Q.
A recent heart scan showed a very high calcium score. Do I need to change my diet and eat foods lower in calcium?

A. A coronary artery calcium scan uses low-radiation CT to measure calcium deposits in the coronary arteries that surround the heart and supply oxygen- and nutrient-rich blood to the heart muscle cells. Calcium deposits within these arteries are often accompanied by atherosclerosis, a common condition that narrows and “hardens” the arteries and increases the risk of heart attack.

It is natural for foods and drinks containing calcium to be associated with calcium deposits in the body. However, eating foods high in calcium has no effect on what happens in your arteries. In fact, many observational studies have shown that people who consume more calcium in their diets are more likely to have lower blood pressure and lower risk of cardiovascular disease.

The exact reason why hard deposits of calcium crystals form in some areas of the body is unknown. Researchers have noticed that damaged tissue can undergo changes that cause cells to adopt bone-like structures. Our bones naturally attract calcium, so these tissues can also absorb calcium. When fatty deposits form in the coronary arteries (or other arteries in the body), the artery walls adjacent to the deposits can become inflamed and damaged, leading to the formation of bone-like cells and calcium deposits. Calcium levels measured in a coronary heart scan are therefore a proxy for the amount of fatty plaque buildup.

Once calcium is deposited in the arteries, it cannot be replaced. However, the process can be slowed down by actively addressing the risk factors that lead to the formation of fatty deposits in the arteries. This means maintaining normal blood pressure and lowering “bad” LDL cholesterol.

If you have a high coronary artery calcium score, most doctors will recommend high-dose statins to lower your LDL below 70 milligrams per deciliter (mg/dL) or even below 55 mg/dL. . To reach that goal, you may need to take a second cholesterol-lowering drug in addition to a statin.

A similar calcification process occurs in aortic valves that have been damaged over decades, resulting in a narrow, stiff, calcified aortic valve known as aortic stenosis. However, lowering LDL cholesterol does not slow the narrowing in this condition.

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