If you have tender, swollen gums that bleed when you brush or floss, your diet may be to blame. A study published in the August 2000 issue of the Journal of Periodontology found that people who don't get at least 60 milligrams of vitamin C per day (the minimum daily amount recommended for adults over age fifteen) have higher rates of periodontal disease than those who get less than this amount.

In another study, to measure the effects of vitamin C deficiency on gum health, researchers at the University of California San Francisco School of Dentistry fed eleven men rotating diets for fourteen weeks. The diet purposely excluded all fruits and vegetables, which are typically high in vitamin C. During some weeks, the men were given a vitamin C supplement dissolved in grape juice. At the end of the study, researchers found that the men's gums bled more during the weeks that they received no vitamin C. When they received the vitamin C supplement, their gums bled less.

How does vitamin C help to keep your gums healthy?

Simply put, your body needs adequate vitamin C to strengthen your bones and blood vessels, to anchor your teeth into your gums, and to form the intracellular cement your body needs for growth, tissue repair and wound healing. Vitamin C can also strengthen weakened gum tissue and make it more resistant to penetration by disease-causing bacteria.

When your gums bleed when you brush or floss, and are irritated, tender, swollen or red, you may have early gum disease, called gingivitis. This is caused by food particles and bacteria left on your teeth combining to form plaque, which hardens on your teeth and becomes tartar (also called calculus). The bacteria in plaque infect your gums, and cause them to pull back and away from your teeth (recede), forming pockets where even more bacteria can hide and reproduce. If it's not taken care of, this infection starts attacking the roots of your teeth and the bone in your jaw, causing irreversible damage which can lead to bone loss.

Foods high in vitamin C

Many fruits and vegetables are great sources of vitamin C, but since exposure to oxygen destroys vitamin C in foods, it's important that you eat them soon after they've been cut open. For example, a sliced cantaloupe left uncovered in the refrigerator loses 35 percent of its vitamin C in less than twenty-four hours.

Following are foods that are high in vitamin C:

• red and green peppers
• guavas, papayas and mangoes
• broccoli, red cabbage and cauliflower
• strawberries and raspberries
• spinach and tomatoes
• oysters
• soybeans
• cantaloupe and honeydew