Calcium fact sheet, FAQ and product listing page. This page contains everything you need to know about calcium.
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What is calcium?
Calcium is the most abundant mineral in our body and has multiple critical functions. Almost all of the calcium in our body is located in our bones and teeth and essentially works as a support structure. The 1% that is not located in our bones or teeth is found in our blood, muscles and in the fluid between cells. Long-term deficiency of calcium can cause osteoporosis (the occurrence in which bones deteriorate), making you much more susceptible to fractures. Ultimately, it's an important part of a healthy diet and must be taken regularly.
What foods contain calcium?
Milk, yogurt, and cheese are the main sources of calcium in the typical American diet. This may explain why some individuals are deficient in their calcium intake since most people do not consume the right quantities of these products. The US Department of Agriculture recommends that people get 2-3 servings of dairy products per day. A serving is approximately equal to a cup of milk, 8 oz of yogurt, 1.5 oz of natural cheese (Cheddar), and 2.0 oz of processed cheese (American).
What does calcium do?
A constant and consistent level of calcium should be maintained in your body fluid and tissues so that your vital body processes function efficiently. Your muscles rely on calcium to be able to contract. But calcium is not only vital to your muscles and blood vessels, it is also used during the secretion of hormones and enzymes, and is essential for the effective functioning of your nervous system.
The bones in the human body undertake continuous remodeling and restructuring, with constant reabsorption (breaking down of the bone). Calcium is deposited in your bones during this process and provides a stronger, more stable structure. Those not yet in their older years have a higher amount of bone formation with less breakdown, as opposed to aging adults (particularly women) for who bone breakdown exceeds its formation. This results in bone loss and increases the risk of acquiring osteoporosis.
Effects calcium has on performance:
- Increases bone density
- Enables efficient muscle contractions
Who can benefit from using calcium supplements?
Everybody should consume calcium supplements regardless of whether they are physically active or not. Calcium is good for the daily operations of your body.
Calcium is especially beneficial for weight lifters and the elderly. Weight lifters benefit from calcium by having improved muscle contractions, with a strong bone foundation that hopefully is resistant against bone breakages and fractures. The elderly need to consume calcium specifically because of their weakening bones as they age. Without enough calcium in your body, walking down a flight of stairs can cause a fractured bone.
Does calcium have any side effects?
Those taking certain medications should avoid calcium as it my interfere with the effectiveness of the drug. These medicines include:
- Antibiotics in tetracycline family
- Tiludronate disodium
- Anticonvulsants such as phenytoin
- Thiazide, type of diuretic
- Mineral oil or stimulant laxatives
- Aluminum or magnesium containing antacids
While taking too little calcium can result in a deficiency and garner unhealthy side effects, taking too much calcium can have adverse side effects as well. Negative conditions linked to high calcium intake consist of hypercalcemia, impaired kidney function, as well as decreased absorption of other minerals such as iron, zinc, and magnesium.
References:  Shils ME. Modern Nutrition in Health and Disease. 9th ed. Baltimore: Williams & Wilkins, 1999  Subar AF, Krebs-Smith SM, Cook A, Kahle LL. Dietary sources of nutrients among US adults. J Am Diet Assoc 1998;98:537-47.