Here's the short version: Take calcium. Take calcium daily. Take calcium daily forever.
Now the long version.
Two long-term major studies of calcium use by women have appeared lately. One was an Australian study of 1,460 women older than 70, reported in the journal Archives of Internal Medicine. The other was a finding from the Women's Health Initiative (WHI), that major ongoing study of 36,000 postmenopausal women that has spawned so many articles and controversy over so many of its findings.
And the superficial, quick read version of both these studies is that calcium does nothing. No statistically significant benefits found.
This is true, and yet it is dead wrong. The superficial read is the wrong read. The headlines will steer you false yet again.
Dig deeper. Take a look at "Protecting Your Bones: New Evidence Helps Clarify the Benefits of Calcium," Tara Parker-Pope's Health Journal column in the April 25, 2006 Wall Street Journal. (Available online only to WSJ subscribers. Sorry.)
The real story is buried in the data, but it's a blockbuster. The reason the Australian study found no benefits is that 43% of the women in it stopped taking their calcium during the five year study. The women who kept taking the pills had a massive 34% reduction in their overall risk of a fracture.
About the same fraction of women stopped taking the calcium in the WHI study. And many of the women in the study were under 60, making them less likely to suffer fractures in the first place. Women over 60 were 21% less likely to suffer a hip fracture. Women who took the pills regularly had a 29% lower risk. When everyone was counted in, those who weren't taking calcium supplements before the study now had a 30% lower risk.
"It was a bit of a surprise and a bit disappointing to discover that the effect was so dependent on compliance," says [Australian] study author Richard L. Prince, associate professor at the School of Medicine and Pharmacology at the University of Western Australia. Patients need to make their calcium regimen a life-long habit "to get the full treatment effect."
As with every medication, side effects occur. The WHI study found that daily calcium may increase the, low, risk of kidney stones by 17%. However, the only side effect the Australian study spotted was constipation.
So take calcium now. Take it later. Take it daily. How much? 1200 mg is what the studies recommend.
And never get medical news just from headlines.