Vitamin D Can Help Elderly Women Survive

Giving vitamin D3 (cholecalciferol) to predominantly elderly women, mainly in institutional care, seems to increase survival. These women are likely to be vitamin D deficient with a significant risk of falls and fractures. This is the key conclusion in a systematic review published in the latest edition of The Cochrane Library.

Up until now there has been no clear view on whether there is a real benefit of taking vitamin D. “A Cochrane meta-analysis published only a couple of years ago found that there was some evidence for benefit, but it could not find an effect on mortality. We were, however, aware that more trials had been published and wanted to assess the effects of vitamin D when you added all the data together,” said Dr Goran Bjelakovic, who works at Department of Internal Medicine – Gastroenterology and Hepatology, at the University of Nis, in Serbia and at The Cochrane Hepato-Biliary Group at The Copenhagen Trial Unit in Copenhagen, Denmark.

The eight-strong international team of researchers identified 50 randomised trials that together had 94,148 participants. They had a mean age of 74 years, and 79% were women. “Our analyses suggest that vitamin D3 reduces mortality by about 6%. This means that you need to give about 200 people vitamin D3 for around two years to save one additional life,” says Bjelakovic.

There were no significant benefits of taking other forms of vitamin D such as vitamin D2, and the active forms of the vitamin, alfacalcidol or calcitriol. However, the researchers point out that they could only find much less data relating to these types of vitamin D and so these conclusions should be taken with caution. “We need to have more randomised trials that look specifically to see whether these forms of vitamin D do or don’t have benefits,” says Bjelakovic. His team did conclude that alfacalcidol and calcitriol significantly increased the risk of hypercalcaemia, and vitamin D3 combined with calcium significantly increased the risk of kidney stones.

There have been reports and comments that taking vitamin D can reduce the risk of getting cancer, but this work showed no evidence that vitamin D reduced cancer-related mortality.

“Previous reviews of preventive trials of vitamin D have not included as much information and have not examined the separate influence of different forms of vitamin D on mortality. By taking data from a larger number of trials we have been able to shed much more light on this important issue,” says Bjelakovic.

 

Vitamin D Supplements Found To Be Safe For Healthy Pregnant Women

Use of vitamin D supplements during pregnancy has long been a matter of concern but now researchers writing in theJournal of Bone and Mineral Research report that even a high supplementation amount in healthy pregnant women was safe and effective in raising circulating vitamin D to a level thought by some to be optimal. The study also found no adverse effects of vitamin D supplementation, even at the highest amount, in women or their newborns.

The research team, led by Dr. Bruce Hollis from the Medical University of South Carolina in Charleston, used a randomized controlled trial with healthy expectant mothers to discover how varying dosages of daily supplements could safely sustain a circulating vitamin D level of at least 32 nanograms per milliliter.

“Vitamin D supplementation during pregnancy remains controversial largely due to severe misconceptions about the potential harm it may cause to the fetus,” said Dr Hollis. “Surprisingly the scientific debate has made little progress since Dr. Gilbert Forbes made a recommendation of 200 IU (international units) per day in 1963, which was based on a hunch.”

While the threat of vitamin D during pregnancy has remained little known, it has been established that the vitamin plays a role in homeostasis, the body’s internal regulation, during pregnancy and that a deficiency can effect immune, pancreatic and cardiovascular systems.

Dr Hollis’ team monitored the pregnancies of 350 women, from a variety of ethnic and socio-economic backgrounds, who were all between 12 and 16 weeks into gestation. The women were randomly assigned to one of three groups. One group received 400 IU of vitamin D per day, the second group received 2,000 IU per day and the third received 4,000 IU daily.

The team found that women who received the highest level of supplementation (4,000 IU per day) were more likely to achieve and sustain the desired level of circulating levels of vitamin D throughout their pregnancy. Moreover, the researchers found that pregnant women who received lower levels of vitamin D supplementation did not attain the threshold circulating level of the vitamin.

“In our study subjects, a daily dosage of up to 4,000 IU of vitamin D was required to sustain normal metabolism in pregnant women,” concluded Dr Hollis. “Furthermore, following decades of speculation into its safety our research has demonstrated vitamin D supplementation to be both safe and effective.”

 

Full citation:
Hollis. B, Johnson. D, Hulsey. T, Ebeling. M, Wagner. L, “Vitamin D Supplementation during Pregnancy: Double Blind, Randomized Clinical Trial of Safety and Effectiveness”, Journal of Bone and Mineral Research, Wiley-Blackwell, June 2011: DOI