Essential for life, calcium is the most abundant mineral in the human body. Typically, 99% of the calcium in the body is found in the teeth and bones. Calcium also plays a role in blood clots, nerve function, and muscular movement. It is especially important for children to receive adequate amounts of calcium as their bones grow and form more rapidly than any other age group.

Calcium benefits

Calcium offers a variety of health benefits that extend beyond building strong bones. As humans reach their 30's, the body tends to lose more bone than it will create. This decrease in bone density can lead to a condition called osteoporosis where the bones become weak and porous, resulting in a higher likelihood of breaks and fractures. Consuming the recommend daily amounts of calcium allows the body to continuously use this influx of the mineral to keep bones strong and healthy.

Other benefits of calcium (all of which should be discussed with your doctor prior to applying a self-medication process) include: reducing high blood pressure, aid in weight loss, lowering cholesterol, treatment of Rickets (soft and weak bones in children), reducing probability of stroke, and a lowering the risk of colon cancer. These studies all require more research before definitive conclusions can be met.

Sources of calcium

Dairy products such as milk, cheese, and yogurt generally contain large amounts of calcium. There are non-dairy foods that also contain moderate amounts of calcium and they are various nuts (almonds, Brazil nuts), vegetables (broccoli, turnips, collard greens, mustard greens, kale), and some seafood also contains calcium (oysters, sardines, canned salmon).

Foods fortified with calcium are quite common. This includes various juices, non-dairy based milks (soy, rice), tofu, and cereals. To aid in the absorption process, these foods are typically fortified with vitamin D in addition to calcium. For those that experience a lactose intolerance, these fortified foods (and sometimes further boosted with a supplement) are an individual's primary source of calcium.

When calcium is offered as a supplement, it is most common in two forms: calcium citrate and calcium carbonate. The citrate version is easily absorbed and digested but the amount of elemental or usable calcium is less than the amount found in the carbonate supplement. The carbonate version is usually taken with a glass of orange juice to aid the acids of the stomach with the digestion and absorption process.

Recommended amounts

Set forth by the Institute of Medicine, the daily recommendations for calcium are below (some individuals may be placed on a plan that requires higher than normal amounts to manage a specific issue they may be experiencing).

Table 1: Daily Recommendations for calcium1
Age Amount
0-6 months 200mg
7-12 months 260mg
1-3 years 700mg
4-8 years 1000mg
9-18 years 1300mg
19-50 years 1000mg
Males 51-70 years 1000mg
Females 51+ years 1200mg
Males 70+ years 1200mg
Pregnant or Nursing Females under 19 years 1300mg
Pregnant or Nursing Females 19+ years 1000mg
When reading a food label, the calcium in that food item will most likely be displayed as a percent. This percent is based off the daily intake amount equating to 1000mg of calcium. It should also be noted that calcium is most effectively absorbed when taken in amounts of 500-600mg or less.2

Calcium side effects

Calcium has the potential to interact with several medications as well as alter normal bodily functions. Medications include:1

  • Antacids that contain aluminum
  • Antibiotics
  • Anti-seizure medications
  • Biophosphates
  • Blood pressure medications
  • Cholesterol-lowering medications
  • Calcipotriene (Dovenex)
  • Corticosteroids (prednisone)
  • Digoxin
  • Estrogens
  • Gentamicin
  • Sotalol (Betapace)
  • Thyroid hormone

Bodily function side effects include: constipation and an upset stomach, high doses of calcium may result in nausea, vomiting, loss of appetite, increased urination, kidney damage, confusion, and an irregular heart beat. Anyone with a history of kidney stones should not take a calcium supplement.

1Calcium -

2Calcium: What You Should Know -

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