What Is Calcium?
Calcium is a mineral that’s well-known for its key role in bone health. Calcium also helps maintain heart rhythm, muscle function, and more. Because of its health benefits, calcium is one of the best-selling supplements in the U.S.
Calcium Health Benefits
Calcium is key to growing new bone and keeping the bone you have strong. Calcium supplements are standard for treating and preventing osteoporosis — weak and easily broken bones — and its precursor, osteopenia.
Calcium has many other uses. It’s an ingredient in many antacids. Doctors also use it to control high levels of magnesium, phosphorus, and potassium in your blood. There’s good evidence it can help prevent or control high blood pressure. It may also ease PMS symptoms and play a role in preventing certain cancers. Some research shows that calcium with vitamin D, for instance, may help protect premenopausal women from breast cancer. Calcium also has been studied as a weight loss aid. But so far, these studies have been inconclusive.
The people most likely to have too little calcium are postmenopausal women. Since dairy products are one of the most common sources of calcium, people who are lactose intolerant or vegan may not get enough, either.
The Institute of Medicine has set dietary reference intake (DRI) and recommended daily allowance (RDA) standards for calcium. Getting this amount from the food you eat, with or without supplements, may be enough to keep your bones healthy. Doctors may recommend higher doses.
Women who are pregnant or breastfeeding don’t need amounts beyond the recommendations above.
The tolerable upper intake levels (ULs) of a supplement are the highest amount that most people can take safely. For calcium, it’s:
- Infants 0-6 months: 1,000 mg/day
- Infants 7-12 months: 1,500 mg/day
- Children 1-8 years: 2,500 mg/day
- Children/teens 9-18 years: 3,000 mg/day
- Adults 19-50 years: 2,500 mg/day
- Adults over 51 years: 2,000 mg/day
In general, it’s best to take calcium supplements with food. For better absorption, don’t take more than 500 milligrams at one time. Split up larger doses over the course of the day. For your body to make use of calcium properly, you also need to get enough vitamin D and magnesium.
Natural Calcium Sources
Good sources of calcium include:
- Broccoli, kale, and Chinese cabbage
- Fortified cereals, juices, soy products, and other foods
Experts say that most adults in the U.S. don’t get enough calcium. While improving your diet will help, you may need to take calcium supplements.
Who Should Consider Calcium Supplements?
You may want to talk to your doctor about calcium supplements and the best way to take them if you:
- Follow a vegan diet
- Can’t digest lactose (you’re lactose intolerant)
- Eat or drink a lot of protein or sodium, which can cause your body to get rid of more calcium
- Have thin, weak bones (osteoporosis)
- Take long-term corticosteroid treatments
- Have bowel or digestive diseases and can’t absorb calcium well
- Side effects. At normal doses, calcium supplements may cause bloating, gas, and constipation. Very high doses of calcium can cause kidney stones. Some studies show taking calcium supplements in addition to a diet high in calcium could raise your risk of heart attacks and strokes, but other experts disagree.
- Interactions. If you take any prescription or over-the-counter medicines regularly, ask your doctor if it’s safe to use calcium supplements. Calcium can interact with drugs for heart disease, diabetes, epilepsy, and other conditions. High doses of vitamin D can result in dangerously high levels of calcium. High doses of calcium can also prevent your body from absorbing minerals like iron and zinc. In general, take calcium one to two hours apart from other supplements or medications. If you take them at the same time, calcium can bind to those products, and they’ll pass from your body unabsorbed.
- Risks. If you have kidney disease, heart problems, sarcoidosis, or bone tumors, don’t take calcium supplements unless your doctor suggests them.
- Overdose. High levels of calcium in your blood can cause nausea, dry mouth, belly pain, an irregular heartbeat, confusion, and even death.
There’s no need to use products identified as “coral calcium." Claims made that coral calcium is better than regular calcium are unproven. Also, coral calcium products may contain dangerous amounts of lead.
Referenced on 21/05/2021
- Longe, J.L., ed. The Gale Encyclopedia of Alternative Medicine, second edition, 2004.
- Office of Dietary Supplements: “Calcium."
- Natural Marketing Institute’s 2007 Health & Wellness Trends Database.
- Natural Standard Patient Monograph: “Calcium."
- WebMD Feature: “Boning up on Calcium: Supplements for Bone Health."
- Mayo Clinic: “Calcium and calcium supplements: Achieving the right balance.”