We all know that calcium is an important nutrient for the health of our bones and teeth, but many people are not aware that calcium plays many other important roles in the body and is a vital mineral for a broad range of organs and body systems.
Calcium in the body is stored in the bones. When levels of calcium in the blood are low, calcium is taken from the bones to increase levels in the blood. Those with continually low calcium intakes will gradually lose calcium from the skeleton over time, leading to development of osteoporosis.
Calcium is essential for the function of the brain and nervous system. Nerves require calcium for the transmission of electrical signals through the body. Similarly, the heart requires calcium to keep the heart beating normally.
Calcium may also reduce the risk of some cancers – including colon and breast cancers, reduce the symptoms of premenstrual syndrome, and lower high blood pressure and levels of “bad” (LDL) cholesterol in the blood.
There are several forms of calcium used in dietary supplements. Calcium carbonate is one of the cheapest forms and provides the highest percentage of calcium in a supplement – but it is also one of the more difficult forms of calcium to absorb. Calcium citrate is more expensive, but is more absorbable, as is calcium aspartate.
Calcium absorption varies depending on the integrity and functioning of the gastrointestinal tract, food consumed with calcium, time of day calcium supplements are taken, and age of the person. Caffeine can impair the absorption of calcium, as can high-protein or high sugar foods, while dairy products enhance calcium absorption. Older people have more difficulty absorbing calcium due to decreased stomach acid production. If you know that you have low stomach acid, or if you are over the age of 50, you should take calcium supplements with food to support absorption. Also look for calcium in the form of calcium citrate or aspartate.
Calcium is an important supplement for everyone and prevention of osteoporosis through adequate development of bone density should begin as a child. As an adult woman, take 1,200 mg of calcium daily, increasing to 1,500 mg as you age if you are thin, small boned, post menopausal or are otherwise at risk for osteoporosis. Consider all sources of calcium in your diet as well, and speak to your doctor if you think you may need to supplement with higher levels of calcium.
Calcium carbonate supplements can impair the absorption of other nutrients in the body, including zinc. They may also reduce the absorption of prescription medications such as thyroid hormones.
Supplementation with excessive levels of calcium and vitamin D can lead to excess levels of calcium in the blood. Symptoms include headache, difficulty concentrating, high blood pressure, vomiting and constipation.