Authors of an article in the Lancet highlight how rickets – often considered a disease of the past – is still a global public-health problem today. The authors propose the use of vitamin D supplementation for pregnant women and among children up to the age of puberty to prevent a resurgence of the disease.

Vitamin D is essential for healthy bone formation during childhood; sources of vitamin D include natural synthesis as a result of skin exposure to sunlight, and limited food sources that include fortified cereals and oily fish.

Brian Wharton from the Institute of Child Health, London, and Nick Bishop from the University of Sheffield, UK, outline some possible reasons for an increase in vitamin D deficiency and rickets. They include vitamin D deficiency in breastfeeding mothers; reduced production of the vitamin in the skin because of fear of skin cancer; and the high prevalence of rickets in immigrant groups in more temperate regions.

Nick Bishop comments: “A safety net of extra dietary vitamin D should be re-emphasised, not only for children but also for pregnant women. The reason why many immigrant children in temperate zones have vitamin D deficiency is unclear. We speculate that in addition to differences in genetic factors, sun exposure, and skin pigmentation, iron deficiency may affect vitamin D handling in the skin or gut or its metabolism.”

Vitamin D deficiency may occasionally occur in people on a vegetarian diet who do not drink milk products, or in people who are lactose intolerant. A dietary lack of calcium and phosphorous (rather than a lack of vitamin D) may also play a part in the nutritional causes of rickets.

Great Ormond Street Hospital, Oct 24, 2003