Vitamin Supplements

Calcium and Osteoporosis

Osteoporosis is a disease of declining bone mass, or density (the amount of material contained in the bone). Bone mass normally accumulates until a person is about age 25 and begins to deteriorate around ages 50 to 60 years; the bones then become weaker and much more vulnerable to fractures. Women experience a particularly rapid decrease in bone mass because of their sharp decline in estrogen levels during menopause. Read the rest of this entry »

Calcium, the most abundant mineral in the human body, makes up about 2 percent of your body weight. About 99 percent of that is in the bones and teeth; the rest is in tissues and in the body fluids that bathe the cells. In order for your body to absorb the calcium from your diet and make use of it, you also need sufficient amounts of vitamin D.

A mechanism built into your body keeps the levels of calcium in your blood balanced—at sufficient but not excessive amounts. When calcium levels begin to rise too high, the thyroid manufactures a hormone called calcitonin, which draws excess calcium from the blood and deposits it in the bones; urine and feces also carry extra calcium out of the body. Conversely, when calcium levels dip too low, the parathyroid produces a hormone that pulls stored calcium from the bones and sends it to the blood. If the latter process goes on for too long, the bones are depleted of the calcium they need and become thin and weak. Read the rest of this entry »