Calcium Supplements: How Much Calcium Is Too Much?
Oct. 6, 2021 - Katie McCallumWe've likely all heard that "milk builds strong bones" — with calcium being the star ingredient.
It's one of bone's major components so it makes sense that getting plenty of calcium is important to keep them strong and healthy. Plus, it plays other important roles, such as supporting muscle movement, blood clotting and the release of hormones.
And having too little calcium? The consequences are considerable.
"Calcium deficiency can, over time, lead to weak and brittle bones, which is called osteoporosis," says Dr. Donald Brown, primary care practitioner at Houston Methodist. "It's characterized by reduced bone density, increased bone loss and a higher risk of hip, wrist and spine fractures. Many people don't get enough calcium, actually. But the good news is that this can often be corrected with dietary changes, especially in those younger people who might be lacking."
Hence, the famous "Got Milk" ad campaigns featuring milk mustaches on celebrities like Jonathan Taylor Thomas, the Olsen twins and Brett Favre. They drink milk! And we should, too.
But what about getting too much calcium? It's an especially relevant question for people who struggle to get enough calcium in their diet and wonder whether they should take supplements. Can calcium supplements ever do more harm than good?
How much calcium do you need per day?
The average adult needs 1,000 mg of calcium per day. The amount increases to 1,200 mg per day for women over the age of 50 and men over the age of 71.
"It's best for your calcium intake to come from your diet, which is very achievable since it's a mineral found in many foods," says Dr. Brown. "Those who follow a healthy diet are likely getting an optimal amount of calcium."
There's some disagreement, however, surrounding recommendations. Some experts say that 1,200 mg is higher than what the body actually needs. While a few studies have shown that increased calcium intake helps maintain optimal calcium balance and prevent fractures in postmenopausal women, several others fail to show a clear connection to fracture prevention and increased bone density.
"Regardless of whether 1,000 or 1,200 mg per day might be too high, meeting either requirement via your diet is usually still achievable," Dr. Brown says. "Just be sure you're eating a few servings of calcium-rich foods every day."
And if you're unsure whether you're getting enough calcium, consult with your doctor.
"Your physician can help you understand whether there are any dietary changes you may need to make, tests that may be needed to check for osteoporosis and if calcium supplementation is recommended," Dr. Brown adds.
Plus, it's not just calcium that you need to promote proper bone health. You need vitamin D, too.
"Vitamin D helps your body effectively absorb calcium," says Dr. Brown. "If you're vitamin D deficient, you may not be adequately absorbing enough of the calcium you're consuming — even if you're getting plenty of it. Sometimes optimizing your calcium balance is as simple as correcting a vitamin D deficiency, which is fairly common."
What's the best calcium supplement for osteoporosis?
Some people may have a hard time getting sufficient calcium via their diet, while others may already have bone loss that puts them at higher risk of osteoporosis.
"This is when a person might consider taking a calcium supplement, but it's important to consult your doctor about this first," says Dr. Brown.
You'll need help to determine the type of calcium supplement that's best for you, as well as the correct dose and timing of supplementation.
"Calcium carbonate is the less expensive option, but it must be taken with a low-iron meal," says Dr. Brown. "Additionally, some medications prevent absorption of this type of calcium, so it's important to review your medications with your doctor beforehand."
Calcium citrate is the other calcium supplement option. Its benefit is that you can take it on an empty stomach. But be wary of any calcium citrate supplements containing more than 500 mg of calcium per dose.
"Your body has trouble absorbing more than 500 mg of calcium at a time. Any extra calcium will likely just be passed through your system into your urine," adds Dr. Brown.
Lastly, there's an upper limit to calcium consumption — what you're consuming via your diet and any supplement you're taking.
"Adults shouldn't consume more than 2,000 mg of calcium per day," cautions Dr. Brown. "Exceeding this limit can result in side effects and even complications."
Do calcium supplements have side effects?
One of the main reasons to get the majority of your calcium through your diet, rather than a supplement, are the side effects that can accompany taking a calcium supplement, including:
- Gas, bloating and constipation
- Indigestion
"There's also the potential for adverse effects," warns Dr. Brown. "For instance, calcium supplements may lead to kidney stones since they cause more calcium to be eliminated via the urine. Additionally, these supplements might increase a person's risk of heart disease and prostate cancer, although the evidence is mixed and more research is needed."
Importantly, the side effects and complications seen with prolonged use of calcium supplements aren't seen when calcium is consumed through diet.
Before trying a supplement, make sure you're eating calcium rich foods and exercising
Rather than relying on a supplement, Dr. Brown recommends first trying to optimize your calcium intake naturally.
"You can help ensure you're getting enough calcium by consuming between two and four servings of calcium-rich foods per day," says Dr. Brown.
Calcium-rich foods include:
- Low-fat dairy: yogurt (plain or Greek), milk (low-fat, skim or whole) and certain cheeses (part-skim ricotta, part-skim mozzarella and cheddar)
- Green leafy vegetables: collard greens, kale, bok choy and broccoli
- Seafood with soft bones that you can eat: sardines and canned salmon
- Calcium-fortified foods: soy products (tofu) and milk substitutes (almond milk and soy milk), as well as certain orange juices and cereal
"In addition to eating a calcium-rich diet, exercise is a great way to build and maintain strong bones," says Dr. Brown. "And it's never too late to add exercise into your routine to help slow bone loss."
Walking, jogging, running and using an elliptical machine help maintain bone density in your legs, hips and lower spine. Strength training, which includes body weight exercises, helps maintain the bones in your upper body, including your arms and upper spine.
"There generally aren't any obvious short-term symptoms of calcium deficiency, so if you're at all worried about your calcium levels — either due to your diet or having a history of a sedentary lifestyle — start by consulting your doctor," says Dr. Brown. "Calcium supplements might be needed to support dietary and exercise changes, but this isn't always the case."