Do Vegans Have Weak Bones?
Today, BMC Medicine published a new study on veganism and bone health – the latest addition to more than 1,200 already published on the subject.
Reading some of the headlines this new research has inspired, I’m reminded of a quote from the book Building Bone Vitality. I included it in a blog post from early August:
“The news media report what’s new. Nothing wrong with that. One week the latest study shows that beer causes cancer, coffee causes heart disease, and whatever. The next week, the next study shows the opposite. Over time, instead of becoming informed, the public becomes chronically confused.”
The book’s authors, nutrition professor Amy Joy Lanou Ph.D. and medical journalist Michael Castleman, continued: “No single study is ever definitive. What counts is the weight of the evidence across all trials.”
Underlying this statement was Dr. Lanou’s extensive personal research into bone health studies. She found that about one-third seemed to support the idea of animal-based calcium, decreasing bone-fracture risk.
However, two-thirds reached the opposite conclusion – and they included larger numbers of participants and more randomized, double-blind controlled trials.
Those findings allowed her to set aside the studies supporting animal-based calcium in favor of those opposing it.
But – where the latest bone-fracture study is concerned – even Dr. Lanou’s work couldn’t stop headlines such as:
43 percent more likely to suffer bone fractures, study shows. (New York Post)
Vegans may be at higher risk for bone fractures, study finds. (CNN)
Vegan Diets Tied to Higher Bone Fracture Risk. (US News)
The Oxford research behind those headlines analyzed partial data from the earlier landmark EPIC-Oxford study. And on further examination, their conclusions raise more questions than they answer.
During today’s Exam Room podcast, Dr. Neal Barnard addressed some of those questions. He began by acknowledging that EPIC-Oxford’s nearly 2,000 vegans did have a higher bone fracture rate than its nearly 30,000 meat-eaters.
The question is, “Why?” Starting at minute 5:06, Dr. Barnard proceeds with some exceptionally sensible answers:
The meat-eaters were much more likely to be overweight or obese – essentially giving them a “cushioning effect!”
“If you’ve got a lot of body weight and you fall down, you are much less likely to break a hip. If you’re at a healthy weight and you fall down, you are more likely to break a hip.”
“Body fat also makes estrogens – and that can have an effect on bone integrity.”
“Some people in the vegan group were the non-vegetable eating ones – and not getting that much calcium.”
“In this study, the vegans were substantially more physically active – more likely to break a bone.”
His conclusion? Every vegan can get adequate calcium by eating plenty of beans and greens, including:
It’s too bad the Oxford researchers didn’t separate the vegans into those who were eating completely whole-food, plant-based, and those who were “non-vegetable eating.” Their findings might have told a very different story!
Until someone does that, however, I’ll put my faith in Dr. Lanou’s approach. And the majority of the evidence points to plant-based food being best for bone vitality.