Date: October 1, 2011
No doubt, you know getting plenty of calcium is one of the best ways to ward off bone-thinning osteoporosis later in life. But that's not all. The latest research shows there are at least five new reasons for the recommended daily intake (or more) of this mighty mineral, which is 1,000 mg for adults up through age 50, including pregnant or nursing women. Read on to find out how this super nutrient benefits you besides helping build bone.
1. Combating colon cancer
Among women in the U.S., colon cancer is one of the three most common cancers. Research shows, however, that a diet rich in calcium may help prevent this invasive disease. A study in the Journal of the National Cancer Institute, for example, which pooled preliminary data from 10 studies in five countries involving 534,536 participants, found that those who consumed the most milk had the lowest risk of colon cancer.
The theory: Without adequate calcium, bile and fatty acids — natural byproducts of digestion — can irritate the colon, causing a constant state of cell repair that's an invitation for cells to become cancerous. The more cells regenerate, the more their DNA has the opportunity to be exposed to toxic agents that can cause them to divide too rapidly, explains calcium researcher, Dr. Peter R. Holt, professor of medicine at Columbia University in New York City. Calcium, however, binds with these pesky colon acids, preventing them from doing their damage.
2. Downsizing PMS
With more calcium in your diet, you're apt to suffer less from the mood swings, headaches, irritability and anxiety associated with your period. A major study showed that a daily dose of 1,200 to 1,500 mg of calcium can reduce by half those classic signs of your period approaching.
"Premenstrual symptoms indicate that a woman has an underlying calcium deficiency," says study researcher Dr. Susan Thys-Jacobs, director of the Metabolic Bone Center at St. Luke's-Roosevelt Hospital in New York City. With plenty of calcium in tow, you'll feel better at PMS time. You'll also help prevent osteoporosis since the same hormones instigate both conditions. "If you suffer from PMS, you're also probably losing bone," Thys-Jacobs says.
3. Preventing high blood pressure
Typically called "the silent killer" because it's often symptomless until it's too late, high blood pressure can lead to heart disease, the leading cause of death for both men and women in the U.S. High blood pressure is also a formidable threat if it develops during pregnancy, a condition called preeclampsia. Calcium from dairy products, however, in combination with a balanced, low-fat diet, may help keep blood pressure in check.
In a major government study called DASH (Dietary Approaches to Stop Hypertension), "calcium was one of several nutrients that lowered blood pressure," says Eva Obarzanek, a researcher with the National Heart, Lung and Blood Institute. In fact, out of the DASH study came DASH-style diets — eating plans that are rich in fruits and vegetables, moderate in low-fat or nonfat dairy foods, and low in sodium and sweets. A typical DASH-style diet, which is widely distributed to high blood pressure patients in the U.S., recommends two to three servings a day of low-fat or nonfat calcium-rich dairy foods such as skim milk, nonfat yogurt and low-fat cheese.
4. Conquering kidney stones
If you've ever had a kidney stone, you know those minute collections of minerals that form in the kidneys can cause excruciating pain when they pass through the urinary tract and out of the body. Most kidney stones are made from calcium and oxalate, a salt-like substance found in foods such as beets, spinach, rhubarb and nuts. Your body also makes its own steady oxalate supply. Normally, calcium and oxalate remain dissolved and are excreted in the urine. But stones can form when calcium and oxalate become too concentrated in the kidneys, becoming a solid not unlike sugar settling to the bottom of your coffee cup.
A 12-year Harvard University study involving more than 90,000 women, however, found that those with the highest calcium intake had the lowest risk of kidney stones. The theory? Calcium binds with oxalate during digestion, canceling out the possibility that stones will form.
A caveat: The same study also showed that taking calcium supplements without food may actually increase the likelihood that kidney stones will form in some people.
5. Beating breast cancer
And finally, calcium may also help reduce the risk of breast cancer, especially if you drink milk. A Finnish study involving more than 4,600 women concluded that those who drank roughly three 8-ounce glasses of milk a day had the lowest risk of breast cancer compared to those who didn't. Researchers suspect that calcium, as well as several other components in milk, such as conjugated linoleic acid, may have potent breast cancer-fighting properties.
Sandra Gordon is a mother of two who frequently writes about health topics.