Calcium is a mineral your body needs to build and maintain strong bones and perform many important functions. Calcium is the most abundant mineral in the body.

Almost all calcium in the body is stored in bones and teeth, giving them structure and hardness.

Muscles need calcium to move and nerves to carry messages between the brain and every part of your body. Calcium also helps blood vessels move blood throughout the body and helps secrete hormones that affect many functions in your body.

• Age
• Recommended Amount
• From birth to 6 months
• 200mg
• 7-12 month old babies
• 260 mg
• Children 1-3 years old
• 700 mg
• Children 4-8 years old
• 1000 mg
• Children aged 9-13
• 1300mg
• Young people aged 14-18
• 1300mg
• Adults aged 19-50
• 1000 mg
• Men aged 51–70
• 1000 mg
• Women aged 51–70
• 1200mg
• People aged 71 and over
• 1200mg
• Pregnant and breastfeeding teenagers
• 1300mg
• Pregnant and breastfeeding adults
• 1000 mg

Which Foods Contain Calcium?

Calcium is found in many foods. You can get the recommended amount of calcium by eating a variety of foods, including:

• Milk, yoghurt and cheese contain high amounts of calcium.
• Canned sardines and salmon with bones contain calcium.
• Some vegetables, such as cabbage, broccoli and bok choi, also contain calcium.
• Calcium is added to some beverages, including many juices and milk substitutes, such as soy and almond beverages, and some brands of tofu and ready-to-eat cereals. Check product labels to see if calcium is added to these foods.
• Most grains (such as bread, pasta, and unfortified cereals) do not contain high amounts of calcium. However, as people eat them frequently, their contribution to total calcium intake increases.

What Types of Calcium Dietary Supplements Are Available?

Calcium is found in many multivitamin-mineral supplements, calcium supplements, and supplements containing other nutrients such as calcium and vitamin D.

The two main forms of calcium in dietary supplements are calcium carbonate and calcium citrate. Calcium carbonate is best absorbed when taken with food. Some over-the-counter antacids, such as Tums and Rolaids, also contain calcium carbonate.

Calcium citrate is well absorbed on an empty stomach or on a full stomach. People with low stomach acid levels (a condition most common in older people) absorb calcium citrate more easily than calcium carbonate.

Other forms of calcium in supplements and fortified foods include calcium sulfate, calcium ascorbate, calcium microcrystalline hydroxyapatite, calcium gluconate, calcium lactate, and calcium phosphate.

Calcium is best absorbed when you take 500 mg or less at a time. For example, if you are taking 1000 mg/day from supplements, it is better to take a smaller dose twice a day rather than taking it all at once.

Calcium supplements can cause gas, bloating, and constipation in some people. If you have any of these symptoms, try spreading your calcium dose throughout the day, taking the supplement with meals, or changing the form of calcium you take.

Am I Getting Enough Calcium?

Many people get less than recommended amounts of calcium from foods and supplements, especially:

• Children and young people aged 4 to 18
• People who are black or Asian
• Adults 50 and older living in poverty

Certain groups of people are more likely than others to have problems getting enough calcium, including:

• Post-menopausal women: After menopause, the body absorbs and retains less calcium. Over time, this can lead to brittle bones.
• People who do not drink milk or eat other dairy products: Dairy products are rich sources of calcium, but people with lactose intolerance, people with milk allergies, and vegans (people who do not consume animal products) should find other sources of calcium. Options include lactose-free or reduced-lactose dairy products; canned fish with bones; some vegetables such as cabbage, broccoli and bok choy; calcium-fortified juices and milk substitutes, such as soy and almond beverages, tofu, and ready-to-eat cereals; and dietary supplements containing calcium.

What Happens If I Don't Get Enough Calcium?

Getting too little calcium can cause a variety of effects, including:

• Osteoporosis, which causes weak, brittle bones and increases the risk of falls
• Rickets, a disease that causes soft, weak bones in children
• Osteomalacia, which causes soft bones in children and adults

What Are Some Effects of Calcium on Health?

Scientists are studying calcium to understand how it affects health. Here are a few examples of the results of these studies:

Bone health in older adults

After about age 30, bones gradually lose calcium. Bone loss accelerates in middle age and can lead to weak, brittle bones (osteoporosis) and broken bones (fractures). Although bone loss is more common in women, it can also affect men.

The health of your bones is measured with a bone mineral density test, which tells you whether your bones are healthy and strong or weak and thin. Some studies have found that calcium supplements with or without vitamin D increase bone mineral density in older adults, but others do not. Also, it is not clear whether calcium supplements help prevent fractures. More research is needed to better understand whether consuming more calcium from food or supplements improves bone health in older adults.

Cancer

Some research shows that people who get high amounts of calcium from foods and supplements have a lower risk of colon and rectal cancer, but other research does not support this. Some studies have shown that men who consume high amounts of calcium from dairy products have an increased risk of prostate cancer. For other types of cancer, calcium does not seem to affect the risk of getting or dying from cancer. More research is needed to better understand whether calcium from foods or dietary supplements affects cancer risk.

Heart disease

Calcium can stick to fats and reduce the amount of fat your body absorbs. Some studies show that calcium supplements have no effect on heart disease, while others show that calcium supplements may increase the risk of heart disease. In general, experts believe that calcium intake from foods or supplements with or without vitamin D does not affect the risk of heart disease or death from heart disease (see Can calcium be harmful).

Preeclampsia

Preeclampsia is a serious complication seen in later stages of pregnancy. Symptoms include high blood pressure and high levels of protein in the urine. Calcium supplements may reduce the risk of preeclampsia in some pregnant women who consume too little calcium. That's why many experts recommend calcium supplements during pregnancy for women with low calcium intake.

Weight management

Research hasn't clearly shown whether calcium from dairy products or supplements helps you lose weight or prevents weight gain. Some research shows that consuming more calcium helps, but other studies do not support this.

Metabolic syndrome

Metabolic syndrome is a serious medical condition that increases your risk of heart disease, stroke, and diabetes. You have metabolic syndrome if you have three or more of the following:

• A wide waist
• High levels of fats in the blood (triglycerides)
• Low levels of high-density lipoprotein cholesterol (good cholesterol)
• high blood pressure
• high blood sugar levels

Some research suggests that higher calcium intake may help reduce the risk of metabolic syndrome in women but not men. More studies are needed.

Calcium and Healthy Nutrition

People should get most of their nutrients from food and drink. Foods contain vitamins, minerals, dietary fiber and other components that benefit health. In some cases, fortified foods and dietary supplements are useful when it is not possible to meet the needs of one or more nutrients (for example, during certain life stages, such as pregnancy).

Disclaimer

This fact sheet, prepared by the Office of Dietary Supplements (ODS), provides information that should not replace medical advice. We encourage you to talk with your healthcare providers (doctor, registered dietitian, pharmacist, etc.) about your interest in, questions about, or use of dietary supplements and what may be best for your overall health. Mention of a particular product or service or recommendation from an organization or professional society in this publication does not imply endorsement by ODS of that product, service, or professional advice.

Source:

1. This article was translated from the Calcium article.

Note: This translation has not been checked by ODS.