An apple a day keeps the orthopedist away

If I were to ask you how to pro­tect your­self from osteo­porosis, what would you say? Prob­ably some­thing like, “drink more milk,” or “take a cal­cium or vit­amin D sup­ple­ment,” right? I recently met with Katherine Tucker, pro­fessor of nutri­tional epi­demi­ology in the depart­ment of health sci­ences, and she said that while cal­cium and vit­amin D are impor­tant, they are just two of a whole host of impor­tant nutri­ents. How we get them is just as impor­tant (if not more impor­tant) as how much we get.

Osteo­porosis occurs as our bone min­eral den­sity dimin­ishes, said Tucker. Bone is not a static thing as many people think, but rather an active tissue that is con­stantly remod­eling itself — breaking down and building up. Over time, if our rate of bone break­down out­paces that of buildup, we have a problem. Bone min­eral den­sity is a strong pre­dictor for hip frac­ture among older adults, which is itself asso­ci­ated with 20 per­cent excess mor­tality. Fifty per­cent of hip frac­ture patients will never walk on their own again, Tucker told me, leading to immo­bi­liza­tion, reduced metab­o­lism, and gen­eral decline in health.

So, how can we avoid these serious con­cerns as we age? Turns out cal­cium pills alone likely won’t do the trick. Tucker’s epi­demi­o­log­ical analyses of data from sev­eral studies show that cal­cium and vit­amin D sup­ple­ments will help main­tain bone min­eral den­sity while we’re taking them, but as soon as we stop, we return to the same level of bone loss as we would if we’d never taken them. “Flooding the system helps,” she said. “But you must take it forever.”

Another common mis­con­cep­tion about bone health is its rela­tion to pro­tein. For a long time, doc­tors have asso­ci­ated high-​​protein diets with osteo­porosis because they saw high cal­cium con­cen­tra­tions in the urine of people given high doses of pro­tein in the lab­o­ra­tory. Tucker’s analyses with her col­leagues in the Fram­ingham Osteo­porosis Study  have shown that high pro­tein diets actu­ally lead to the least amount of bone loss in older adults. “This is why epi­demi­o­log­ical studies are so impor­tant,” said Tucker. “You have to do the research in free living pop­u­la­tions to see what’s really hap­pening.” Short term studies looked at the meta­bolic out­comes of high pro­tein diets, and inad­e­quately asso­ci­ated them with long term effects.

But pro­tein is acid-​​producing in the blood, said Tucker. This means we need other nutri­ents, like mag­ne­sium and potas­sium (which are buffers) to be main­tain a good acid/​base bal­ance. Unfor­tu­nately, more than half the pop­u­la­tion does not meet the rec­om­mended daily value for these. Tucker decided to take this knowl­edge and use it fur­ther studies, exploring whether people who did in fact have good magnesium/​potassium levels had stronger bones. Using the same pop­u­la­tion data, Tucker found that this was indeed the case.

And where do mag­ne­sium and potas­sium show up in the diet? Fruits and veg­eta­bles — those foods that Amer­i­cans are very poor at including in our diets. Tuckers’ was one of the first studies to show that fruits and veg­eta­bles are related to, and even crit­ical to, bone health. The mes­sage has been widely received by the research com­mu­nity, she said. But doc­tors and the gen­eral public are another story.

Turns out mod­erate alcohol con­sump­tion, par­tic­u­larly red wine, is also good for the bones, as it con­tains antiox­i­dants which min­i­mize oxida­tive stress and inhibit bone break­down. Eating  fruits and veg­eta­bles also con­tributes antiox­i­dants like carotenoids and vit­amin C,-which Tucker and her col­leagues have shown over the years to pro­tect bone min­eral den­sity and reduce risk of hip fracture.

Min­i­mizing your cola intake is another good idea if you’re on a bone health kick. Tthe problem here isn’t sugar, it’s phos­phoric acid. So even diet cola is a problem when it comes to bone den­sity. That’s because phos­phoric acid, which is used as a flavor addi­tive in colas (and Mt. Dew), dis­rupts the acid-​​base envi­ron­ment of the body without also intro­ducing the bal­ancing com­pounds nec­es­sary to pre­vent bone-​​breakdown, said Tucker.

I asked Tucker if osteo­porosis was more preva­lent in soci­eties that have diets low in fruits and veg­eta­bles. While she wasn’t willing to make a causative state­ment there, she did say that the United States and Northern Europe have the highest rates of hip frac­tures and that cul­tures that don’t even have dairy as a part of their diet tend to have the lowest rates of hip fractures.

Her team is now pur­suing studies around dairy intake with the same Fram­ingham Osteo­porosis Study data.