After years of whole grains being relegated to niche markets and vegetarian recipes, these fiber-based foods have enjoyed a surge in popularity. Propelling this move has been the publication of study after study showing the benefits of whole-grain foods such as oatmeal, brown rice, muesli, and millet. These benefits range from heart health and weight loss to better blood-sugar control.
Now, an international team of scientists has turned up yet another advantage: healthier gums and teeth.
Anwar T. Merchant of McMaster University in Hamilton, Ontario and his colleagues knew that poor blood-sugar control had been linked to increased risk of chronic periodontitis—gum disease accompanied by a gradual loss of the bone that anchors teeth in place. Some 30 percent of adults over the age of 30 have this disease, a leading cause of tooth loss. With several new studies suggesting that whole grains slow the breakdown of starches into blood sugar (SN: 4/8/00, p. 236), his group reasoned that whole grains might help protect teeth.
To find out, they turned to the all-male Health Professionals Follow-up Study, a long-running diet-and-health study administered by the Harvard School of Public Health. Begun 2 decades ago, the study includes periodic surveys of 51,529 recruits for data on lifestyle factors and disease in this group of U.S. dentists, veterinarians, pharmacists, optometrists, osteopath physicians, and podiatrists. After excluding men who began the study with periodontitis, diabetes, heart disease, or a history of stroke, the researchers were left with some 34,000 individuals. Extensive dietary histories, collected every 4 years, were then correlated with any subsequent reported diagnosis of periodontal disease.
In this group of fairly health-savvy individuals, Merchant’s team found a strong correlation between whole grains and the gum disease. Those eating the most whole-grain foods—typically 3.4 servings per day—were 23 percent less likely to develop periodontitis than were those who averaged a mere one-third of a serving per day.
Because most whole grains come from cereals, the researchers also probed for any confirmatory link between other types of fiber and periodontitis. Here, men consuming the most cereal fiber—some 10 servings per day—were 15 percent less likely to develop the gum disease than were those in the lowest consumption group, which consumed just 2.7 servings of cereal fiber per day.
By contrast, Merchant’s team found no link between periodontitis risk and total dietary fiber, fiber consumed from fruit, or vegetable fiber.
The mechanism for whole grains’ tooth protection isn’t certain. Merchant points to reports indicating that by reducing blood sugar, whole grains can limit the formation of advanced glycation end products (AGEs), compounds that form when sugar-protein pairings in the body begin to degrade or rearrange their building blocks. AGEs can play a role in arterial wall hardening, contribute to blood vessel damage in the kidneys and eyes, and even to complications associated with diabetes.
In general, Merchant says, in the mouth, AGEs deposit in soft tissues surrounding teeth, predominantly in the gums. There, they trigger inflammation, which sets off the production of a cascade of biochemicals that ultimately cause the body to eat away at the bone holding teeth in place.
The new whole-grain findings, though still preliminary, are quite encouraging, Merchant told Science News Online, because they “point to a lifestyle factor—something over which a person has control—that can reduce periodontitis risk.”
Less encouraging news . . .
Last year, the U.S. Department of Agriculture revised the traditional Food Pyramid that children had been taught in grade school for the previous half-century. The new iteration, called MyPyramid (see http://www.mypyramid.gov/), encourages people to personalize the dietary guidance based on their age, caloric intake, and gender. For instance, it recommends that teenage boys eat foods containing at least 3.5 ounces of whole-grains per day, and girls 3 ounces. Most women should also eat at least 3 ounces of whole grains per day, MyPyramid says, and men 3 to 4 ounces, with 20-somethings needing the most.
Where would one find those whole grains? Charts prepared by the MyPyramid program show, for example, that 3 ounces could be derived by eating a trio of 4.5-inch diameter whole-wheat pancakes, 2.25 cups of popcorn, 1 large whole-grain muffin, or 1.5 cups of wild rice.
That said, most people don’t down nearly as many whole-grain foods as nutritionists contend they should.
It’s something that Linda E. Cleveland of the U.S. Department of Agriculture in Beltsville, Md. and her colleagues gleaned when they surveyed daily whole-grain consumption among more than 9,300 adults that were a representative cross-section of the nation. Overall, these adults averaged about 6.7 servings of grain products a day—but typically only 15 percent of the total came from whole grains. Moreover, this survey, published 6 years ago, showed that only 8 percent of adults consumed the recommended minimum 3 ounces of whole grains per day.
Judi F. Adams and Alta Engstrom of the Wheat Foods Council in Parker, Colo., have studied surveys to determine why people don’t reach for more whole-grain offerings. A primary reason: Consumers haven’t yet gotten the message that diets rich in these foods appear to reduce one’s risk of developing any of several costly, chronic diseases. In one survey, they found, when participants were asked which foods might reduce risk of disease, broccoli, orange juice, garlic, fish oil, leafy vegetables, and milk all made the list. Even fiber was recognized as a beneficial nutrient by 7 percent of those questioned—but “whole grains were never mentioned,” Adams and Engstrom reported in 2000 as part of the proceedings of a fiber symposium.
In addition, they note that whole grains don’t carry the same siren appeal as, say, chocolate, or strawberries. This means that cooks who want to boost the whole-grain component of their family’s diet may need to be a little creative, such as surreptitiously adding barley, oats, or brown rice to casseroles, chili, and stews. They might also try serving a whole-grain salad, such as the bulgur-wheat-based tabbouleh (see below), in place of a bowl of mixed greens. Or they might offer whole-wheat French toast or whole-grain bagels for breakfast.
If these items still aren’t to your family’s liking, General Mills and other manufacturers have been rolling out reformulated, whole-grain versions of their popular national-brand cereals, such as Trix and Cocoa Puffs.
Last month, General Mills even unveiled a new flour: DuruWhite. It’s whiter than most other whole-grain flours, which means it bakes up into something that’s moister and approximates the white bread that most U.S. baby boomers grew up on.
The flour, made from whole durum wheat—a type that has typically gone into pasta—permits the production of breads with up to an ounce of whole grain per serving. Alas, General Mills spokeswoman Kirstie Foster points out, this flour is currently being marketed only to commercial bakeries.
A whole grain salad
The American Institute for Cancer Research (AICR), which offers the recipe below, claims that the combination of nutty bulgur mixed with wonderfully ripe tomatoes, zucchini, and lots of fresh mint “is sensational. The mint adds a bright, unexpected note, while the olive oil and lemon juice add the finishing touches.” Tabbouleh is best served cold, either as a main dish or side. AICR notes that this whole-grain salad “is loaded with cancer-protective phytochemicals, vitamin E, niacin, zinc, iron and magnesium.” There are many variations for making tabbouleh, so feel free to customize the ingredients to your palate. Some variations include increasing the bulgur, replacing the mint with basil, or leaving these greens out altogether. Personally, I prefer recipes that add an extra cup or so of finely minced parsley or cilantro. Tabbouleh can be eaten on crackers, pita chips, or mounded on romaine lettuce leaves.
- 1/2 cup bulgur, cooked according to package directions or until tender
- 2/3 cup chopped mint, lightly packed
- 12 cherry tomatoes, halved (or 6 large, quartered)
- 1 small zucchini, finely diced
- 2 Tbsp. fresh lemon juice
- 2 Tbsp. extra virgin olive oil
- Salt and freshly ground black pepper, to taste
Drain the cooked bulgur well and place it in a medium-size bowl. Add the mint, tomatoes and zucchini. Toss it with a fork to combine. Mix in the lemon juice and oil. Season to taste with salt and pepper. This salad keeps in the refrigerator, tightly covered, for 1 day.
Cooking Options: use couscous instead of bulgur for a shorter cooking time. And if you have a food processor, you can use that to chop the mint. You can also use chopped tomatoes instead of cherry tomatoes.
Makes 4 servings. Per serving: 137 calories, 7 g fat (1 g saturated fat), 17 g carbohydrates, 3 g protein, 4 g dietary fiber, 11 mg sodium.