Surprising Side Effects of Taking Calcium Supplements, Says Science

Calcium is an essential nutrient that can keep your bones and muscles strong and your teeth healthy. While the nutrient can be found in foods like dairy, dark leafy greens, seeds, canned sardines, and certain beans, many people choose to take supplements to increase their calcium intake—but doing so isn't always as safe as it may seem.

If you're thinking of boosting your calcium intake, read on to discover the side effects of taking calcium supplements (the good and the bad), according to science. And for some supplements you may want to add to your daily routine, check out The One Vitamin Doctors Are Urging Everyone to Take Right Now.

You may lose weight.

woman weighing herself overweight on scale — Shutterstock

If you've had trouble slimming down in the past, adding some extra calcium to your routine may help you shed those extra pounds. According to a 2013 study published in Nutrition Journal, among individuals with very low calcium intakes, adding a calcium and vitamin D supplement to their calorie-restricted diet not only helped them lose weight, but it also promoted greater fat loss than that which occurred in individuals who restricted calories alone. While it's unclear how much of this effect is attributable to changes in study subjects' vitamin D status, other studies have demonstrated a significant link between increased calcium consumption and weight loss, as well.

For more simple ways to slim down, check out these 15 Underrated Weight Loss Tips That Actually Work.

You may lower your blood pressure.

nurse checking woman's blood pressure — Shutterstock

If you've been dealing with high blood pressure, you may want to ask your doctor if adding calcium supplements to your routine can help. A 2015 study published in Cochrane Library found that, among a group of 3,048 study subjects who took part in 16 clinical trials, increased calcium intake was associated with reductions in subjects' systolic and diastolic blood pressure, with the results being especially pronounced among individuals under age 35.

You may reduce your risk of macular degeneration.

Macular degeneration, a condition that causes progressive vision loss and in some cases may cause blindness, may be less likely to occur among individuals taking calcium supplements, research suggests. A 2019 study published in JAMA Ophthalmology found that, among a study population of 4,751 adults, those who took the highest amounts of calcium supplementation had the lowest risk of developing neovascular age-related macular degeneration compared to those who took the lowest levels of calcium supplementation. For the latest health and weight loss news delivered to your inbox, sign up for our newsletter!

You may increase your risk of heart problems.

woman who is suffering from a chest pain and touching her heart area — Shutterstock

While research has found that higher dietary calcium intake may help reduce a person's risk of developing heart problems, calcium supplementation may have the opposite effect. A 2016 study published in the Journal of the American Heart Association found that among 5,448 adults without cardiovascular disease diagnoses, those with the highest levels of dietary calcium had lower levels of coronary artery calcification (CAC). However, the study's authors "found evidence that calcium supplement use was independently associated with incident CAC," a condition that can increase a person's risk of having a cardiovascular event.

Your risk of colon polyps may rise.

middle aged woman sitting on bed with stomach pain — Shutterstock / fizkes

Individuals with gut health issues would be wise to consult a medical professional before making calcium supplementation a regular habit. A 2018 study published in the journal Colon found that among individuals who had had at least one colon polyp that had been removed, those who took either calcium supplementation or a combination of calcium and vitamin D were more likely to develop polyps in the 6-10 year period after supplementation began that those who didn't increase calcium supplementation. If you want to improve the health of your digestive tract in the long run, check out the 20 Best Foods for Gut Health!