People take for granted that normal blood cholesterol levels will reduce their risk for heart attack and stroke. But even if your cholesterol falls within a healthy range, a high level of calcium in your blood can be dangerous. A new study, concluding that a coronary artery calcium scan, not a cholesterol test or stress test, is the most accurate way to assess heart disease risk, emphasizes the importance of controlling calcium intake.
Why calcium is important
Calcium is the most plentiful mineral in the human body. About 99 percent is stored in the skeleton, where it maintains healthy bones and teeth. But calcium is also essential for healthy muscles, blood vessels and nerves. Calcium is dissolved in the fluid inside and outside every cell in the body and too much or too little of the mineral can be deadly to those cells.
The body carefully controls blood calcium levels. But calcium is one of today’s most over-hyped nutrients. Older women are the primary target of the dairy industry and calcium supplement manufacturers, even though decreased kidney function and increased medication intake among older adults inhibits their body’s ability to shed excess calcium.
Why too much calcium is dangerous
Excess calcium is dangerous because healthy artery walls expand and contract as the heart pumps blood. With normal levels of calcium, the body stores the surplus in bones. But when a person ingests too much calcium, normally in the form of supplements, the excess overflows into the blood stream, where it stiffens blood vessel walls and binds with plaque to form clogged arteries.
Research supports the existence of this phenomenon. A 2010 study analyzed 11 published clinical trials that collected data on 12,000 people. Those taking calcium supplements had a 31 percent increased risk of a heart attack. The researchers concluded, “treatment of 1000 people with calcium for five years would cause an additional 14 myocardial infarctions [heart attacks], 10 strokes, and 13 deaths, and prevent 26 fractures.”
The coronary artery calcium scan
The medical community is adjusting accordingly. According to a study published last month in the Journal of the American Medical Association, coronary artery calcium scans are the most effective at predicting actual risk of heart attack or stroke.
A coronary artery scan involves taking a computed tomography scan—otherwise known as a “cat scan” of the heart. The images show how much calcium has built up in the arteries. Because artery calcification is part of the plaque build-up process, more calcium means more plaque. The higher the calcium score, the higher the risk for heart attack or stroke.
How to reduce coronary artery calcium
If you get a coronary artery scan with a high calcium score, diet is the best way to reduce the accumulation.
The Mediterranean diet is one of the best ways to condition your body to absorb, conserve and recycle calcium. It’s a menu rich in vitamins, minerals, fiber and plant-based, heart healthy fats and proteins. The Mediterranean diet is also heavy on green vegetables, which contain vitamin K2—a nutrient linked to decreased arterial calcification. Regular exercise has been shown to reduce arterial calcification.
A healthy diet makes calcium supplements unnecessary. Drinking milk is also unnecessary. Cows get the calcium in their milk from eating plants, and humans should get calcium the same way.