Perfect smile: support healthy teeth with calcium

Better Nutrition, Nov, 2003 by Perry O'Donnell

What role, if any, does diet play in dental health? If you drank plenty of milk as a child and continue to brush, floss and see your dentist regularly, isn't that enough?

Evidently not. While scientific research into the effect of diet on the condition of your teeth has been scarce, the role of dietary calcium--for adults as well as children--is increasingly taken for granted by health care practitioners who see real live patients. Now, a new study, conducted by the University of Iowa and published in the September 2003 issue of Pediatrics, underscores calcium's importance, confirming what most dentists have suspected for years.

What you eat affects your dental health, and getting enough dietary calcium, as a child and as an adult, is as important in many ways as limiting your intake of sugar.

It's high time people got the message. Despite easy access to unprecedented volumes of information, not to mention motorized toothbrushes, kid-friendly toothpastes and fluoridated water, children continue to develop cavities, in part because of what they eat--of, more precisely--what they drink. The researchers found that the children who had the most cavities at the end of the 5-year study were also those who reported drinking more soft drinks and powdered beverages such as Kool-Aid, most of which are loaded with sugar.

But even the youngsters who drank mostly fruit juices continued to develop more cavities than researchers would have guessed.

That's probably because most juices are sugar-heavy too. "If you talk to any pediatric dentist who sees kids who are slugging down juice 24/7, [those kids are] going to have rotten teeth," says lead researcher Teresa A. Marshall, PhD, RD, of the University of Iowa's College of Dentistry.

When sugar--from soft drinks, fruit juices or any other source--hits the tooth's surface, its interaction with bacteria in the mouth produces an acid that erodes the enamel. The stronger the enamel, the more resistant it is to tooth decay, which is why it is important for children to drink plenty of milk, the source of calcium that comes most readily to mind. Other sources include green leafy vegetables, rice, beans, almonds and dietary supplements.

"Calcium is extremely important for the development of teeth in children," says Ken Fieldston, DDS, a dentist in Cresskill, New Jersey. "The interesting question, however, is whether calcium is also important for the dental health of grownups, and the evidence so far suggests that it makes a contribution, even if we can't yet show cause and effect."

But calcium is known to help prevent osteoporosis, and research may someday establish beyond a doubt the connection between osteoporosis and dental health. "With severe osteoporosis, you often see periodontal [gum] disease, and it seems likely that a lack of calcium contributes to this condition," Fieldston says. At issue is the health of the basal, or jaw, bone, in which the teeth grow, and that of the alveolar bone, which forms around teeth when they erupt.

Two studies conducted at the University of Buffalo School of Dental Medicine and presented at the 1998 meeting of the International Association for Dental Research found that those who had too little calcium and low levels of vitamin C as young children ran nearly twice the risk of developing periodontal disease as adults than those who had higher levels. The studies showed not only the importance of calcium in warding off periodontal disease but also the importance of diet itself. "It is no longer enough to tell children to brush their teeth, floss and see their dentist," said Sara Grossi, DDS, a senior research scientist at the University of Buffalo. "Diet plays a larger role than we anticipated."

Researchers were also surprised to discover that low calcium intake in participants 20-39 years of age nearly doubled their risk of periodontal disease, which the American Academy of Periodontology names as the leading cause of tooth loss in adults 35 and older. "We never knew people so young were at risk of gum disease and of losing bone around their teeth," Grossi said.

A more recent University of Buffalo study, published in the August 2000 issue of Journal of Periodontology, found that adults who consume at least three servings of calcium per day--about 1,500 milligrams (mg)--have significantly lower rates of periodontal disease, probably because calcium strengthens the alveolar bone. "Warding off periodontal disease is one more good reason to make an effort to consume enough calcium," says Janet Helm, a registered dietitian and spokesperson for the American Dietetic Association.

A February 2003 study arrives at similar conclusions. Scientists at the Calcium and Bone Metabolism Laboratory at Tufts University in Boston found tooth loss can be minimized by getting recommended dietary allowances of calcium (1,000-1,200 mg) and vitamin D (400-600 international units). (Vitamin D is necessary for the absorption of calcium, which is why milk tends to be fortified with it.)