illustration of woman eating yogurt with other sources of calcium floating in back

You eat your yogurt, exercise daily and chew that calcium supplement like a champ. Osteoporosis doesn't stand a chance — you're a calcium superstar!

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But, when it comes to calcium, it's actually possible to have too much of a good thing: Calcium can build up to unhealthy levels in the bloodstream. And this hypercalcemia can cause a variety of problems ranging from not great to very serious.

Don't toss your calcium supplements just yet, though. Endocrinologist Susan Williams, MD, explains what happens when calcium levels creep too high — and how to strike a healthy balance.

The dangers of high calcium levels

Calcium is key to a sturdy skeleton. "Calcium is so important for the bones and teeth of growing children, but as adults, we sometimes forget how important it is throughout our lifetime," Dr. Williams says.

Besides beefing up bones, calcium is critical for the healthy function of nerves and muscles, including the heart.

Guidelines recommend a total of 1,000 milligrams per day for women until age 50 and for men until age 70.

Past those birthdays, men and women should aim for 1,200 mg per day. (For context, a cup of milk or a serving of yogurt each has about 300 mg of calcium.)

More is not better, however. Problems linked to excess calcium include:

  • Constipation.
  • Kidney stones.
  • Kidney failure.
  • Heart function problems.
  • Confusion and cognitive problems.

What causes hypercalcemia?

Soaring calcium levels can be triggered by a variety of diseases, including parathyroid problems and a number of cancers. Hypercalcemia can also be a side effect of certain prescription meds.

But over-the-counter calcium medications can push you over the edge, too. It's surprisingly easy to overdo the calcium supplements — especially if you consume a lot of dairy or otherwise get plenty from your food. Over-the-counter antacid chews and tablets pack a big calcium punch as well.

On top of all that, high doses of vitamins A and D can also cause calcium levels to rise.

Hypercalcemia hints

Many people don't have obvious symptoms of hypercalcemia. But these signs hint that your calcium levels might be flying high:

  • Bone pain.
  • Headaches.
  • Fatigue and lethargy.
  • Frequent urination and thirst.
  • Nausea, constipation and/or loss of appetite.
  • Muscle aches, weakness or cramping.
  • Memory problems, irritability and depression.

Luckily, hypercalcemia caused by supplements and antacids usually reverses quickly when you stop taking them, Dr. Williams says. Untreated, though, long-term hypercalcemia can be serious — maybe even life-threatening.

Avoid calcium overload

How can you make sure you're getting enough calcium without going overboard?

  1. Think food first. Foods rich in calcium include dairy products, sardines and leafy greens like kale and broccoli. Unless you're on an all-dairy diet (note: do not go on an all-dairy diet), you probably won't get too much calcium from food alone. Consider it a good reason to eat more ice cream.
  2. Drink up. Dehydration can lead to mild hypercalcemia, when the amount of fluid in your blood gets too low, so keep your water bottle filled and ready.
  3. Do the math. Between multivitamins, supplements, antacids and your morning yogurt, your daily calcium intake can add up faster than you realize. Pay attention to how much you're really consuming.
  4. Schedule a check-up. Most physicians check calcium levels during routine blood tests that you get in an annual exam. It's one more reason to check in with your doctor on the regular.
  5. Supplement with care. Talk to your doctor about whether you should take calcium and vitamin D supplements, and if so, how much you need. "Without a doubt, getting adequate calcium is good for your bones. But taking more than you need won't make your bones stronger," Dr. Williams says. Sometimes, enough is enough.