Soluble. Insoluble. Viscous. Fermentable. Fiber's many forms can confuse the most ardent health nut and even nutrition professionals debate the precise benefits of each type. Thankfully, then, a series of recent studies have lifted one clear message above the noise: Don't fret the categories, but focus on total fiber; getting lots of it from unprocessed plants will lower your risk of health problems well into your golden years.
That message has been taken to task by a French study. When researchers examining close to 6,000 people associated fiber intake with high blood pressure, cholesterol and other risk factors for cardiovascular disease, they came up with a complex latticework of benefits by type and source of fiber. For example, fiber from cereals was linked to lower body mass index and blood pressure while fiber from dried fruit and nuts was associated with a lower waist-to-hip ratio.
With two exceptions, this type of breakdown is far too picky, says Texas A&M University nutrition scientist Joanne Lupton, who chaired a National Academy of Sciences panel on dietary reference intakes for fiber. "The more I read the studies," she said, "the more it really is quite clear to me that it is fiber from the diet-total fiber-that's beneficial."
Observational studies on cardiovascular disease support Lupton's claim. The massive Nurses' Health Study and Health Professionals Follow-up Study, among others, found that adults who consumed the most total fiber, near the recommended 25 grams per day for women and 38 grams for men (double what typical Americans consume) are much less likely to suffer heart problems. "Collectively, it's about a 30 percent risk reduction in heart disease," Lupton says.
The big disappointment, however, is that current research has found no connection between fiber and colorectal cancer. That news undercuts the safety net of many people with a family history of colon cancer since doctors, depending upon intuition and encouraging animal studies, have long recommended high-fiber diets. Still, there may be some as-yet-unknown factor in fiber that produces a positive effect, says John Baron, an epidemiologist at Dartmouth Medical School.
Lupton says the data are stronger for type 2 diabetes, since a high-fiber diet has been linked to lower risk in several major studies. Other research shows that eating fiber may help prevent obesity and, of course, constipation.
In the end, many experts believe total fiber may really just be a proxy for healthy eating habits. "My feeling is that fiber itself has an effect, but other things-known or not-in healthy foods are also important," says Denis Lairon, the researcher who conducted the French study.
"High-fiber foods are nutritious foods," adds Lupton. "If you were to meet your recommended intake for fiber from foods and not exceed your calorie allotment, it would be extremely difficult to not eat a good diet."
Some fibers may prove better than others in the case of two specific health conditions. To combat sky-scrapingly high "bad" cholesterol levels, Mark G., a psychologist who lives just outside of Boston, makes a bowl of oatmeal every morning using 3?4 cup old-fashioned oats. This provides 3 grams soluble fiber, the type that binds LDL "bad" cholesterol and prevents it from wreaking havoc in his blood vessels. Along with regular exercise and some weight loss, Mark's morning "medicine bowl" (a suggestion from his physician) has lowered his cholesterol by 40 points. Good choices of soluble fiber: barley, oatmeal, beans, peas, citrus fruits, pears, apples, strawberries and eggplant.
Insoluble fiber, which absorbs water and increases in bulk, helps move food through the gastrointestinal tract, helping prevent constipation. Good choices of insoluble fiber: most whole grains, such as whole-wheat bread and wheat bran, cabbage, beets, bananas, carrots, tomatoes and Brussels sprouts.
Eating 25 grams of fiber per day (for women) or 38 grams (for men) seems daunting-until you make it a habit.
A day's sample menu (grams are per cup):
Raisin bran = 7 g
Raspberries = 8 g
Whole-wheat spaghetti = 6 g
Black-bean or lentil soup = 7 g
Chocolate Mousse a l'Orange
Enjoy this low-fat mousse spoonful by lovin' spoonful: it is just as luscious as its full-fat cousin.
Makes 6 servings
ACTIVE TIME: 40 minutes
TOTAL TIME: 4 hours 20 minutes
EASE OF PREPARATION: Challenging
3/4 cup low-fat milk
6 2-inch-long strips of orange zest
1 teaspoon unflavored gelatin
2 tablespoons Grand Marnier or other orange-flavored liqueur
1 large egg
1 cup packed light brown sugar, divided
2/3 cup unsweetened cocoa powder, preferably Dutch-process
2 ounces bittersweet (not unsweetened) chocolate, chopped
2 teaspoons vanilla extract
4 large egg whites
1/2 teaspoon cream of tartar
3 tablespoons water
1 2-ounce block bittersweet (not unsweetened) chocolate for chocolate shavings (optional) (see Tip)
NUTRITION INFORMATION: Per serving: 289 calories; 9 g fat (4 g sat, 1 g mono); 38 mg cholesterol; 53 g carbohydrate; 8 g protein; 5 g fiber; 68 mg sodium; 237 mg potassium. 3 1/2 Carbohydrate Servings.
Tip: To make chocolate shavings: Place a block of chocolate (2 ounces or larger) on wax paper and microwave on Defrost until slightly softened but not melted, 15 to 30 seconds. Use a swivel-bladed vegetable peeler to shave off curls. If the chocolate gets to hard to shave easily, warm it again.
MAKE AHEAD TIP: Cover and refrigerate for up to 2 days.
Sweet Potato & Black Bean Chili
A rich, dark and flavorful combination of our favorite Southwestern flavors. It also doesn't hurt that sweet potatoes and black beans both make the cut as superfoods. Serve with some warmed corn tortillas and Orange & Avocado Salad.
Makes 2 servings, 2 cups each
ACTIVE TIME: 20 minutes
TOTAL TIME: 30 minutes
EASE OF PREPARATION: Easy
2 teaspoons extra-virgin olive oil
1 small onion, finely diced
1 small sweet potato, peeled and diced
2 cloves garlic, minced
1 tablespoon chili powder
2 teaspoons ground cumin
1/4 teaspoon ground chipotle chile (see Note)
1/8 teaspoon salt, or to taste
1 1/3 cups water
1 15-ounce can black beans, rinsed
1 cup canned diced tomatoes
2 teaspoons lime juice
2 tablespoons chopped fresh cilantro
Heat oil in a large saucepan over medium-high heat. Add onion and potato and cook, stirring often, until the onion is slightly softened, about 4 minutes. Add garlic, chili powder, cumin, chipotle and salt and cook, stirring constantly, until fragrant, about 30 seconds. Add water, bring to a simmer, cover, reduce heat to maintain a gentle simmer and cook until the potato is tender, 10 to 12 minutes. Add beans, tomatoes and lime juice; increase heat to high and return to a simmer, stirring often. Reduce heat to maintain a simmer and cook until slightly reduced, about 4 minutes. Remove from the heat and stir in cilantro.
NUTRITION INFORMATION: Per serving: 374 calories; 6 g fat (1 g sat, 4 g mono); 0 mg cholesterol; 67 g carbohydrate; 14 g protein; 15 g fiber; 697 mg sodium; 603 mg potassium. Nutrition bonus: Vitamin A (410% daily value), Vitamin C (45% dv), Iron (30% dv), Potassium (17% dv). Exchanges: 4 starch, 1 1/2 vegetable, 1 fat. 3 1/2 Carbohydrate Servings
Note: Chipotle peppers are dried, smoked jalapeno peppers. Ground chipotle can be found in the specialty spice section of most supermarkets.
MAKE AHEAD TIP: Add all the ingredients except the cilantro; cover and refrigerate for 2 days. Reheat, stir in the cilantro and add more lime if desired.
Tuscan-Style Tuna Salad
This streamlined version of a northern Italian idea is perfect for a summer evening: no-fuss, no-cook and big taste. You can even make it ahead and store it, covered, in the refrigerator for several days. If you do, use it as a wrap filling for the next day's lunch.
Makes 4 servings, 1 cup each
ACTIVE TIME: 10 minutes
TOTAL TIME: 10 minutes
EASE OF PREPARATION: Easy
2 6-ounce cans chunk light tuna, drained
1 15-ounce can small white beans, such as cannellini or great northern, rinsed (see Ingredient note)
10 cherry tomatoes, quartered
4 scallions, trimmed and sliced
2 tablespoons extra-virgin olive oil
2 tablespoons lemon juice
1/4 teaspoon salt
Freshly ground pepper to taste
Combine tuna, beans, tomatoes, scallions, oil, lemon juice, salt and pepper in a medium bowl. Stir gently. Refrigerate until ready to serve.
NUTRITION INFORMATION: Per serving: 253 calories; 8 g fat (1 g sat, 5 g mono); 53 mg cholesterol; 20 g carbohydrate; 31 g protein; 6 g fiber; 453 mg sodium; 451 mg potassium. Nutrition bonus: Fiber (25% daily value), Vitamin C (20% dv). 1 Carbohydrate Serving. Exchanges: 1 starch, 1 vegetable, 3 1/2 very lean meat, 1 fat
Ingredient Note: When you use canned beans in a recipe, be sure to rinse them first in a colander under cold running water, as their canning liquid often contains a fair amount of sodium.
MAKE AHEAD TIP: Cover and refrigerate for up to 2 days.
From www.eatingwell.com with permission. © 2008 Eating Well Inc.
Fiber is one of the most effective ways to lose weight without feeling deprived. Foods high in fiber can help us shed a few pounds with minimal effort. Eating less food isn't necessary to weight loss, but changing the type of food can help us attain that goal.
Dietary fiber (sometimes called "roughage" or "bulk") is the part of a plant that provides and maintains the plant's structure. This fiber cannot be digested by the human body; as it moves through the intestines (colon) undigested, it helps to keep food moving smoothly, helps to correct certain disorders of the colon, keeps the intestines functioning normally, and makes it easier for the body to eliminate waste through the stool.
Good in so many ways, fiber is easy to add to your diet.