Calcium Supplements May Damage the Heart – Experts Recommend Caution Before Taking Calcium Supplements – John Hopkins
I have been cautioning my patients for years against taking the RDA of Calcium in supplement form. Now John Hopkins has cited very large studies that conclude that the total daily calcium intake, meaning the amount from both your food supplement intake, as well as the source of your calcium, i.e. food or supplement is crucial to preventing an increase risk of heart and vascular problems. I am including the entire article here for you to read, as well as the link below.
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.
“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, like 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.