
You may be aware of the recent debate about whether or not vitamin D supplements have a beneficial effect on bone density. This is an important issue for Australians as there is a high level of vitamin D deficiency even among healthy adults and children due to the success of sun safe campaigns. So having a good understanding of this issue is important for the health of many Australians.
The Blackmores Institute, which was set up to foster research and education into natural health for Health Care Professionals, had this to say on the issue:
A meta-analysis finding that vitamin D supplements have no beneficial effect on bone density has drawn intense criticism from experts who say the study has “serious limitations” and its conclusions could have “dire consequences” for public health for suggesting healthy adults don’t need to take vitamin D supplements.
According to a statement from United States’ peak body the Council for Responsible Nutrition (CRN) Vice President of Scientific and Regulatory Affairs, Duffy MacKay, N.D. “one of the serious limitations of this meta-analysis was the lack of consideration of studies that looked at how vitamin D and calcium work together.
“For populations that are most vulnerable to vitamin D deficiencies and insufficiencies – especially older adults – getting vitamin D from food alone is particularly challenging, and so supplementation may be warranted”.
A number of global public health and nutrition experts have also warned that the study, which was published this week in the Lancet, is being misinterpreted by mainstream, non-expert media outlets, who have reported the findings outside of their wider scientific context.
The principal organisation for natural nutrition and health in Australia, the Complementary Healthcare Council, agrees with the CRN, saying “this meta-analysis looks at the effects of vitamin D supplementation without co-administration of calcium on the effects of fracture prevention. This is a serious limitation as the scientific literature supports that vitamin D and calcium work together to provide a protective effect for helping to prevent osteoporosis.
“A further limitation is that the meta-analysis only looks at the effect of vitamin D supplementation on bone health. A large body of scientific literature shows that vitamin D plays an important role in other areas, such as cardiovascular health and immune health”.
“We shouldn’t be throwing the baby out with the bath water,” says Mr. Carl Gibson Chief Executive Officer of the CHC, “this study does not provide iron-clad evidence that healthy people should not be taking vitamin D supplements. Furthermore, while some people may regard themselves as healthy they still might not have optimal levels of vitamin D.
“The CHC advises that this meta-analysis should not discourage healthy people from taking vitamin D for all the possible benefits and should not discourage doctors and other healthcare practitioners to continue to test vitamin D levels,” Mr. Gibson says.
Vitamin D deficiency in Australia
In Australia, there is a high level of vitamin D deficiency even among healthy adults and children due to the success of the Slip Slop and Slap campaign against skin cancer.A position statement published in the Medical Journal of Australia in 2012 titled “Vitamin D and health in adults in Australia and New Zealand: a position statement” concurs with the Council for Responsible Nutrition statement that diet is not always a reliable way to get adequate vitamin D.
“Most adults are unlikely to obtain more than 5%–10% of their vitamin D requirement from dietary sources. The main source of vitamin D for people residing in Australia and New Zealand is exposure to sunlight,” the MJA papers states.
According to the authors of the position statement, led by Vitamin D expert, Professor Caryl A Nowson, from Deakin University in Melbourne, Vitamin D status has emerged as a significant public health issue in Australia and New Zealand.
“An estimated 31% of adults in Australia have inadequate vitamin D status, increasing to more than 50% in women during winter–spring and in people residing in southern states”.
The paper states:
- When sun exposure is minimal, vitamin D intake from dietary sources and supplementation of at least 600 IU (15 μg) per day for people aged ≤ 70 years and 800 IU (20 μg) per day for those aged > 70 years is recommended. People in high-risk groups may require higher doses.
- There is good evidence that vitamin D plus calcium supplementation effectively reduces fractures and falls in older men and women.
References available on request