Actions for this page Listen Print. Summary Read the full fact sheet. On this page. Role of calcium in the body Calcium and dairy food Too little calcium can weaken bones Calcium needs vary throughout life People with special calcium needs Good sources of calcium Calcium supplements Calcium supplements — complications Lifestyle can affect bone strength Where to get help. According to the most recent National Nutrition and Physical Activity Survey of —12 : Over half of all Australians aged two years and over consume inadequate levels of calcium from food sources.
Females are less likely to have adequate intakes of calcium than males. Role of calcium in the body Calcium plays a role in: strengthening bones and teeth regulating muscle functioning, such as contraction and relaxation regulating heart functioning blood clotting transmission of nervous system messages enzyme function. Calcium and dairy food Australians receive most of their calcium from dairy foods. Too little calcium can weaken bones If not enough calcium is circulating in your blood, your body will use hormones to reduce the amount of calcium your kidneys excrete in your urine.
Calcium needs vary throughout life The recommended dietary intake of calcium is different for people of different ages and life stages. Food type Examples Calcium per serve mg Milk and milk products Milk, yoghurt, cheese and buttermilk One cup of milk, a g tub of yoghurt or ml of calcium-fortified soymilk provides around mg calcium. Calcium-fortified milks can provide larger amounts of calcium in a smaller volume of milk — ranging from mg to mg per ml milk.
Leafy green vegetables Broccoli, collards cabbage family , bok choy, Chinese cabbage and spinach One cup of cooked spinach contains mg, although only five per cent of this may be absorbed. This is due to the high concentration of oxalate, a compound in spinach that reduces calcium absorption. By contrast, one cup of cooked broccoli contains about 45 mg of calcium, but the absorption from broccoli is much higher at around 50—60 per cent.
Soy and tofu Tofu depending on type or tempeh and calcium fortified soy drinks One cup, or g of tofu contains around mg of calcium.
One cup of tempeh contains around g of calcium. Fish Sardines and canned salmon bones included Half a cup of canned salmon contains mg of calcium.
Nuts and seeds Brazil nuts, almonds and sesame seed paste tahini Fifteen almonds contain about 40 mg of calcium. Calcium-fortified foods Breakfast cereals, fruit juices, bread, some plant-based milks One cup of calcium-fortified breakfast cereal 40 g contains up to mg of calcium. Half a cup of calcium-fortified orange juice ml contains up to 80 mg of calcium, and two slices of bread 30 g provide mg of calcium. Plant-based milks oat, almond, rice, etc. Calcium , , Osteoporosis Australia.
Are calcium supplements dangerous? Australian health survey: usual nutrient intakes, —12 , Australian Bureau of Statistics, Australian Government. Give feedback about this page. Was this page helpful? High calcium intake—from either food or pills—doesn't reduce hip fracture risk. This was the conclusion of a report by Swiss and American scientists who conducted an analysis of more than a dozen studies of calcium.
The studies also revealed a couple of downsides to high levels of calcium supplementation, but not to calcium obtained through a regular diet:. An increased risk of kidney stones. In the Woman's Health Initiative, women taking the calcium—vitamin D combination had a higher risk of developing kidney stones than those who got the placebo. Although high levels of dietary calcium are thought to offer some protection against kidney stones, high doses of calcium from supplements may promote stone formation by increasing the amount of calcium that is eliminated in the urine.
An increased risk of heart attack. In a randomized study of 1, postmenopausal women conducted in New Zealand, 21 of women who took 1, mg of calcium a day had heart attacks, compared with 10 of who received a placebo. A analysis of 15 randomized controlled trials also linked calcium supplementation with an increased risk of heart attack. Vitamin D is also essential for healthy bones. In fact, the daily vitamin D requirement was first introduced to help prevent rickets—a condition in which developing bones are soft and can become bowed—in children.
Vitamin D is made in the skin through exposure to ultraviolet radiation in sunlight. However, the amount produced varies widely from person to person. People with darker skin produce less vitamin D than lighter-skinned people, and in all populations, the skin's ability to convert sunlight to vitamin D declines with age.
Plus, if you follow the advice to reduce your risk of skin cancer by keeping covered and wearing sunscreen, you're also cutting your vitamin D production. Such variability has made it difficult for researchers to tell how much vitamin D people make in addition to the amount they consume in supplements.
Evidence from studies that have measured blood levels of vitamin D indicates that levels in the high-normal range are optimal for building bone. To reach those levels may require taking to 1, IU of vitamin D a day. One thing the studies have taught us is that both calcium and vitamin D are essential in building bone. The question is how much of each. Willett recommends going lower on calcium and higher on vitamin D than the guidelines suggest— to mg a day of calcium and to 1, IU of vitamin D.
At that rate, you can probably get all or most of your calcium from food, especially if you have a serving or two of dairy products daily. If you can't tolerate dairy, you should still be able to get mg a day in your diet and can take a low-dose calcium supplement to make up the rest. By keeping your supplement consumption to mg or less a day, you should avoid the possible risk of heart disease and kidney stones suggested by the studies. Although vitamin D is added to milk and some other foods, you'll probably need a supplement to be sure you're getting enough.
A capsule containing to 1, IU should do the trick. As a service to our readers, Harvard Health Publishing provides access to our library of archived content.
Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
Many Americans don't get enough calcium in their diets. Children and adolescents are at risk, but so are adults age 50 and older. The recommended upper limit for calcium is 2, mg a day for adults 19 to For those 51 and older, the limit is 2, mg a day.
Your body doesn't produce calcium, so you must get it through other sources. Calcium can be found in a variety of foods, including:. To absorb calcium, your body also needs vitamin D. A few foods naturally contain small amounts of vitamin D, such as canned salmon with bones and egg yolks. You can also get vitamin D from fortified foods and sun exposure. The RDA for vitamin D is international units 15 micrograms a day for most adults. Even if you eat a healthy, balanced diet, you may find it difficult to get enough calcium if you:.
In these situations, calcium supplements may help you meet your calcium requirements. Talk with your doctor or dietitian about whether calcium supplements are right for you.
Calcium supplements aren't for everyone. For instance, if you have a health condition that causes excess calcium in your bloodstream hypercalcemia , you should avoid calcium supplements. It's not definitive, but there may be a link between high-dose calcium supplements and heart disease. The evidence is mixed and more research is needed before doctors know the effect calcium supplements may have on heart attack risk. A similar controversy surrounds calcium and prostate cancer.
Some studies have shown that high calcium intake from dairy products and supplements may increase risk, whereas another more recent study showed no increased risk of prostate cancer associated with total calcium, dietary calcium or supplemental calcium intakes. Until more is known about these possible risks, it's important to be careful to avoid excessive amounts of calcium. As with any health issue, it's important to talk to your doctor to determine what's right for you. Several different kinds of calcium compounds are used in calcium supplements.
Each compound contains varying amounts of the mineral calcium — referred to as elemental calcium. Common calcium supplements may be labeled as:. The two main forms of calcium supplements are carbonate and citrate.
Calcium carbonate is cheapest and therefore often a good first choice. Other forms of calcium in supplements include gluconate and lactate. In addition, some calcium supplements are combined with vitamins and other minerals. For instance, some calcium supplements may also contain vitamin D or magnesium. Check the ingredient list to see which form of calcium your calcium supplement is and what other nutrients it may contain.
This information is important if you have any health or dietary concerns. Elemental calcium is important because it's the actual amount of calcium in the supplement. It's what your body absorbs for bone growth and other health benefits. The Supplement Facts label on calcium supplements is helpful in determining how much calcium is in one serving.
Be sure to note the serving size number of tablets when determining how much calcium is in one serving. Calcium supplements cause few, if any, side effects. But side effects can sometimes occur, including gas, constipation and bloating.
In general, calcium carbonate is the most constipating. You may need to try a few different brands or types of calcium supplements to find one that you tolerate the best. Calcium supplements can interact with many different prescription medications, including blood pressure medications, synthetic thyroid hormones, bisphosphonates, antibiotics and calcium channel blockers.
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