Calcium Supplements: Should You Take Them?

Are calcium supplements helping or harming your health?

Calcium Supplements: Should You Take Them? | Johns Hopkins Medicine

Calcium is Canada’s go-to strategy for preventing bone loss and osteoporosis. It’s in dairy products, canned fish, beans, broccoli and kale.

It’s pumped into soy beverages, mixed into multivitamins and added to orange juice, breakfast cereals and energy bars.

Then there are the calcium supplements that many of us take, often on doctors’ orders, just to be safe. The more, the better, right?

Not quite. The safety of calcium supplements has become the subject of heated debate over the past 10 years, as researchers have produced evidence of side effects ranging from kidney stones to cardiovascular disease.

Earlier this month, a study linking calcium supplements to precancerous colon growths added another potential health risk to the list.

And while at least 40 per cent of Americans take calcium supplements, clinical trials have cast doubt on the effectiveness of these chalky tablets in preventing bone fractures.

So should Canadians ditch their calcium pills? No one disputes the importance of calcium for healthy bones. But the pros and cons of supplementary calcium may depend on your health status, the amount of supplementation – and which scientists you choose to believe.

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Dr. Mark Bolland, associate professor of medicine at the University of Auckland, was among the first to sound the alarm about calcium supplements, in a 2010 BMJ report linking them to an increased risk of heart attack.

Various studies have confirmed his findings, but others, including a 2016 review in the Annals of Internal Medicine, have shown no increased cardiovascular risk.

According to Bolland, these reassuring reports have either chosen to measure different cardiovascular outcomes, or “did not include all the data from all the studies.

” One explanation for this, he wrote in an email, involves “tight links between industry, academics and special societies in this area.”

Dr. Erin Michos, a cardiologist at Johns Hopkins Medicine, agrees. Michos and colleagues scanned the coronary arteries of 5,448 adults from different ethnic backgrounds to confirm they had no calcium deposits, in a study published in 2016 in Journal of the American Heart Association.

Ten years later, those who took calcium supplements had a 22-per-cent increased risk of developing calcification in their heart arteries, compared to non-supplement users. “We didn’t see this with dietary calcium,” she said, adding that supplements are “a billion-dollar industry.

Earlier this month, other researchers linked calcium supplements to serrated polyps, a less common type of colon growth that can become cancerous.

In a study published in the journal Gut, patients with a history of these polyps who took calcium supplements, with or without vitamin D, had a twofold increased risk of developing more of these growths within six to 10 years, compared to those who took no calcium supplements, or vitamin D alone.

The adverse effects of calcium supplements remain controversial, but so are the potential benefits.

In a 2006 study in the New England Journal of Medicine, women aged 50 to 79 who took a 1,000-mg calcium supplement with vitamin D had about the same hip fracture risk after seven years as those who took a placebo. Supplement users in this large clinical trial, involving 36,282 American women, showed just a 1-per-cent increase in hip-bone density – and more kidney stones.

On the flip side, a 2016 review in Osteoporosis International found that calcium supplementation plus vitamin D lowered the risk of total fractures by 15 per cent and hip fractures by 30 per cent.

This study came from the U.S.

National Osteoporosis Foundation, one of the organizations Bolland has described as “compromised” by the influence of companies that market supplements and nutrition-related laboratory tests.

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Calcium has made headlines since 1984, when the U.S. National Institutes of Health declared osteoporosis “a major public health problem.” Newspapers warned about osteoporosis, and the supplement industry stepped in to solve the nation’s “calcium deficiency.”

The theory that porous bones signalled a need for more calcium made sense, since calcium is the major mineral in bone, said Aileen Burford-Mason, a Toronto-based immunologist, cell biologist and author of Eat Well, Age Better. But, she added, “that story was wrong.

” Calcium is just part of the picture, since it is poorly absorbed without vitamin D, and requires vitamin K2 to help bind it to bone. Magnesium, too, plays a crucial role in bone health. In fact, “there is no essential nutrient that isn’t involved in keeping bones strong.

In 2010, Health Canada lowered its recommended dietary allowance of calcium to 1,000 mg a day for adults under age 51, 1,200 mg for men over 51 and 1,200 for all adults over 70.

The agency recommends vitamin D supplementation, and cautions that long-term intakes of calcium above 2,500 mg a day for adults under 51, and 2,000 mg for those over 51, “increase the risk of adverse health effects, such as kidney stones.”

Nevertheless, many physicians may be unaware of the current guidelines, said Dr. Angela Cheung, former chair of Osteoporosis Canada’s scientific advisory council and professor of medicine at the University of Toronto.

Back in 2001, when guidelines recommended a daily calcium intake of 1,000 to 1,500 mg for older adults, “a lot of physicians interpreted that as three [tablets] of 500 mg [per day],” she said, without considering the calcium patients were getting from food.

Since Canadian adults tend to be low on calcium, Cheung encourages people to increase their intake from dietary sources, if possible. Adults can start by tracking their current dietary intake using Osteoporosis Canada’s calcium calculator.

Calcium supplements can be useful for patients with specific health conditions, she added, but “for most people, I don’t think they need a supplement.”

Source: https://www.theglobeandmail.com/life/health-and-fitness/article-are-calcium-supplements-helping-or-harming-your-health/

Calcium supplements and your heart: Researchers send mixed messages

Calcium Supplements: Should You Take Them? | Johns Hopkins Medicine

Confused about calcium?

That wouldn’t be surprising. The mineral found in popular supplement pills — and in dairy foods, leafy greens and many fortified foods — is unquestionably good for your bones. But in recent years, doctors have raised concerns that calcium supplements might be over-used and bad for hearts.

Recently, two new studies made headlines. One found a link between the supplements and a build-up of calcium in arteries, a possible precursor to heart attacks and strokes.

A second, wider-ranging study found no heart risks and was the basis of new guidelines from two medical groups saying that calcium supplements should be considered heart safe.

“The public has been receiving very confusing and alarming messages about calcium supplements,” says JoAnn Manson, a professor of medicine at Harvard Medical School and chief of preventive medicine at Brigham and Women’s Hospital, Boston.

About 35% of U.S. adults take calcium supplements, alone or in multivitamins, according to a recent report in the medical journal JAMA.

So here’s what all those people need to know.

Concerns about heart risks may be fading.

Over the past decade, some studies have raised the possibility that calcium, from supplements but not from food, might raise heart risks.

Most recently, researchers at Johns Hopkins University tracked nearly 3,000 adults and found that those who took calcium supplements at the study outset were 22% more ly to show artery calcification 10 years later.

Those who got the most calcium from food had a decreased risk.

But the study, published in the Journal of the American Heart Association, was not designed in a way that could prove the supplements caused the artery changes.

And its findings were quickly refuted by a larger review of 31 previous studies, including some with more rigorous designs.

Taken together, those findings suggest healthy adults face no increased heart risks from calcium, in food or supplements, in amounts of up to 2,000-2,500 mg a day, researchers reported in the Annals of Internal Medicine.

 The review was funded by the non-profit National Osteoporosis Foundation, with support from Pfizer Consumer Healthcare, which makes calcium supplements.

“If you look at the overall totality of the evidence, there’s a lack of association between supplement use and heart attack and other cardiovascular events,” says Manson, who co-wrote an editorial accompanying the review.

The review “is really reassuring,” says Clifford Rosen, senior scientist at the Maine Medical Center Research Institute at the University of Maine. He was not involved in the research.

Also reassured: The osteoporosis foundation and the American Society for Preventive Cardiology, which issued new guidelines saying supplements appear heart safe.

Not everyone is convinced.

The larger review did not include all potentially relevant studies, says Erin Michos, an associate professor of medicine and epidemiology who led the Johns Hopkins study. “I’m still concerned about harm from supplements and I don’t advise them for my patients,” she says.

There are other reasons not to take calcium supplements.

The first is that most people don’t need them, Rosen says. Calcium intake from food has been rising, he says, with recent surveys finding averages around 1,000 mg a day — close to or meeting the 1,000 mg.

to 1,200 mg recommended for adults (the higher level is advised for women over 50 and men over 70).

 Many people get more than they realize, he says, not just from milk, cheese and yogurt, but from vegetables, grains, and, increasingly, fortified foods and beverages.

When there is a gap, food is a better choice than supplements, the experts agree. Calcium-rich foods, such as milk (300 mg a cup), plain yogurt (400 mg per cup) and kale (100 mg a cup), come with added nutritional benefits. And supplements come with extra risks: increases in kidney stones and, for some people, constipation and bloating.

A cup of milk has about 300 mg of calcium and is a better source than supplements, experts agree. (Photo: Stockbyte/Getty Images)

Some people do need supplements.

Older adults with osteoporosis — bone thinning severe enough to raise the risk of debilitating fractures — can benefit from calcium supplements, Rosen says, though most need just one 500 mg to 600 mg dose a day. Larger doses are poorly absorbed and rarely needed, he says.

Among others who might need a boost: Vegans, people with lactose intolerance and anyone who, for whatever reason, does not consume enough calcium, says Taylor Wallace, an affiliate professor of nutrition at George Mason University in Fairfax, Va., and a co-author of the new cardiovascular statement.

Teen girls, who are in crucial bone-building years, often have diets that fall short of their needs, 1,300 mg a day, Wallace says.

Your bones need more than calcium alone.

Vitamin D — found in fatty fish, fortified foods and supplements, and produced by the skin in response to sun exposure — also is essential to bone health.

Many supplements combine vitamin D and calcium, but experts disagree on who should take those supplements and in what doses. Under current U.S.

nutrition guidelines, teens and adults are advised to get 600 to 800 international units of vitamin D each day.

Also important for bone health: weight-bearing exercise, such as walking, dancing and workouts with weights.

Calcium and vitamin D are not enough. Weight-bearing exercise also is important for bone health. (Photo: Mike Kemp/Blend Images, Getty Images)

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Source: https://www.usatoday.com/story/life/2016/11/06/calcium-supplements-heart/93050736/

Calcium Supplements May Damage the Heart – 10/11/2016

Calcium Supplements: Should You Take Them? | Johns Hopkins Medicine

After analyzing 10 years of medical tests on more than 2,700 people in a federally funded heart disease study, researchers at Johns Hopkins Medicine and elsewhere conclude that taking calcium in the form of supplements may raise the risk of plaque buildup in arteries and heart damage, although a diet high in calcium-rich foods appears be protective.

In a report on the research, published Oct. 10 in the Journal of the American Heart Association, the researchers caution that their work only documents an association between calcium supplements and atherosclerosis, and does not prove cause and effect.

But they say the results add to growing scientific concerns about the potential harms of supplements, and they urge a consultation with a knowledgeable physician before using calcium supplements. An estimated 43 percent of American adult men and women take a supplement that includes calcium, according the National Institutes of Health.

“When it comes to using vitamin and mineral supplements, particularly calcium supplements being taken for bone health, many Americans think that more is always better,” says Erin Michos, M.D., M.H.S.

, associate director of preventive cardiology and associate professor of medicine at the Ciccarone Center for the Prevention of Heart Disease at the Johns Hopkins University School of Medicine.

“But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system.”

The researchers were motivated to look at the effects of calcium on the heart and vascular system because studies already showed that “ingested calcium supplements — particularly in older people — don’t make it to the skeleton or get completely excreted in the urine, so they must be accumulating in the body’s soft tissues,” says nutritionist John Anderson, Ph.D., professor emeritus of nutrition at the University of North Carolina at Chapel Hill’s Gillings School of Global Public Health and a co-author of the report. Scientists also knew that as a person ages, calcium-based plaque builds up in the body’s main blood vessel, the aorta and other arteries, impeding blood flow and increasing the risk of heart attack.

The investigators looked at detailed information from the Multi-Ethnic Study of Atherosclerosis, a long-running research project funded by the National Heart, Lung, and Blood Institute, which included more than 6,000 people seen at six research universities, including Johns Hopkins. Their study focused on 2,742 of these participants who completed dietary questionnaires and two CT scans spanning 10 years apart.

The participants chosen for this study ranged in age from 45 to 84, and 51 percent were female.  Forty-one percent were white, 26 percent were African-American, 22 percent were Hispanic and 12 percent were Chinese.

At the study’s onset in 2000, all participants answered a 120-part questionnaire about their dietary habits to determine how much calcium they took in by eating dairy products; leafy greens; calcium-enriched foods, cereals; and other calcium-rich foods.

Separately, the researchers inventoried what drugs and supplements each participant took on a daily basis. The investigators used cardiac CT scans to measure participants’ coronary artery calcium scores, a measure of calcification in the heart’s arteries and a marker of heart disease risk when the score is above zero.

Initially, 1,175 participants showed plaque in their heart arteries. The coronary artery calcium tests were repeated 10 years later to assess newly developing or worsening coronary heart disease.

For the analysis, the researchers first split the participants into five groups their total calcium intake, including both calcium supplements and dietary calcium.

After adjusting the data for age, sex, race, exercise, smoking, income, education, weight, smoking, drinking, blood pressure, blood sugar and family medical history, the researchers separated out 20 percent of participants with the highest total calcium intake, which was greater than 1,400 milligrams of calcium a day.

That group was found to be on average 27 percent less ly than the 20 percent of participants with the lowest calcium intake — less than 400 milligrams of daily calcium — to develop heart disease, as indicated by their coronary artery calcium test.

Next, the investigators focused on the differences among those taking in only dietary calcium and those using calcium supplements. Forty-six percent of their study population used calcium supplements.  

The researchers again accounted for the same demographic and lifestyle factors that could influence heart disease risk, as in the previous analysis, and found that supplement users showed a 22 percent increased lihood of having their coronary artery calcium scores rise higher than zero over the decade, indicating development of heart disease.

“There is clearly something different in how the body uses and responds to supplements versus intake through diet that makes it riskier,” says Anderson. “It could be that supplements contain calcium salts, or it could be from taking a large dose all at once that the body is unable to process.”

Among participants with highest dietary intake of calcium — over 1,022 milligrams per day — there was no increase in relative risk of developing heart disease over the 10-year study period.

“ this evidence, we can tell our patients that there doesn’t seem to be any harm in eating a heart-healthy diet that includes calcium-rich foods, and it may even be beneficial for the heart,” says Michos. “But patients should really discuss any plan to take calcium supplements with their doctor to sort out a proper dosage or whether they even need them.”

According to the U.S. Centers for Disease Control and Prevention, coronary heart disease kills over 370,000 people each year in the U.S. More than half of women over 60 take calcium supplements — many without the oversight of a physician — because they believe it will reduce their risk of osteoporosis.

Other authors on the study included Bridget Kruszka and Joseph Delaney of the University of Washington, Ka He of Indiana University, Gregory Burke of Wake Forest University, Alvaro Alonso of Emory University, Diane Bild of the Patient-Centered Outcomes Research Institute and Matthew Budoff of UCLA Medical Center.

The study was funded by contracts (N01-HC-95159, N01-HC-95160, N01-HC-95161, N01-HC-95162, N01-HC-95163, N01-HC-95164, N01-HC-95165, N01-HC-95167, N01-HC-95168 and N01-HC-95169); a grant (R21HL120394-01) from the National Heart, Lung, and Blood Institute; grants (UL1-TR-000040 and UL1-TR-001079) from the National Center for Research Resources; a grant (R01NS072243) from the National Institute of Neurological Disorders and Stroke; and the Blumenthal Scholars Award in Preventive Cardiology.

Source: https://www.hopkinsmedicine.org/news/media/releases/calcium_supplements_may_damage_the_heart

Calcium Supplements: Should You Take Them?

Calcium Supplements: Should You Take Them? | Johns Hopkins Medicine

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When you were a child, your mom may have encouraged you to drink milk tobuild strong bones. But as an adult, you’re much more ly to take acalcium supplement than down four glasses of milk a day to protect yourbone health.

However you do it, getting enough calcium is a good idea,since women are far more ly than men to developosteoporosis— a condition of weak and fragile bones that makes you prone to fractures:Of the 10 million Americans with osteoporosis, 80 percent are women.

But before you unwrap that chocolate-flavored calcium chew or swallow acalcium pill, you should know that taking calcium supplements may not behelping your bones at all. Even worse? The supplements may lead to majorhealth problems

It’s important to protect your bone strength and guard against fractures asyou age, but taking a supplement isn’t the best way to do that, saysErin Michos, MD, MHS, associate director of preventive cardiology for theCiccarone Center for the Prevention of Heart Disease.

“A nutrient in pill form is not processed in the body the same way as itis when ingested from a food source. Furthermore, people believe that theproof that calcium supplements fortify bones is more robust than it reallyis,” she says. “The truth is, the research is inconclusive.

But there is agrowing body of evidence that suggests no health benefit, or even worse,that calcium supplements may be harmful.”

Multiple studies have found that there’s little to no benefit to takingcalcium supplements for the prevention of hip fractures.

On the other hand,recent studies have linked calcium supplements with an increased risk ofcolon polyps (small growths in the large intestine that can becomecancerous) and kidney stones, which are hard masses usually formed in thekidneys from an accumulation of calcium and other substances. Additionally,a2016 study by Michosand her colleagues suggested that calcium supplements may increase the riskof calcium buildup in the heart’s arteries.

“I’m very concerned about the potential for calcium supplements tocontribute to heart attacks and heart disease,” says Michos. “The bodycan’t process more than 500 milligrams of calcium at a time.

If you take asupplement with more than that, your body has to do something with theexcess.

It’s possible that higher calcium levels in the blood could triggerblood clots or that calcium could be deposited along artery walls, whichwould contribute to the narrowing of blood vessels.”

A Better Calcium Option

While taking calcium supplements may produce unwanted side effects, meetingyour calcium needs through your diet is safe. “When you get calcium throughyour diet, you’re taking it in small amounts spread throughout the dayalong with other food sources, which helps you absorb the nutrient,”explains Michos. “Most people can get adequate calcium through their dietif they make an effort.”

Women ages 19 to 50 should consume 1,000 milligrams of calcium a day, andthe target for women over 50 is 1,200 milligrams per day. Good dietarysources of calcium include:

  • Almonds
  • Oranges
  • Dried figs
  • Soybeans
  • Garbanzo, white and pinto beans
  • Low-fat dairy such as milk and yogurt
  • Leafy green vegetables such as kale and spinach

Exercise to Strengthen Bones

Being active and exercising on a regular basis protects bone health.Weight-bearing exercises such as walking, jogging and weight training areespecially helpful in preventing bone loss.

Simply moving more throughout the day supports bone health, too.

Researchindicates that women who sit for more than nine hours a day are 50 percentmore ly to have a hip fracture than those who are less sedentary.

Finding ways to work more walking or standing into your day can add up. Forexample, park farther away from buildings, take the stairs instead of theelevator and pace while on phone calls.

For most women, skipping calcium supplements in favor of boosting dietarycalcium and focusing on weight-bearing exercise is the best way to keepbones strong. But if you’re still concerned about getting enough calcium,talk to your doctor first before taking supplements to see if you reallyneed them.

Source: https://www.hopkinsmedicine.org/health/wellness-and-prevention/calcium-supplements-should-you-take-them

If you take calcium supplements, new study shows why you may need to stop

Calcium Supplements: Should You Take Them? | Johns Hopkins Medicine

A new study adds to evidence that calcium supplements — but not calcium from food — might be bad for your heart.

At the same time, a second study shows Americans still have faith in their supplements. About half take supplements of some sort, despite dozens of studies showing they do not help most healthy people at all and can often be harmful.

Calcium supplements could lead to plaque buildup in arteries

Oct. 12, 201600:28

The new research builds an even stronger case against calcium pills.

People who took calcium pills were about 22 percent more ly to develop dangerous buildups called plaque in their arteries than people who did not take them, the new study showed.

But people who also ate a lot of calcium in food seemed to be protected, the team at Johns Hopkins University found.

“ this evidence, we can tell our patients that there doesn’t seem to be any harm in eating a heart-healthy diet that includes calcium-rich foods, and it may even be beneficial for the heart,” Dr. Erin Michos, an expert in heart disease prevention who helped lead the study, said in a statement.

RELATED: Study finds calcium pills don't help your bones

“But patients should really discuss any plan to take calcium supplements with their doctor to sort out a proper dosage or whether they even need them.”

The findings, published Tuesday in the Journal of the American Heart Association, backs up what experts already know about calcium supplements. Other studies have also shown the pills might not strengthen bones and might just send calcium straight to the blood vessels instead.

Should you take vitamin supplements?

May 20, 201501:38

It’s not clear why.

“There is clearly something different in how the body uses and responds to supplements versus intake through diet that makes it riskier,” said John Anderson, a nutrition professor at the University of North Carolina at Chapel Hill who worked on the study.

“It could be that supplements contain calcium salts, or it could be from taking a large dose all at once that the body is unable to process.”

For the study, the team looked at 2,700 people taking part in a larger survey. They had filled out questionnaires in 2000 and got CT scans — a type of souped-up x-ray — in 2000 and again in 2010.

These CT scans can show whether calcium-heavy deposits are building up in the arteries.

Those who ate more than 1,400 milligrams of calcium a day were 27 percent less ly to have this buildup than the others, the team found.

RELATED: Supplements send thousands to ER every year

But when they looked at the source of calcium, they found those who took supplements were more ly to develop the blockages.

The Council for Responsible Nutrition, a lobby group for the supplement industry, said in a statement that the findings showed calcium supplements are safe. It did not explain why it came to that conclusion.

Is There Any Proof Calcium Supplements Work?

Sept. 29, 201502:13

Federal data show that about half of Americans take calcium supplements.

In 2012, the U.S. Preventive Services Task Force issued new recommendations saying there's not enough evidence to support the use of calcium or vitamin D supplements, and recommending against it in some cases.

Women over 50 are advised to get 1,200 mg of calcium a day and women under 50 are advised to get 1,000 mg a day. Men are advised to get 1,000 mg a day although men over 70 are supposed to get 1,200 mg.

Dairy products are rich in calcium but so are leafy green vegetables, fortified milks such as soymilk and some juices and breakfast cereals.

RELATED: Some supplements might fuel cancer

Another study released Tuesday in the Journal of the American Medical Association showed that just over 50 percent of Americans take vitamins or supplements of some sort.

Most are doing it on their own, Elizabeth Kantor of Memorial Sloan Kettering Cancer Center in New York, and colleagues found.

“Although often used with an intention of improving or maintaining health, it was estimated that in 2007- 2010 only 23 percent of all supplement products were used at the recommendation of a health care provider,” they wrote.

“Why would consumers continue to use supplements after high-quality trials found many of these products to be no more effective than placebos?” Dr. Pieter Cohen of Harvard Medical School asked in a commentary.

“One factor may simply be that consumers are not aware of these negative results, and so continue to use the products they have been using for years,” he said.

But some may not believe medical science, while others may be swayed by the heavy advertising of the $32 billion supplement industry, which is only lightly regulated, Cohen said.

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Source: https://www.today.com/health/calcium-supplements-might-hurt-your-heart-study-finds-t103811

Calcium supplements may damage the heart

Calcium Supplements: Should You Take Them? | Johns Hopkins Medicine

After analyzing 10 years of medical tests on more than 2,700 people in a federally funded heart disease study, researchers at Johns Hopkins Medicine and elsewhere conclude that taking calcium in the form of supplements may raise the risk of plaque buildup in arteries and heart damage, although a diet high in calcium-rich foods appears be protective.

In a report on the research, published Oct. 10 in the Journal of the American Heart Association, the researchers caution that their work only documents an association between calcium supplements and atherosclerosis, and does not prove cause and effect.

But they say the results add to growing scientific concerns about the potential harms of supplements, and they urge a consultation with a knowledgeable physician before using calcium supplements. An estimated 43 percent of American adult men and women take a supplement that includes calcium, according the National Institutes of Health.

“When it comes to using vitamin and mineral supplements, particularly calcium supplements being taken for bone health, many Americans think that more is always better,” says Erin Michos, M.D., M.H.S.

, associate director of preventive cardiology and associate professor of medicine at the Ciccarone Center for the Prevention of Heart Disease at the Johns Hopkins University School of Medicine.

“But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system.”

The researchers were motivated to look at the effects of calcium on the heart and vascular system because studies already showed that “ingested calcium supplements — particularly in older people — don't make it to the skeleton or get completely excreted in the urine, so they must be accumulating in the body's soft tissues,” says nutritionist John Anderson, Ph.D., professor emeritus of nutrition at the University of North Carolina at Chapel Hill's Gillings School of Global Public Health and a co-author of the report. Scientists also knew that as a person ages, calcium-based plaque builds up in the body's main blood vessel, the aorta and other arteries, impeding blood flow and increasing the risk of heart attack.

The investigators looked at detailed information from the Multi-Ethnic Study of Atherosclerosis, a long-running research project funded by the National Heart, Lung, and Blood Institute, which included more than 6,000 people seen at six research universities, including Johns Hopkins. Their study focused on 2,742 of these participants who completed dietary questionnaires and two CT scans spanning 10 years apart.

The participants chosen for this study ranged in age from 45 to 84, and 51 percent were female. Forty-one percent were white, 26 percent were African-American, 22 percent were Hispanic and 12 percent were Chinese.

At the study's onset in 2000, all participants answered a 120-part questionnaire about their dietary habits to determine how much calcium they took in by eating dairy products; leafy greens; calcium-enriched foods, cereals; and other calcium-rich foods.

Separately, the researchers inventoried what drugs and supplements each participant took on a daily basis. The investigators used cardiac CT scans to measure participants' coronary artery calcium scores, a measure of calcification in the heart's arteries and a marker of heart disease risk when the score is above zero.

Initially, 1,175 participants showed plaque in their heart arteries. The coronary artery calcium tests were repeated 10 years later to assess newly developing or worsening coronary heart disease.

For the analysis, the researchers first split the participants into five groups their total calcium intake, including both calcium supplements and dietary calcium.

After adjusting the data for age, sex, race, exercise, smoking, income, education, weight, smoking, drinking, blood pressure, blood sugar and family medical history, the researchers separated out 20 percent of participants with the highest total calcium intake, which was greater than 1,400 milligrams of calcium a day.

That group was found to be on average 27 percent less ly than the 20 percent of participants with the lowest calcium intake — less than 400 milligrams of daily calcium — to develop heart disease, as indicated by their coronary artery calcium test.

Next, the investigators focused on the differences among those taking in only dietary calcium and those using calcium supplements. Forty-six percent of their study population used calcium supplements.

The researchers again accounted for the same demographic and lifestyle factors that could influence heart disease risk, as in the previous analysis, and found that supplement users showed a 22 percent increased lihood of having their coronary artery calcium scores rise higher than zero over the decade, indicating development of heart disease.

“There is clearly something different in how the body uses and responds to supplements versus intake through diet that makes it riskier,” says Anderson. “It could be that supplements contain calcium salts, or it could be from taking a large dose all at once that the body is unable to process.”

Among participants with highest dietary intake of calcium — over 1,022 milligrams per day — there was no increase in relative risk of developing heart disease over the 10-year study period.

” this evidence, we can tell our patients that there doesn't seem to be any harm in eating a heart-healthy diet that includes calcium-rich foods, and it may even be beneficial for the heart,” says Michos. “But patients should really discuss any plan to take calcium supplements with their doctor to sort out a proper dosage or whether they even need them.”

According to the U.S. Centers for Disease Control and Prevention, coronary heart disease kills over 370,000 people each year in the U.S. More than half of women over 60 take calcium supplements — many without the oversight of a physician — because they believe it will reduce their risk of osteoporosis.

Story Source:

Materials provided by Johns Hopkins Medicine. Note: Content may be edited for style and length.

Source: https://www.sciencedaily.com/releases/2016/10/161011182621.htm