Oh, no — not another preachy article on calcium and osteoporosis prevention! Start the blah, blah here. Nod your head and vow to pick up some supplements at the store, maybe force down a glass of milk. Make a mental note: strong bones are good. Now you can move onto the fashion section without guilt.
Not so fast. There’s much more to this mighty mineral than most of us know. While we have connected the dots between calcium and preventing bone loss, some fine-tuning of that understanding, as well as new discoveries relating to calcium’s effect on overall health, is begging for your attention. Calcium builds strong bones.
Most people know a diet rich in calcium helps build strong bones and teeth. However, reaping the biggest bone-building benefits is all in the timing. Calcium is deposited in bones until about age 30; that’s when women and men begin to slowly lose bone mass.
And that’s where timing comes into play. A study by the American Academy of Pediatrics says that children and adolescents are not getting enough calcium. It’s important to stock the bones of our youth with calcium to prepare them for the gradual depletion they’ll experience later in life.
Women, especially those who have gone through menopause, hear a lot about osteoporosis –- a disease that causes your bones to become so thin they can break easily. Whether you develop osteoporosis or loss of bone mass (osteopenia) depends on the thickness of your bones early in life, as well as family history, health, diet and physical activity later in life.
So just pop a Tums® or give your kids a multivitamin and you’re all protected, right? University of Texas Health Science Center nutrition instructor and registered dietitian Sue Cunningham doesn’t recommend going right to supplements. “I’ve always seen it as risky, perhaps even unethical, to recommend a supplement if you don’t know how much patients are getting through their diet,” says Cunningham. She cites a number of reasons for advocating dietary sources of calcium before supplements:
You can’t overload on dietary calcium. However, an increase in elemental calcium has been linked to kidney stones.
Your body can’t absorb more than 500 mg of calcium at a time. Any excess is literally going down the drain — perhaps not the best use of your money or kidneys.
Vitamin D must be taken with calcium in order for your body to absorb it properly. The perfect combo is readily available in milk.
Supplements are not regulated. Buyer, beware –- some calcium supplements are made from oyster shells, which can be high in lead.
Supplements can be expensive. Everyone has to eat. Why not simplify your life and make calcium-rich food choices, rather than having to remember to buy and consume a supplement?
Cunningham also recommends avoiding soda and caffeinated beverages. “Not only does it contain empty calories, but soda has been shown to draw small amounts of calcium out of the bones, and caffeine has been linked to osteoporosis,” she says. “But more importantly, you’re drinking something in place of milk or orange juice, two very good sources of calcium.”
Calcium from dairy products may speed weight loss
Maybe you’ve noticed the latest claims on yogurt and cheese labels pointing to studies showing dairy products can help you lose more weight as part of a high-calcium, reduced- calorie diet. America’s milk producers are beating the drum, saying that consuming calcium from low-fat or fat-free milk could help you lose more weight than simply reducing calories. Dr. Phil is on board, sporting a milk mustache in “Got Milk?” ads where he implores us to “get real about losing weight.” They even go so far as suggesting 24 ounces every 24 hours — and just as milk prices are on the rise!
Truth in advertising? Actually, yes. Although calories still count, a study supported by the National Dairy Council appearing in the April 2004 issue of Obesity Research showed that obese adults who ate a high-dairy diet lost significantly more weight and fat than those who ate a low-dairy diet containing the same number of calories.
“Too many people drop dairy from their diets when they try to lose weight,” says researcher Michael Zemel, Ph.D., professor of nutrition and medicine at the University of Tennessee in Knoxville. “They’re shooting themselves in the foot when they do that. Dairy products contain literally hundreds of compounds that have a positive effect on human health and enhance the fat-burning machinery,” he explains.
“When we cut dairy products, we send the body a signal to make more fat,” says Zemel. “When your body is deprived of calcium, it begins conserving calcium. That mechanism prompts your body to produce higher levels of a hormone called calcitriol, and that triggers an increased production of fat cells.”
High levels of calcitriol “tell” fat cells to store themselves in the body and to expand, he says. “So you’re getting bigger, fatter fat cells. And a lot of big fat cells makes for a big, fat person.” Extra calcium in your diet suppresses this hormone, he says. Your body breaks down more fat, and fat cells become leaner, trimmer. A high-dairy diet can boost weight loss by about 70 percent, says Zemel.
However, it doesn’t mean that just eating more dairy can help you lose weight. Calories are still the bottom line. What matters is the composition of those calories. Having more of them come from calcium-rich foods is associated with lower weight and lower body fat.
Unfortunately, premium ice cream was not one of the dairy choices in the study. Researchers said participants were free to choose from fat-free, low-fat and regular milk, cheese and yogurt. They typically picked fat-free and low-fat milk and yogurt and regular cheeses, while keeping their overall fat intake the same. Serving sizes were 8 ounces, or a cup, for milk and yogurt and 1.5 ounces of hard cheese (about the size of six dice) or 2 ounces of processed cheese, such as two slices of American cheese.
Zemel says the study also showed that eating three to four servings of dairy products a day is more effective at enhancing weight loss efforts than calcium supplementation alone with pills or calcium-fortified foods.
This study is unique because it indicates that it’s more than just the calcium that helps shed pounds — it’s that the calcium is from a dairy source. Previous studies already support that people on a calcium-rich diet are more successful at losing weight. “Calcium is a critical factor in controlling what your body does with calories, and dairy is an even more critical factor,” says Zemel. “Without changing how many calories we take away, we can alter how much weight and fat you lose.”
Calcium may reduce symptoms of PMS
Premenstrual Syndrome (PMS) affects four out of 10 women of childbearing age. The most common symptoms of irritability, muscle pains, bloating and backache may be accompanied by cravings for salt and sugary foods, especially chocolate. Sound familiar? There’s compelling research that indicates these cravings and symptoms may indicate a nutritional deficiency of calcium and magnesium.
A 1998 double-blind placebo study conducted by Susan Thys-Jacob, M.D., at Columbia University College of Physicians and Surgeons found that symptoms of PMS lessened with calcium supplementation of 1,200 mg per day. In the study, 466 women with PMS from ages 18 to 45 participated. Half of the women received calcium carbonate supplements; the other half received a placebo. She found that after two or three menstrual cycles, patients who received calcium reported significantly less discomfort associated with almost all reported PMS symptoms. For example, the calcium-takers noted a 45-percent decrease in mood symptoms such as depression and sadness. The placebo-takers noted a 28-percent decrease. Food cravings and pain symptoms decreased 54 percent among those taking calcium compared to the placebo group, who reported a 34-percent reduction in food cravings and a 15-percent increase in pain.
The researchers noted that calcium is equally effective, cheaper and without the side effects of the antidepressant drug Prozac and the anti-anxiety drug Xanax.
Dr. Thys-Jacob says women should first try to consume more calcium-rich foods in their diets. If that doesn’t alleviate PMS symptoms, then supplements may be appropriate. She also noted women should avoid products that cause excessive excretion of calcium, such as colas.
Consistency is important. If you regularly consume calcium-rich foods that add up to about 1,200 mg per day, such as one cup each of milk, low-fat yogurt and fortified orange juice, symptoms of PMS may be significantly lessened or possibly eradicated without the side effects or expense of medications.
More calcium benefits
Reduces risk of stroke — According to a 1999 Harvard study of 85,764 women, ages 35-59 and followed over 14 years, an increase in calcium intake can cut the risk of stroke in middle-aged women. Although the study researchers are not clear about exactly how calcium protects against stroke, the study revealed women taking at least 400 mg of calcium in supplement form had a 12-percent lower risk of ischemic stroke (the type caused by plaque buildup in blood vessel walls) than did those women who took no supplements at all. Dietary calcium was also found to be protective, especially calcium from dairy foods. Caution: The study showed calcium intakes greater than 600 mg a day did not significantly boost protection against stroke. More is not always better.
May lower blood pressure — Dietary calcium has been linked to reducing the risk of developing high blood pressure, especially in pregnant women. The Recommended Dietary Allowance (RDA) guidelines suggest 800-1,200 mg of calcium per day for general overall health.
Lowers risk of some types of colon cancer — Results from about 88,000 women in the Nurses’ Health Study and 47,000 men in the Health Professionals’ Follow-Up Study found people who had a higher calcium intake had a lower risk of left-sided colon cancer. Men and women who consumed 700 to 800 mg of calcium in their diets each day had a 40- to 50-percent lower risk of left-sided colon cancer compared to those who received less than 500 mg of calcium a day. The authors suggest that calcium reduces colon cancer risk by slowing cell growth –- a process that, when uncontrolled, can lead to cancer.
Now that you’re acquainted with myriad health benefits calcium provides, how do you know how much calcium, and in what form, you and your family should consume? First, consult your family physician. UTHSCSA nutritionist Sue Cunningham also recommends checking your health insurance to see if it covers medical nutrition therapy or dietetic counseling. Many insurers now consider prevention cost effective. As a result, you may be able to get a complete analysis of your diet by an expert, with recommendations that fit your individual situation best.
Caution: Information in this article should not be considered medical advice. Consult your physician before making dietary or supplement decisions.
Sources: Whole Health MD, WebMD, Medical College of Wisconsin, National Dairy Council, Mayo Clinic and Stonyfield Farm.
Author: Kelly A. Goff