Vitamin D supplements do not improve bone strength or prevent bone fractures in children, a major new clinical trial has found.
Figures show that around one-third of children suffer at least one bone fracture before the age of 18.
Doctors warn that this can lead to years of disability, and even a poor quality of life.
As a result, there has been growing interest in recent years in the potential for vitamin D supplements to increase bone strength or decrease the risk of bone fractures in children, given the vitamin’s role in promoting bone mineralization.
However, studies designed to confirm or deny these effects have not previously been conducted.
Researchers from Queen Mary University of London and the Harvard T.H. Chan School of Public Health conducted a trial whereby Mongolian children between the ages of six and 13 received a weekly vitamin D supplement over a period of three years.
They chose Mongolia as this is a setting where there is a particularly high bone fracture burden and where vitamin D deficiency is prevalent.
Their results, published in Lancet Diabetes & Endocrinology, show that while the supplements were highly effective in boosting vitamin D levels from the ‘deficiency’ range into the ‘normal’ range, they had no impact on fracture risk or on bone strength.
This has challenged widely held perceptions relating to the effects of vitamin D on bone health.
The trial – which represents the largest randomized controlled trial of vitamin D supplementation ever conducted in children – is likely to prompt scientists, doctors, and public health specialists to re-consider the impacts of vitamin D supplements.
“The absence of any effect of sustained, generous vitamin D supplementation on fracture risk or bone strength in vitamin D deficient children is striking,” said Dr. Ganmaa Davaasambuu, associate professor at the Harvard T.H. Chan School of Public Health.
“In adults, vitamin D supplementation works best for fracture prevention when calcium is given at the same time – so the fact that we did not offer calcium alongside vitamin D to trial participants may explain the null findings from this study.”
“It is also important to note that children who were found to have rickets during screening for the trial were excluded from participation, as it would not have been ethical to offer them placebo,” said Professor Adrian Martineau, Lead of the Centre for Immunobiology at Queen Mary University of London.
“Thus, our findings only have relevance for children with low vitamin D status who have not developed bone complications.
“The importance of adequate vitamin D intake for prevention of rickets should not be ignored, and UK government guidance recommending a daily intake of 400 IU vitamin D remains important and should still be followed.”
Produced in association with SWNS Talker