Sunny smiles start with…the sun!

Teeth and gums are a little like plants. They are photosensitive and can be affected by the sun's rays, according to Charles F. Hildebolt, a dentist and an associate professor of radiology at Washington University's Mallinckrodt Institute of Radiology.

In an article on, Hildebolt says sunlight is an important part of oral health. Like plants, our teeth and gums are "photosensitive." This means they react to sunlight. Just as certain sunrays are vital to healthy plants, they're vital to healthy teeth and gums.

"Calcium and vitamin D are important to oral health," he says. "The best way to get calcium is through the diet, but we need vitamin D to regulate calcium, and it's hard to eat enough foods rich in vitamin D to meet that need. The best source of vitamin D is sunshine."

Vitamin D controls how our bodies process calcium. Even if our bodies store enough calcium, we need vitamin D to keep the right balance of calcium in our bones and blood. These bones include our teeth and jaws; vitamin D helps get the calcium to them.

Without vitamin D, the chances for gum disease greatly increase. Low vitamin D levels open the door for more cytokines, which are proteins that fuel irritation and infection. This is also called "inflammation." And gum disease can lead to much bigger problems.

"Periodontal (gum) disease is an inflammatory process in which cytokine levels are increased," says Hildebolt. "You can actually think of the disease as an overreaction to bacteria in the mouth that causes damage to the bone and the soft tissues that support the teeth."

Fortunately, sunshine helps our bodies "top up" their vitamin D levels.

Of course, we all know too much sunshine can be dangerous. But experts generally agree that 10 minutes of sun a day is enough to help our bodies make vitamin D. In addition to healthy gums, teeth, and bones, vitamin D and calcium also lower the risk for rheumatoid arthritis, cardiovascular disease, and diabetes.

Do people who live in sunnier places have fewer cavities?

There's a very interesting article by the Vitamin D Council about a range of studies linking the numbers of U.S. dental caries, or cavities, with U.S. places that have more or fewer sunny days each year.

The first study goes back to the 1800s. It looked at records of the draft for the U.S. Civil War. It says that eight of every 1,000 men in Kentucky were rejected for lost teeth. This is compared to 25 of every 1,000 men in New England.

In another study, authors found that people living in the sunny west (3,000 hours of sunlight per year) had half as many cavities as those in the much-less-sunny Northeast (fewer than 2,200 hours of sunlight per year).

Many other studies in the United States and the British Isles seem to support the idea that "sunnier places equal fewer cavities."

So along with good nutrition and regular and proper brushing and flossing, think about adding 10 minutes of daily sunshine to your smile!

About the Author:

Renée Melton