Atherosclerosis, a buildup of cholesterol, calcium and other substances inside the artery walls, increases your risk of heart disease by blocking blood flow to the heart. While plaque, the substance that builds up in the artery, contains cholesterol, it also contains calcium. Researchers, such as South Beach Diet founder Dr. Arthur Agatston, feel that calcium buildup has a significant affect on increasing the risk of heart disease, while others feel excess calcium intake decreases atherosclerosis. Calcium doesn't raise cholesterol levels and may lower them, but study results are mixed.
Plaque Formation and Calcium
Calcium is part of the plaque that causes atherosclerosis, but how important its role is in heart disease is up for debate. Agatston feels it plays an essential role, more important than total cholesterol levels. He considers it as important as low-density lipoprotein levels, the so-called "bad" cholesterol that builds up in the arteries in atherosclerosis. An article initially published in the February 2004 issue of the "Harvard Men's Health Watch," on the other hand, states that calcium doesn't cause atherosclerosis, but occurs as part of the body's response to the inflammation and damage to the artery walls. Calcium comprises up to 20 percent of older, larger plaque deposits, according to the "Harvard Men's Health Watch" article.
Calcium and Cholesterol Studies
Studies show mixed results on the ways calcium intake affects cholesterol levels. A five-year follow-up study conducted by Albert Einstein College of Medicine, reported in the April 2010 "American Journal of Clinical Nutrition," analyzed results from the Women's Health Initiative Study. It found that supplementation with calcium and vitamin D did not significantly lower cholesterol levels in 1,259 postmenopausal women. However, a 12-month New Zealand study reported in the April 2002 "American Journal of Medicine," found a 7 percent increase in high-density lipoprotein, the "good" cholesterol, and a 6 percent decrease in LDL.
Coronary Calcium Imagining
Coronary calcium imagining, a technique devised by Dr. Agatston to visualize early calcium buildup inside the arteries, has proponents and detractors. Some say the technique has some value, but should not be a routine test for heart disease risk. The "Harvard Men's Health Watch" states that calcium buildup doesn't necessarily indicate the kind of plaque buildup that causes heart disease. This is because the type of plaque that ruptures and causes problems doesn't contain much calcium. Neither the American Heart Association nor the American College of Cardiology recommends routine use.
Considerations
The effects of calcium supplementation on cholesterol levels have yet to be conclusively determined. The effects of calcium buildup in the arteries and its role in atherosclerosis also have yet to be determined. Until well-designed large studies establish definite benefits or risks from calcium intake, follow your doctor's recommendation about calcium supplementation.
References
- CNN; Will You Have aHeart Attack? These Tests May Tell; David Martin; August 2011
- "Harvard Men's Health Watch":Counting coronary calcium: Are the New Scans Right for You?; Febrary 2004
- MayoClinic.com; Heart Scan (Coronary Calcium Scan); November 2010
- "American Journal of Medicine"; Effects of Calcium Supplementation on Serum Lipid Concentrations Older Women: A Randomized Controlled Trial; I. Reid, et al.; April 2002
- "American Journal of Clinical Nutrition"; Effect of 5 y of Calcium Plus Vitamin D Supplementation on Change in Circulating Lipids: Results From the Women's Health Initiative; S. Rajpathak, et al.; April 2010
