Calcium is a mineral that’s important for many of the body’s functions, including bone and heart health.
Some studies have linked calcium supplements to heart problems, like heart attacks. This may be related to calcium buildup in the heart’s blood vessels.
It’s unclear whether taking calcium supplements directly contributes to heart disease. Talk to your healthcare provider before starting a calcium supplement.
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Calcium is a mineral that plays a crucial role in many tissues, especially your skeletal system. In fact, more than 99% of calcium in your body is stored in your bones and teeth. It’s generally recommended that adults receive at least 1,000 mg of calcium each day to ensure good bone health.
But how else does calcium affect the body? And can taking too much be dangerous for your health? It’s estimated that over 40% of people in the U.S. take dietary supplements containing calcium. Could some of these people be at higher risk for certain complications?
Here, we’ll talk about whether calcium supplements can raise your risk of heart disease.
Besides your bones and teeth, calcium also affects organs like your heart. Calcium enters the muscle cells in your heart during every heartbeat. This helps coordinate the electrical signals that control how fast your heart beats. Calcium is also involved in helping the heart contract and pump blood to the rest of the body. In fact, calcium is involved in helping all muscles in the body contract.
There are some concerns that calcium supplements may raise the risk of heart problems, including heart attacks. Some researchers believe that taking too much calcium can lead to calcification of blood vessels in the heart.
Blood vessel (or vascular) calcification occurs when minerals like calcium build up in the walls of your veins and arteries. This includes blood vessels of the heart (coronary arteries). Vascular calcification can block blood from flowing to your heart, which can lead to heart disease.
Vascular calcification is often a sign of atherosclerosis. This is the buildup of fatty deposits — or plaques — on the inner walls of your arteries. Atherosclerosis can raise your risk of heart attack, stroke, or even death.
Studies have tried to determine whether calcium — and calcium supplements in particular — have a negative effect on the heart. In 2010, a large meta-analysis suggested calcium supplements were linked to a higher risk of having a heart attack.
But, the overall risk (absolute risk) of a heart attack was still very low, even in those that took calcium supplements. Out of over 8,000 study participants, 143 people taking a calcium supplement experienced a heart attack compared to 111 people who didn't take calcium.
And a 10-year follow-up study of over 5,000 people looked at whether high calcium intake was linked to hardening of the arteries (atherosclerosis). The study found that high calcium intake — about 1,400 mg or more — may lower the risk of atherosclerosis. This was especially true if the person’s calcium came from food only. But, taking calcium supplements was linked to a higher risk of blood vessel calcification. The researchers concluded that dietary calcium might protect the heart, but that calcium supplements may have heart risks associated with them.
Other studies have found that calcium supplementation doesn’t raise the risk of heart problems. For example, one analysis found that up to 2,500 mg per day of calcium wasn’t associated with a higher risk for heart disease. This includes calcium from the diet, supplements, or both.
Women taking calcium supplements may be at higher risk for heart problems than men.
A large study showed that women who have gone through menopause may be at greater risk for heart disease if they take calcium supplements of 1,000 mg per day. There was even greater risk in women who got 700 to 1,000 mg of calcium per day in their diet. But it’s unclear how significant these risks really are.
Another analysis of over 36,000 women who had gone through menopause showed that combined calcium and vitamin D supplements didn’t raise the risk of heart disease. But, it’s important to mention that the studies in this analysis were designed to evaluate the benefits of supplementation on fracture risk — not heart disease.
The evidence on whether calcium supplements raise the risk of heart disease isn’t clear. We don’t know for sure whether calcium supplements can raise your chance of developing heart disease. Still, it might be best to get the calcium you need from the food you eat. However, because calcium is so important for your body and bone health, some people still might need calcium supplements.
There are some people that may be more likely to have problems with calcium, so always talk to your healthcare provider before starting a calcium supplement. Some people who might be at greater risk of side effects include people with kidney problems and people with a history of kidney stones.
If your kidneys don’t function normally, you may sometimes take calcium — such as calcium acetate — to lower phosphorus levels. But don’t take more calcium than what’s prescribed. Too much calcium can cause calcium to bind with phosphorus and deposit in your blood vessels — including the heart. Talk to your healthcare provider or dietitian about the amount of calcium that’s recommended for you.
People with a history of kidney stones may know that they’re most commonly caused by calcium combining with oxalate in the urine. Oxalate is a natural substance in many foods that can cause crystals to form in the urine. Calcium from supplements raises the chance that calcium combines with oxalate. But, don’t avoid calcium in your diet. Getting enough calcium from your food may be helpful in preventing kidney stones.
We don’t know for sure. Research doesn’t suggest that all people with heart disease should avoid taking calcium supplements. And again, some studies show that getting enough calcium in your diet may help prevent atherosclerosis. It’s important to discuss with your healthcare provider first before taking any calcium supplement. Although calcium is important for your bone health, getting too much calcium can sometimes lead to serious side effects.
Calcium is an important element for many of your body’s functions, including bone health, muscle contraction, and heart health. Some research suggests that calcium supplements may lead to heart problems. This is because calcium can contribute to blockage inside your heart’s blood vessels.
But, it’s unclear just how much calcium supplements contribute to this risk. It’s important to talk to your healthcare provider or pharmacist before starting a calcium supplement. This will help you learn how much calcium you need, and whether you need a supplement at all.
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