Study Shows Limited Benefits From Calcium

Associated Press ^ | 2-15-06 | JEFF DONN

[Pharmboy]

The biggest study ever of calcium and vitamin D supplements for older women showed they offered only limited protection against broken bones, raising questions over what has been an article of faith among doctors and nutritionists.

The supplements seemed to reduce the risk of broken hips in women over 60 and also helped those who took the supplements most regularly. But as to preventing bone fractures overall, vitamin D and calcium flunked in these healthy women.

One of the researchers, Dr. Norman Lasser at New Jersey Medical School, said the study is "not as ringing an endorsement of calcium as one might like."

Even so, many experts said they would stand behind federal guidelines recommending the supplements, if needed, to meet standard intake of calcium and vitamin D.

"There's probably a small benefit," said Dr. Joel Finkelstein, of Massachusetts General Hospital, who wrote an editorial in the New England Journal of Medicine where the study appeared Thursday. "It's a good start, but women at higher risk need to know it's not enough."

The findings were an offshoot of the big national study of diet and hormone therapy known as the Women's Health Initiative.

Osteoporosis touches an estimated 10 million Americans, making their bones prone to break. One of two women will suffer such a fracture in her lifetime.

For women over age 50, federal guidelines recommend 1,200 milligrams of bone-building calcium and 400-600 international units of vitamin D daily from diet and, if needed, supplements.

The seven-year study of 36,282 women ages 50 to 79 gave half the participants 1,000 milligrams of calcium and 400 units of vitamin D, while the other half took dummy pills.

However, many were also taking their own supplements before the research began, and they were allowed to keep doing so, whether they were assigned to the test group or the comparison group. These extra supplements may have helped the women stay healthy but ironically diluted the findings, since any benefit is harder to show against a backdrop of fewer fractures. Also, women in the study were taking hormone pills, likely further cutting the number of fractures.

The study showed better hip bone density in the group given supplements, but they ranked no better statistically in avoiding fractures of all kinds. However, women over age 60 reduced their chances of hip fracture by 21 percent with the supplements.

Many women sometimes missed their daily dose — a common phenomenon in real-world testing — but those who took their supplements most faithfully lowered their risk by 29 percent.

"We still do believe ... that maintaining an adequate calcium intake will lay the foundation for bone health," said lead author Dr. Rebecca Jackson at Ohio State University.

Dr. Bess Dawson-Hughes, a Tufts University vitamin expert who helped shape the dietary guidelines, said they should remain unchanged for now. She largely dismissed the overall negative finding.

"You put people who don't need it together with people who aren't taking it, and you find nothing — and that really isn't all that surprising," she said.

Some researchers said the effect would have been clearer with higher doses of vitamin D, perhaps up to 1,000 units daily. The vitamin helps the body absorb calcium and promotes muscle health, reducing falls.

"We don't want to send the message to people to throw away their calcium pills, which was my wife's first reaction," said Lasser, one of the study authors.

The study did show a significant side effect with the diet supplements: a 17 percent increase in the risk of kidney stones. But several doctors downplayed that risk, saying hip fractures are typically much worse than kidney stones.

Doctors said the study suggests that women at higher risk of fracture — whose tests show lost bone density — likely need more than diet supplements. They may require osteoporosis drugs.

The study also checked whether the supplements might help prevent colon cancer, and the results indicated there was no benefit. That wasn't a big surprise partly because past studies had not signaled much benefit.

Still, the researchers plan to check participants in future years, because colorectal cancer can take 10 to 20 years to develop.

___

On the Net:

New England Journal of Medicine: http://nejm.org

federal dietary guidelines:

http://www.health.gov/dietaryguidelines/dga2005/document/html/chapter2.htm

Osteoporosis facts:

http://www.osteo.org/newfile.asp?docfast&doctitleFast+Facts+on+Osteoporosi

&doctypeHTML

[Balata]

"Calcium IS overrated...."

Well, I don't think calcium is overrated, but I do think it is very much misunderstood. There are many factors that are important for its absorption along with a complicated regulatory mechanism in the body.

[Hoodlum91]

Activity is important.

As is no crash dieting in teens and twenties. that's when women build most of their bone. Unfortunately, it's also when girls are most susceptible to body image. Which is why many of my 30 something friends are already having osteoporosis issues.

[alieno nomine]

"recruited 36,282 postmenopausal women, 50 to 79 years of age"

Bone health is a life long event. The process of maintaining good bone health means living a healthy lifestyle and eating the "right" foods with good balance of vitamins and minerals. Supplementing Calcium after menopause will probably have little benefit at that late stage, but a good calcium diet throughout life will probably be more likely to preserve bone later in life, or slow the process of degeneration.

[alieno nomine]

Also this:

Nutritional modulators of bone remodeling during aging

Gregory R Mundy

From the University of Texas Health Science Center at San Antonio, Texas

ABSTRACT

Bone mass declines progressively with age in both men and women from the age of {approx}30 y. Increased longevity will inevitability be associated with an increase in the incidence of osteoporosis, its associated complications, and incurred health care costs. Current pharmacologic approaches focus on inhibiting bone resorption in those with osteoporosis but do little to improve bone mass. Increased understanding of the cellular events responsible for normal bone formation has led to multiple pathways that can be targeted to positively influence bone mass. Bone morphogenetic proteins (BMPs) have been shown to stimulate bone formation, and the BMP2 gene was recently linked to osteoporosis. BMP-2 therefore represents one potential molecular target to identify new agents to simulate bone formation. Research is accumulating on the positive effects of dietary sources that stimulate the BMP2 promoter and their effects on bone formation. Flavonoids and statins occur naturally in food products and have been shown to promote bone formation. It may be possible to influence peak bone mass by dietary means and to decrease the risk of osteoporosis in later life. To ease the future burden of osteoporosis, focusing on prevention will be key, and this could include dietary interventions to stimulate bone formation.

Mundy, pp. 427S-430S.

American Journal of Clinical Nutrition, Vol. 83, No. 2, 427S-430S, February 2006 © 2006 American Society for Clinical Nutrition

[angelanddevil2]

In in my 30's and I don't have osteoporosis, that I am aware of. Ever since I remember I drink about 1 liter of milk a day (chocolate milk to be exact). Not as glamorous as wine, right. And there is a lot of fat in milk too. I just changed to the 2% kind. Disgusting!. I will have to get used to it. I hope the chicken breast I am about to eat has either calcium or vitamine D.

[alieno nomine]

and this:

Starting down the right path: nutrition connections with chronic diseases of later life

Johanna Dwyer From the Friedman School of Nutrition Science and Policy and School of Medicine; the Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University; and the Frances Stern Nutrition Center, Tufts–New England Medical Center, Boston, MA

ABSTRACT

Thirty years have been added to the average life expectancy of Americans over the past century. It is a reasonable expectation that Americans will achieve an average life span of ≥100 y within this century. The most dramatic decreases in early-life and midlife mortality coincided with advances in medicine; curative medicine has played a lesser role. The aging of the population alone has already increased health care costs, and as we move toward even longer lives, these costs will likely increase even more. Therefore, establishing and safeguarding optimal health from early life must become increasingly important concerns for governments and health care providers if they are to allocate resources wisely and ensure and maintain a high quality of life in the population. A prevention-oriented, life cycle approach is critical to establishing and maintaining health throughout life. This approach can delay and compress morbidity and the social toll associated with chronic disease and disability for as long as possible into old age. Good evidence exists that early nutrition affects key risk factors for chronic degenerative diseases of middle and later life, such as osteoporosis and cardiovascular disease. The influence of nutrition on health status and morbidity supports primary, secondary, and tertiary prevention of disease and intervention strategies at each point in the process. The objective of such a prevention-oriented model is to enable people to live well for longer, while minimizing chronic disability. Starting down the right path with appropriate nutrition and staying on it by eating well are important components of healthy aging.

Dwyer, pp. 415S-420S.

American Journal of Clinical Nutrition, Vol. 83, No. 2, 415S-420S, February 2006 © 2006 American Society for Clinical Nutrition

[Balata]

Calcium also has many functions in the body. It not only initiates muscle contraction but also helps to maintain proper heart function, nerve transmission, and blood clotting.

[japaneseghost]

Why calcium and vitamin D? Everything I've read says that one must take half the amount of magnesium with calcium, or the calcium won't get absorbed, and that calcium must be in liquid or liquid-gel form, or it just passes through the intestines unabsorbed.

[Hoodlum91]

That's the key. I'm the same way...lots of milk my entire life. Now I'm one of the few in my group who isn't having issues. The worst ones are the ones who either didn't drink milk in their late teens and twenties or did low fat diets in that time. They're now a mess.

[goodnesswins]

Ha....tell my Daughter-in-law that, would ya? Please...

[goodnesswins]

Just curious....How are "they a mess?" From what I see of the younger generation, there are two camps....the junk/fast food ones, and the more healthy food ones....comments?

[alieno nomine]

and for something way over my head:

JA Clowes, BL Riggs, and S Khosla

The role of the immune system in the pathophysiology of osteoporosis.

Immunol Rev 2005;208(): 207-27

The role of the immune system in the development of senile osteoporosis, which arises primarily through the effects of estrogen deficiency and secondary hyperparathyroidism, is slowly being unraveled. This review focuses on our current understanding of how the components of this complex-interlinked system are regulated and how these fit with previous models of senile and postmenopausal osteoporosis. There is certainly substantial evidence that bone remodeling is a tightly regulated, finely balanced process influenced by subtle changes in proinflammatory and inhibitory cytokines as well as hormones and cellular components that act primarily but not exclusively through the receptor activator of nuclear factor-kappaB (RANK)/RANK ligand/osteoprotegerin system. In addition, an acute or chronic imbalance in the system due to infection or inflammation could contribute to systemic (or local) bone loss and increase the risk of fracture. Although significant progress has been made, there remains much to be done in unraveling this complex interaction between the immune system and bone.

Mayo Clinic College of Medicine, Endocrine Research Unit, St Mary's Hospital, Rochester, MN 55905, USA.

clowes.jackie@mayo.edu

[Balata]

"This pertained to the upregulation of whatever enzymatic pathway builds or removes bone structure... Put another way, the skeleton represents a large reserve of calcium, and keeping blood concentration precisely balanced is a strong priority over how much the bones get to keep for themselves."

This is true, but what many people don't understand is that in the biochemistry of the body, enzymes are used over and over where Vitamins are "burned" or used up in the chemical equation, thus needing to be replaced. And the replacing of the vitamin, in this case Calcium, is where the questions arise.

[tiki]

Osteoporosis runs in my husbands family. My husband has overindulged in calcium all his life and is strong as an ox is large boned and very active and he has it. I, on the other hand have weighed 100 lbs most of my life, don't drink milk or take calcium and am small boned and I don't have any problem. Its in the genes.

[djf]

I think I've also heard that to metabolize calcium into bone, you also need magnesium and phosphorous, thats why most of the supplements have all three.

[neverdem]

thanx, bfl

[neverdem]

A prior doctor told me not to take multivitamins, unless I could find one without calcium in it, which is almost impossible.

I have no problem finding multivitamins without any minerals. Go find a large chain drug store, and ask for help if you have trouble finding plain multivitamins.

[goodnesswins]

"It's in the genes." Or...maybe HORMONES??? Or the amount of vegetables eaten, i.e. the balance between protein and vitamins and minerals. I also wonder if certain populations are more at risk....i.e. Finnish vs. Germans ancestry? Lots of questions...LOL.

[LZ_Bayonet]

"...the body goes to where it is stored (bones) and pulls it out and takes it through the muscles to use which eventually leads to a demineralization of the bones..."

Finally!! Now I understand how the poultry industry produces "boneless chicken". Those chicken sheds I see on farms are apparently just big PowerHouse gyms for chickens. When they fall down, they're ready to ship. Calcium-free environment too I'll bet - no wonder you never see a sign over the driveway with the farmer's name that says, "Chicken AND Dairy Farm".
BTW - Are "Boneless Chicken Patties" imported from Ireland? (Kinda weird that they could give some of them a good old Irish name and then end up slitting their throat.)

[Pharmboy]

Yes you did mention the parathyroids...my error.