As new evidence points to the elevated role of calcium in preventing disease, it makes sense to get enough of this vital nutrient each day, especially as mid-life approaches. Experts say there is literally no body system that doesn't benefit from a healthy dose. Here's how it stacks up:
Calcium and Weight Loss:
When Dr. Robert Heaney, a calcium expert at Creighton University in Omaha, recently examined the health records of 575 women, he was astonished at the results. "We were looking at mid-life weight gain and found that women with the highest calcium intakes didn't gain weight and those with the lowest did," Dr. Heaney said.
Similarly, at the University of Tennessee, Michael Zemel, Ph.D., reported that because calcium plays a key role in metabolic disorders linked to obesity and insulin resistance, a diet low in calcium literally stockpiles fat cells while higher calcium diets depletes them. Dr. Zemel discovered that a high calcium diet released a hormone which sends signals that are read by the body's fat cells to lose weight.
A two-year Purdue University study in West Lafayette, Ind. that involved 54 women ages 18 to 31, found that women with a daily intake of at least 780 milligrams of calcium showed no increase in body fat or lost body fat mass during a two-year period. Women who averaged less than 780 milligrams of calcium gained weight during the same period.
Both exercisers and couch potatoes seemed to benefit unless they consumed more than 1,900 calories daily. All researchers said that dining on calcium-rich dairy products such as milk, cheese and yogurt achieved greater weight loss than leafy green vegetables, nuts, beans and supplements.
Calcium and Premenstrual Syndrome:
Susan Thys-Jacobs, an endocrinologist at St. Luke-Roosevelt Hospital's, has found that calcium supplementation can relieve the physical and emotional toll of PMS by almost 50%. At least half of the 497 women she studied who took 1,200 mg. of calcium supplements experienced fewer mood swings, depression/sadness, anxiety/nervousness; breast tenderness, bloating and other aches and pains. The U.S. Department of Agriculture's Human Nutrition Research Center in Grand Forks, N.D. reported similar results after studying 10 women with PMS who spent half the study period on a daily diet containing 600 mg. of calcium, the other half upped to1300 mg. Women on the high calcium diet were less irritable, weepy, and depressed and averted backaches, cramping, and bloating.
Calcium and Blood Pressure:
In some people, an increase in calcium consumption can help control blood pressure without anti-hypertensive medication. A 13-year study by James Dwyer at the University of Southern California School of Medicine found that consuming 1300 milligrams of calcium a day reduced hypertension risk by 12 percent compared to only 300 mg. a day, while subjects under age 40 reduced their risk by up to 25 percent. Dr. Lawrence Resnick, a professor of medicine at Cornell University Medical Center Hypertension Center, emphasizes that the benefits are most pronounced in hypertensives who are salt-sensitive, such as African Americans.
Calcium and Cholesterol:
Dr. Margo Denke, associate professor of internal medicine at the Center for Human Nutrition at the University of Texas Southwestern Medical Center in Dallas found that a high-calcium regimen reduced levels of total cholesterol by six percent and slashed "bad" LDL cholesterol by 11 percent. So-called "good" HDL cholesterol levels remained unchanged.
Calcium and Stroke Prevention:
A 1999 Harvard study reported that calcium supplementation protects against stroke in middle-aged women. In the ongoing Nurses' Health Study, 85,764 women, ages 35 to 59, reported that the mineral was tied to a 32% lower risk of stroke among those with the highest intake of the mineral. Women taking at least 400 mg of calcium supplements had a 12% lower risk of ischemic stroke (the type caused by plaque buildup in blood vessel walls). Dietary calcium, especially in dairy foods, reportedly reduced stroke risk, as did potassium.
Calcium and Osteoporosis:
Osteoporosis strikes more than seven million Americans, mostly women, with another 17 million at serious risk of developing fragile bones that easily collapse, a crippling curving of the spine, and hip fractures. Research shows that boosting calcium intake can halt bone loss, especially when combined with vitamin D, which enhances its absorption.
Calcium and Colon Cancer:
Calcium may protect against growths that become malignant in those prone to colorectal cancer. Dr. Martin Lipkin, a professor of medicine at Cornell University, who first discovered the link between calcium and colorectal cancer, stresses that both calcium-rich foods and calcium supplements will produce the same beneficial effects.
Calcium and Pregnancy:
According to Barbara Levine, director of the human nutrition program at the Rockefeller University, calcium supplements can help ensure the health of the fetus and improve bone mass of the mother. In a study of hypertensive women, Levine found that adequate calcium levels and Vitamin D improved pregnancy outcomes.