The National Institutes of Health describes calcium as "the most plentiful mineral found in the human body." (see Reference 1) The majority of calcium within the body can be found in the teeth and bones, with nerve cells, soft tissues, and bodily fluids comprising the rest. Calcium is commonly found in dairy products and is best absorbed from dietary sources. Inadequate calcium intake can put you at risk for brittle bones and other health problems.
Function
The body uses calcium for multiple purposes "including building and maintaining bones and teeth, blood clotting, the transmission of nerve impulses and the regulation of the heart's rhythm," according to Harvard University's School of Public Health. (see Reference 2). A process called remodeling occurs within bone tissue continually throughout life. Remodeling occurs when bone is broken down and rebuilt over time. Calcium is a fundamental part of this process. As you age, an imbalance in this process could lead to a condition called osteoporosis. Osteoporosis can be defined as a weakening of the bones, according to the Centers for Disease Control and Prevention. (see Reference 3)
Sources
When you think of calcium you probably think about milk. Dairy products, such as milk, yogurt and cheese, are the most commonly recognized food source of calcium. The United States Department of Agriculture National Nutrient Database for Standard Reference provides a list of dietary sources of calcium including non-dairy sources. They include canned fish such as sardines, calcium-fortified products such as orange juice and cereals and dark green leafy vegetables including broccoli, spinach and bok choy. (see Reference 4)
Supplements
The National Academy of Sciences established recommended intake levels which are 1,000 milligrams of calcium per day for those age 19 to 50, 1,200 milligrams/day for those age 50 or over and 1,000 milligrams/day for pregnant or lactating adult women. (see Reference 2). Often, doctors will recommend calcium supplements to ensure patients meet the minimum recommended calcium intakes. National Institutes of Health, Office of Dietary Supplements provides information regarding the two main forms of calcium supplements, citrate and carbonate. (see Reference 5) Calcium citrate can be taken at any time during the day and does not require stomach acid for absorption, while carbonate must be taken with meals or snacks to utilize stomach acids for absorption and may cause gas, constipation and bloating. Regardless of the type, you should not take more than 600 mg at one time and should not exceed 1500 mg per day unless instructed otherwise by your physician.
Osteoporosis
Failure to consume adequate calcium throughout your lifetime is one factor that can contribute to increased risk of osteoporosis. The National Osteoporosis Foundation, NSF, defines osteoporosis as "a disease in which bones become fragile and more likely to break." NSF states that "85-90% of adult bone mass is acquired by age 18 in girls and 20 in boys." (see Reference 6) This information is crucial to parents of young children and young adults. Consuming adequate calcium, exercising and not smoking or drinking alcohol are all important in preventing this disease later in life.
Dangers of Excessive Consumption
Just as too little calcium can contribute to health problems, too much calcium can also be counterproductive. Large amounts of calcium over a long period of time can contribute to the development of kidney stones, according to the National Institutes of Health. (see Reference 1) Consuming large amounts of calcium, particularly in the form of dairy products, may contribute to the development of prostate and ovarian cancers according to Harvard University. A study conducted at the University, "found that men with the highest calcium intake---at least 2,000 milligrams a day---had nearly double the risk of developing fatal prostate cancer as those who had the lowest intake."
Expert Insight
Experts at the National Institutes of Health developed guidelines to ensure optimal calcium consumption and absorption for overall good health. (see Reference 7) Consume adequate amounts of calcium from food sources using supplements only if necessary to meet the required amounts as noted above. Attain adequate vitamin D levels via sunshine, fortified foods or supplements to increase absorption of calcium within the body. Lastly, be aware of your calcium intake on a daily basis, as a large percentage of Americans do not meet their daily requirements putting their bones at risk for breakage.
References
- The National Institutes of Health: Calcium in Diet
- Harvard School of Public Medicine: Calcium and Milk: What's Best for Your Bones and Health?
- Centers for Disease Control and Prevention: Calcium and Bone Health
- USDA: National Nutrient Database for Standard Reference
- Dietary Supplement Fact Sheet: Calcium
Member Comments