Take Calcium and Vitamin D
This is a companion piece to yesterday's blog about the value of Vitamin D in treating the aches and pains that often accompany the AIs. (If you haven't yet read it, the bottom line is that large doses of Vit D are often helpful, but speak with your doctor first). It turns out that the Sunshine Vitamin, as my mother used to call it, is useful in many ways. Taken with calcium, it is a powerful tool in our attempts to maintain strong bones.
And as an aside: this whole serious problem about bone health for women with breast cancer has really been a major and newish concern. It is a perfect example of the growing appreciation of the problems of survivorship. Back in the day, as they say, when there were very few treatments available and many more women died, none of this mattered too much. Now that so many women go on to live long and healthy lives, it matters a lot what the impact of their breast cancer treatments have been. Recent studies have suggested that bone loss is also a concern for pre-menopausal women who take tamoxifen, not just for post-menopausal women, especially those who are taking one of the AIs.
Having said that, here is a summary of a recent study that emphasizes the importance of taking Vit D along with the calcium. Note that the recommendation here is 1000 mg of calcium and 10 mgs of Vit D daily.
Calcium with Your Vitamin D Helps Stave Off Fractures
By Kristina Fiore, Staff Writer, MedPage Today
Reviewed by Zalman S. Agus, MD; Emeritus Professor
University of Pennsylvania School of Medicine.
January 12, 2010
Vitamin D alone won't reduce fracture risk, but scarfing it down with calcium will, researchers say.
Taking the nutrients together decreased overall fracture risk by 8%, and hip fracture risk by 16%, Bo Abrahamsen, MD, PhD, of Copenhagen University Hospital in Denmark, and colleagues reported online in BMJ.
"Calcium and vitamin D together are effective in reducing risk of all fractures and hip fractures, whereas we can't show anything like that for vitamin D on its own," Abrahamsen told MedPage Today.
Much previous research has focused on whether vitamin D can reduce fracture risk alone or in combination with calcium. Abrahamsen and colleagues used the raw data from many of those studies for their assessment.
They pooled data from seven randomized controlled trials, totaling 68,517 patients whose mean age was 69.9 years. Just under 15% were men.
They found that using vitamin D with calcium reduced both overall fracture risk (HR 0.92, 95% CI 0.86 to 0.99, P=0.025) and hip fracture risk (HR 0.84, 95% CI 0.70 to 1.01, P=0.07) compared with no treatment.
Vitamin D alone in daily doses of 10 mcg or 20 mcg had no significant effects on fracture risk, compared with placebo.
"The data all point toward the importance of giving calcium with your vitamin D," Abrahamsen said. "But we would very much welcome studies where larger doses of vitamin D were tried out on their own."
Until someone conducts higher-dose trials, he said, "We can't exclude that maybe vitamin D would be OK on its own if you took enough of it." "But in these relatively modest doses," he added, "we can only show an effect if you take calcium as well."
Whether calcium is more important in preventing fractures than was previously recognized remains to be determined, the researchers wrote.
Abrahamsen noted that the team did not compare vitamin D alone with vitamin D plus calcium head-to head.
They did, however, look for possible interactions between the nutrients and prior fractures, and found that the effects of calcium and vitamin D in combination were completely independent. "In this analysis, it doesn't seem to be important whether patients had prior fractures or not," Abrahamsen said. "It works equally well in patients with a prior fracture or patients taking calcium and vitamin D as primary prevention. . . . [This ] shows the fact that you had a prior fracture doesn't mean you won't benefit from calcium and vitamin D."
Since the results are consistent with three recent meta-analyses, Abrahamsen and colleagues recommend a dose of 10 mcg of vitamin D combined with 1,000 mg of calcium. In high-risk patients, they said this should be supplemented by bisphosphonates or other antiosteoporotic drugs.