Vitamin D, Calcium: Ignore This News, Please

The Truth Squad has been awfully busy lately smacking down news stories that lead people to believe stuff that, for lack of a subtler term, ain't true.

A new report today from HealthDay is titled Vitamin D, Calcium Might Lower Breast Cancer Risk. To be fair--and the Truth Squad is rigorously fair--on the HealthDay site the story bears the key subhead, "But it's too early to recommend supplements, one expert says." On many sites, however, the subhead is suppressed.

Bottom line first
A study appearing in the Archives of Internal Medicine suggests a possible link--a possible association, not proof of cause-and-effect--between higher intake of Vitamin D and calcium and reduced breast cancer risk.

This study in 50 words or less
Researchers viewed self-reported dietary data from 30,000 women participating in Harvard's ongoing Women's Health Study. After 10 years, they found premenopausal women who got the most D and calcium had 30 percent fewer cases of breast cancer. Not so for postmenopausal women, however.

Yes, but. . .
The study didn't account for exposure to sunlight--a major source of vitamin D for people under 60 years old. At best this study shows an association, not cause and effect. Nobody involved with the study suggests women take D and/or calcium supplements to cut breast cancer risk.

So what are you going to do about it?
Nothing. Women near menopause often take calcium and vitamin D supplements for bone health. The evidence on that is pretty sketchy too. Worse: There's some evidence that high levels of D and calcium are linked to brain lesions in older people. Of course, that evidence is no more conclusive than today's report in Archives of Internal Medicine.

Wondering about best practices for breast cancer risk? I like this report on things you can and can't change to cut your risk from the American Cancer Society.

One more thing
This stuff is complicated.

Self-treating intuitively with supplements, or even diet, based on news headlines can result in more harm than help. Even if the study comes out of Harvard, follows a lot of people, and appears in a well-regarded peer-reviewed journal. The fact that a study is scientifically credible, and even important, has no bearing on whether it has implications for you.

So what are you going to do? Eat lots of different whole foods, and avoid eating much crap. Get exercise. Keep your brain busy. Love your family, or someone.

Everything else, for now, appears to be details.