Vitamin E is a fat-soluble vitamin that protects the cell membranes (the outer layer of a cell) from free radical damage. Being fat-soluble, vitamin E is generally found in foods that contain fat. Vegetable oil, nuts, and whole grains are good sources of vitamin E. Since these foods — particularly oils and nuts — also provide fat calories, it is wise to choose sources of fat that will also have a positive impact on your blood cholesterol level and heart health. Some good choices include canola and safflower oil, almonds, nonhydrogenated margarine (with 0 grams of trans fat), wheat germ, whole wheat bread, and whole-grain cereals. Processed grains such as white flour and white bread are poor sources of vitamin E. Dark-green leafy vegetables are a low-fat, high-fiber source, although they are much lower in vitamin E content than the oily sources.
The RDA for vitamin E is 15 mg/day for adults, but it is commonly listed on supplements in IU (International Units). The safe upper limit is set at 1,500 IU, but in 2004, a review of 19 clinical trials found that taking a vitamin E supplement greater than or equal to 400 IU daily may increase the risk of death. The decision whether to take vitamin E supplements should therefore be made with care. It is considered safe to take a vitamin E supplement of up to 400 IU, but trying to get what you need from oils, nuts, whole grains, and green leafy vegetables is the preferred course of action.
The carotenoids and vitamin A promote a healthy mouth through their roles in collagen formation, antioxidant activity, and healthy production of the epithelial cells that line the oral cavity. Carotenoids are a group of phytochemicals (plant chemicals) called provitamins of vitamin A, which means they are converted to vitamin A in the body. By themselves, they also have individual antioxidant properties. The best-known carotenoid is beta-carotene. However, lycopene and lutein are also becoming notable for their possible roles in prostate and eye health, respectively. Carotenoids are actually the pigments that give orange-yellow fruits and vegetables their color. They are easily recognized in carrots, squash, pumpkin, sweet potato, apricots, mango, and peaches. Dark-green vegetables like spinach and kale are also packed with beta-carotene, but the color is masked by the green-colored chlorophyll. There is no RDA for beta-carotene or the other carotenoids, but consuming these vegetables is the best route to obtaining adequate vitamin A, as well as fiber and other nutrients. Carotenoids are also heat stable, so they are only minimally diminished by cooking.
Preformed vitamin A is found in animal products and certain fortified foods and does not need to be converted in the body like the provitamins. The RDA for vitamin A (including converted carotenoids) is 700 micrograms per day (µg/day) for women and 900 µg/day for men. Food sources of preformed vitamin A include liver, egg yolks, and dairy products. While the body needs some vitamin A, too much preformed vitamin A is very toxic and can cause liver damage, birth defects, and bone damage; chronic supplementation of only two or three times the RDA can have these effects. Food is unlikely to cause toxicity, but supplements can easily do so. Neither supplementation of beta-carotene nor preformed vitamin A is recommended unless a person is at risk for deficiency. Since liver and egg yolks are high in cholesterol, choosing low-fat or nonfat dairy products and filling your grocery cart with beta-carotene-rich green and orange produce is the way to get your daily vitamin A.
Fat and cholesterol
Several studies have shown an association between blood cholesterol levels and periodontitis. Another study found that dietary cholesterol intake (which raises blood cholesterol) worsened periodontitis in rats. A diet low in saturated fat (less than 7% of calories or, for most people, less than 15 grams per day), trans fat (less than 1% of total calories, which is 2 grams per day for a person eating 2,000 calories a day), and cholesterol (less than 200 mg/day) helps control blood cholesterol level, which has a positive impact on both oral health and the cardiovascular system.