Calcium assists heart function, but it can also cause problems when too much contributes to arterial plaque that clogs blood pathways. The balance is a subject of debate in the medical community, particularly in relation to calcium supplements, which may cause harm. Researchers are looking at the complex connection between calcium and the heart.
Calcium's Function in the Heart
Many chemicals and systems work synergistically with calcium to create the heartbeat. The sarcoplasmic reticulum, a membrane inside heart cells, holds calsequestrin, which stores and releases calcium rhythmically. The released calcium stimulates the heart-muscle contraction, or heartbeat.
Calcium Release and Arrhythmias
Some people lack calsequestrin, the chemical that holds calcium in the heart, because of their genetic code. According to research at Vanderbilt University, mice with heart muscles engineered to lack calsequestrin, released calcium sporadically rather than consistently, which created heart arrhythmias. Scientists believe the calsequestrin deficiency affects people the same way.
Heart Health and Calcium Supplements
Calcium functions as a heartbeat stimulator. But it can also interfere with optimal heart function because it can add plaque to arterial blockages that narrow or stop blood flow, a condition that causes heart attacks and cardiovascular weakness. A compilation of New Zealand studies blamed calcium supplements for a higher incidence of heart attacks. P.J. Skerritt, editor of the Harvard Health Letter, however, disagreed with the conclusion. Skerritt said that the percentage of heart patients who had taken the calcium was comparable to the percentage that had taken a placebo.
Calcium Food Sources
Improving the level of calcium in the blood supply with food may be safer until further studies determine the relationship between supplements and heart disease. Foods sources of calcium include rhubarb, collard greens, yogurt, enriched wheat flour, orange juice, ricotta cheese, milk, soybeans and spinach.
Testing
A coronary calcium scan can detect mineral deposits in the cardiovascular system. Heart arrhythmias may indicate that this test is necessary. Discuss the option and the role that calcium plays in your cardiovascular health with your doctor.
References
- University of Maryland Medical Center; Calcium Source; Linda Vorvick, M.D.; March 2009
- U.S. Department of Agriculture: National Nutrient Database for Standard Reference: Calcium
- Harvard Health Publications; Could Too Much Calcium Cause Heart Disease; P.J. Skerrett; August 2010
- Mayo Clinic; Heart Scan (Coronary Calcium Scan); November 2010
- Vanderbilt University; "Reporter"; Calcium Handling Key to Heart Rhythm: Study; Leigh MacMillan; September 2006
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