Vitamin D supplements do nothing to boost bone strength in normal healthy adults and are not needed, new research has concluded.
The New Zealand-led research was published on Friday the British medical journal The Lancet.
The study reviewed results of 23 international studies, involving more than 4000 participants with an average age of 59, during the past 30 years.
The study was led by Auckland University medical researcher Ian Reid who says Vitamin D supplements did not boost bone mineral density in adults with normal levels of the vitamin in their blood. "The idea that more is better is not true when it comes to Vitamin D and bone health."
Professor Reid says this advice applies to all older people, including menopausal women, and the only ones who would need supplements are the frail, those confined to rest homes, women who are veiled, and some dark-skinned people.
Children lacking a good diet, especially dark-skinned children, may also need supplements to prevent rickets.
Professor Reid says Vitamin D testing is a $10 billion - $20 billion a year industry in the United States and the money would be better spent targeting supplements to those who need them.
He says testing in Auckland has been reduced for this reason.
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