, in a country with the world's highest incidence of sun-related skin cancer, (5) encouraging limited sun exposure in order to enhance vitamin D levels among veiled (i.e. Muslim, and to a lesser extent Hindi) pregnant mothers while propagating antiskin cancer 'slip, slop, slap' message for other Australians is problematic. To succeed, adequate public education on why veiled pregnant women might be at risk of vitamin D deficiency is essential, as well as reasonable estimates of the amount of sun exposure required, areas of skin that need to be exposed, ideal time periods, and the duration of sun exposure in summer and winter months. (6)

Second, a recent study of 316 men and women in Lebanon showed that veiling was an independent risk factor for low vitamin D intake, and that increase in sun exposure among veiled women (with dietary and vitamin D supplementation) is an appropriate approach to facilitate adequate vitamin D levels. (7) However, it might be difficult to reconcile the sun exposure message for veiled women with a general political opposition to veiling (i.e. hijab and burka) by Western nations like France, Belgium and the Netherlands. For instance, the Netherlands is currently drafting legislation to prohibit the wearing of burka and hijab 'in specific situations' on grounds of public safety. (8) Thus, it might be problematic for Australian and Western public health agencies to advocate unveiling to pregnant Muslim women under such a climate of mutual suspicion. To succeed, this initiative must have the support of core Muslim leaders nationwide, and would involve extensive consultations with families, women's groups and Muslim associations, in order to balance respect for Muslim female modesty customs with the attainment of a vitamin D public health goal.

Third, studies have suggested that breast milk has low levels of vitamin D, although this does not seem to affect infants' bone mineral content significantly. (9,10) Although there is little scientific evidence to back current recommendations of minimum vitamin D intake in both infants and pregnant or lactating mothers, (11) such studies, together with rising vitamin D deficiency in certain US population groups, has recently led to American paediatricians recommending 200 IU/day of vitamin D for all infants and children. (12) Hollis and Wagner (13) posit that the current daily recommended intake for vitamin D of 400 IU is irrelevant to the nutritional status of mothers and infants. They recommend maternal vitamin D intakes of 4000 IU or greater for nursing mothers, a level which was shown to be safe and which would supply breast-feeding infants, through milk transfer, with adequate vitamin D to prevent vitamin D deficiency disorders. There are recent calls by Australian researchers for health authorities to reconsider recommendations for Vitamin D supplements in predominantly breast-fed infants. Such initiatives might negatively impact on global initiatives to promote breast-feeding, (14) as marketers of breast milk substitutes may stress the issue of low vitamin D levels in breast milk as a strategy to increase the popularity of bottle-feeding. It is probably more appropriate to promote guidelines for adequate sun exposure for infants and mothers, and high-dose maternal calcium/vitamin D supplementation, (13) rather than introduce policies that might impair the effectiveness of policies and practices that promote breast-feeding.

Fourth, compliance with vitamin D supplementation intake is a major issue among high-risk pregnant women and their children in Australia. A recent study indicated that a quarter of vitamin D deficient postnatal women attending an Australian hospital were not prescribed vitamin D supplementation as per existing policy, and half did not take prescribed medication correctly. (15) About 90% of the vitamin D deficient women in this study were Muslims, and it was determined that noncompliance was partly because of the belief among the women that the vitamin supplements contained pork products. Dispelling such misconceptions must start with the manufacturers and medical authorities certifying, on the cover of the supplements, that no pork products were used in its manufacture. Also important is the need to develop comprehensive compliance management systems with regards to vitamin supplementation, balanced diet and adequate sun exposure.

Nutritionists, midwives, obstetricians, paediatricians, and other health workers need to be aware of the religious, cultural, behavioural and political complexities with regard to the issue of addressing vitamin D deficiency in veiled pregnant women, and take such complexities into consideration, in planning and implementing programs to reduce the prevalence of vitamin D deficiency among this cohort. Securing the cooperation of opinion leaders in Muslim/Hindi communities in the development and implementation of such programs is paramount to achieving effective outcomes.

ACKNOWLEDGEMENT

I thank Ms Olu Adebajo, RN, of St George Hospital, Sydney, for encouraging me to submit this manuscript.

Niyi Awofeso, PhD

Professor, School of Public Health and Community Medicine, University of New South Wales, Sydney, New South Wales, Australia

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