High-Calcium Diets Probably Cause Osteoporosis

At least every 5 years, the U.S. Depart­ment of Agri­cul­ture and the U.S. Depart­ment of Health and Human Ser­vices are required by fed­er­al law to issue Dietary Guide­lines for Amer­i­cans. Accord­ing to the law, these guide­lines are sup­posed to be based on the best avail­able sci­ence. Yet some of their rec­om­men­da­tions don’t seem to have any basis in sci­ence at all. In par­tic­u­lar, I think that their rec­om­men­da­tions about cal­ci­um intake will make the prob­lem of osteo­poro­sis worse, not bet­ter.
Con­tin­ue read­ing “High-Cal­ci­um Diets Prob­a­bly Cause Osteo­poro­sis”

Stop Worrying About Calcium Deficiency

The com­mit­tee that put togeth­er the Dietary Guide­lines for Amer­i­cans, 2010 were try­ing to solve a nonex­is­tent prob­lem: cal­ci­um defi­cien­cy. Unfor­tu­nate­ly, their sug­gest­ed solu­tion to this nonex­is­tent prob­lem would make some of our most seri­ous real prob­lems worse. If peo­ple fol­low these guide­lines and eat more dairy foods, they will actu­al­ly increase their risk for osteo­poro­sis and sev­er­al oth­er com­mon, seri­ous health prob­lems.

The human body is sur­pris­ing­ly good at main­tain­ing cal­ci­um bal­ance on a low-cal­ci­um diet. To find cas­es of true dietary defi­cien­cy of cal­ci­um, you have to look at peo­ple who were con­sum­ing extreme­ly abnor­mal diets. Most cas­es involved babies who were being fed some bizarre sub­sti­tute for breast milk. In real­i­ty, cas­es of rick­ets (soft bones) in chil­dren are near­ly always due to a short­age of vit­a­min D, the sun­shine vit­a­min.

When you think about it, most of the world’s large land ani­mals man­age to get enough cal­ci­um from their plant-based diet to grow an enor­mous skele­ton. Nor does any species oth­er than our own con­sume the milk of anoth­er species, or any milk at all after infan­cy. So why should we expect human beings to need dairy foods, or to need a cal­ci­um intake that can be achieved only through eat­ing dairy foods or tak­ing sup­ple­ments? It makes no sense.

Sci­en­tists have known for decades that osteo­poro­sis occurs main­ly in coun­tries where peo­ple eat a lot of dairy prod­ucts and have a rel­a­tive­ly high cal­ci­um intake. In fact, there’s rea­son to believe that eat­ing too much ani­mal pro­tein and too much cal­ci­um actu­al­ly caus­es osteo­poro­sis.

The pop­u­la­tions with a high risk for osteo­poro­sis also have high rates of death from coro­nary artery dis­ease. For­tu­nate­ly, the same kind of diet that pre­vents heart attacks also helps to keep the bones strong. That means eat­ing a low-fat, plant-based diet that includes plen­ty of fruits and veg­eta­bles.

It’s also impor­tant to get enough vit­a­min D. A few min­utes of expo­sure to mid­day sun on the face and arms dur­ing the spring, sum­mer, and fall should pro­vide enough vit­a­min D for most light-skinned peo­ple in the Unit­ed States. If you are dark-skinned, live in the far North, or have some oth­er rea­son why you can’t go out in the sun­shine, your doc­tor, physi­cian assis­tant, or nurse prac­ti­tion­er can mon­i­tor your vit­a­min D lev­els and advise you about vit­a­min D sup­ple­ments.

Calcium Supplements: More Heart Attacks, but Also More Osteoporosis

Women in the Unit­ed States are con­tin­u­al­ly pres­sured by their doc­tors and by the media to eat a high-cal­ci­um diet and take cal­ci­um sup­ple­ments, sup­pos­ed­ly to pre­vent osteo­poro­sis. I resist this advice, because I’ve known for more than 20 years that osteo­poro­sis is actu­al­ly most com­mon in the pop­u­la­tions with the high­est cal­ci­um intakes. Now, a study just pub­lished in the British Med­ical Jour­nal warns that cal­ci­um sup­ple­ments could also raise the risk of heart attack, which is the major cause of death in women in the Unit­ed States.

I found out about the link between high cal­ci­um intakes and osteo­poro­sis in the late 1980s, while I was edit­ing a hand­book for dieti­tians. The author wrote that osteo­poro­sis is com­mon only in soci­eties where peo­ple eat a lot of dairy prod­ucts. I was shocked by this infor­ma­tion. Lat­er on, I found that both the high pro­tein con­tent and the high cal­ci­um con­tent of dairy foods are impli­cat­ed in caus­ing osteo­poro­sis. For years, Har­vard pro­fes­sor Mark Heg­st­ed warned peo­ple that osteo­poro­sis was a result of the same kind of diet that caus­es heart dis­ease. He specif­i­cal­ly warned that high cal­ci­um intakes prob­a­bly make osteo­poro­sis worse. Sad­ly, his warn­ings fell on deaf ears.

Read­ing the arti­cle in the British Med­ical Jour­nal made me angry. The study it described was a meta-analy­sis, which means that it com­piled the results of sev­er­al clin­i­cal tri­als. The researchers found 15 clin­i­cal tri­als in which women were giv­en either cal­ci­um or place­bo, most­ly for the pre­ven­tion or treat­ment of osteo­poro­sis. What angered me was the dates of the stud­ies. The ear­li­est one was pub­lished in 1989, the lat­est in 2008. Even by the time the ear­li­est of those stud­ies was done, there was already plen­ty of rea­son to believe that cal­ci­um sup­ple­ments would have made the women’s osteo­poro­sis worse, not bet­ter. In oth­er words, human research sub­jects were sub­ject­ed to unnec­es­sary harm. That sort of thing is a huge vio­la­tion of med­ical research ethics. It’s also ille­gal in civ­i­lized coun­tries.

Med­ical researchers are sup­posed to do their home­work before they start enrolling human beings in a clin­i­cal tri­al. By the time that first study was done, it was already obvi­ous that high cal­ci­um intakes make osteo­poro­sis worse, not bet­ter. Har­vard pro­fes­sor Mark Heg­st­ed explained the prob­lem in an arti­cle pub­lished in 1986, before the first of the stud­ies includ­ed in the meta-analy­sis.

It’s bad enough that the aver­age doc­tor has had lit­tle to no train­ing in nutri­tion or dietet­ics. What’s even worse is that some of the doc­tors who are doing nutri­tion stud­ies evi­dent­ly don’t both­er to read the sci­en­tif­ic lit­er­a­ture on nutri­tion before they start exper­i­ment­ing on human beings.

Accord­ing to the arti­cle in the British Med­ical Jour­nal, there were 143 myocar­dial infarc­tions in the patients assigned to take cal­ci­um and 111 myocar­dial infarc­tions in the patients assigned to take a place­bo. If these women had been giv­en prop­er coun­sel­ing on how to make them­selves heart-attack-proof, all of these heart attacks could have been avoid­ed.

Pho­to by Ger­man Teno­rio