It’s widely known that milk is rich in calcium, which is good for bone health and preventing osteoporosis, or thinning of the bones.
While calcium is an element that is essential for living organisms, including humans, it also plays a factor in atherosclerosis, or hardening of the arteries, which is the leading cause of heart attacks, stroke, and peripheral artery disease.
So what’s the difference between the calcium we put into our bodies to nourish them and the calcium our bodies manufacture as part of the disease process?
Good Calcium
More than 99 percent of body calcium is stored in the bones and teeth. This “good” calcium, in combination with Vitamin D, is essential for proper bone mass, helping prevent osteoporosis.
It can be obtained from low-fat dairy products, combined with a diet high in fruits and vegetables. It helps keep blood pressure in check, and this helps decrease blood cholesterol. It also helps with blood clotting, muscle contractions and communication between nerve cells.
“Ideally, calcium should come from a healthy diet with calcium-rich food. Your body is able to absorb more calcium from food than it can from supplements,” said Yariela Enriquez, M.D. [1], who practices internal medicine for the Baptist Health Medical Group. “But supplements can help complement calcium levels in those who are not meeting diet requirements and are most at risk, including post-menopausal women whose estrogen levels drop low and have increased bone loss.”
Both men and post-menopausal women with a family history of osteoporosis, hip fractures and low body weight are at risk, Dr. Enriquez said. For them, calcium and vitamin D supplements are prescribed as part of a treatment plan for osteoporosis, Dr. Enriquez said.
Bad Calcium
Bad calcium, however, is the remaining 1 percent of the body’s calcium. It’s found in blood, muscle and in the fluid between cells.
This is the type of calcium that cardiologists and other doctors warn against. It can accumulate as plaque inside the arteries, and can also lead to calcifications in soft tissue deposits elsewhere in the body. For example, breast calcifications are commonly seen on mammograms and are especially prevalent after menopause.
What many people may not realize is that a healthy diet rich in calcium has no correlation with the bad calcium deposits. Other factors are at play when calcium is deposited as plaque in the arterial walls, along with cholesterol and other substances in the process called atherosclerosis or hardening of the arteries.
More likely, people with hardening of the arteries lack a healthy diet and regular exercise, may have a family history of heart disease surfacing early in life, or have risk factors such as high blood pressure, high cholesterol, diabetes or smoke tobacco.
“There is the calcium you get from dairy products that’s good for you, but even though it’s elementally the same calcium, there is no correlation between calcium intake and coronary artery calcium deposits,” said Jonathan Roberts, M.D. [2], an interventional cardiologist at Baptist Cardiac and Vascular Institute.
When the innermost wall of an artery is damaged by risk factors, calcium, blood cells, fats and other cellular byproducts build up. That’s when the bad calcium, known to your cardiologist as “coronary calcium,” becomes a measurable danger to your health.
Coronary calcium may require attention if you are middle-aged with at least two risk factors for heart disease, including diabetes, smoking, hypertension, high cholesterol and a family history of early coronary artery disease, according to Roberts.
Almost everyone with atherosclerosis has some calcium buildup, he said. Since atherosclerosis is the predominant cause of heart attacks and strokes, calcium buildup in your coronary or carotid arteries could be a warning of future cardiovascular events.
Calcium Scoring
The role of calcium is increasingly coming to light as heart scans become more widely used to detect early heart disease in people with little or no symptoms or even risk factors.
For people diagnosed with atherosclerosis, a coronary CT angiogram can give doctors a calcium score. But, for those who don’t know that they have atherosclerosis but do have a family history of heart disease, a CT scan of the heart can give the same score without using contrast and with less radiation than a CT coronary angiogram.
That score can range from 0 to more than 400. According to research led by Khurrim Nasir, M.D., research director of Baptist Health’s Center for Wellness and Prevention, a coronary calcium score of zero puts a person at a very low risk of having a future heart attack. A score above 400 imparts a relatively high risk for having a future heart attack. Those with a score between 100 and 400 have a moderate risk for a future heart attack.
A coronary calcium score allows your doctor to proceed with different intensities of treatment, depending on the score. It may give your physician an idea of your future risk of having a heart attack, and may help direct how aggressive treatment should be for any risk factors you may have
A normal stress test only rules out severe atherosclerotic blockages in your coronary arteries. It can not rule out mild or moderate atherosclerotic buildup of plaque. An active person without chest pain but with risk factors could have a normal stress test but a high coronary calcium score. This person may be at increased risk for having a heart attack, and proper counseling and treatment by a physician may be in order.
“A calcium score can be incredibly helpful,” said Dr. Roberts.