| Diets low in saturated fat and cholesterol | | | | As it passes through the gastrointestinal |
| and high in fiber are associated with a | | | | tract, soluble fiber binds to dietary |
| reduced risk of certain cancers, diabetes, | | | | cholesterol, helping the body to eliminate |
| digestive disorders, and heart disease. | | | | it. This reduces blood cholesterol levels, |
| | | | which, in turn, reduces cholesterol deposits |
| Diets low in fat and rich in fiber-containing | | | | on arterial walls that eventually choke off |
| grain products, fruits, and vegetables may | | | | the vessel. There also is some evidence that |
| reduce the risk of some types of cancer. | | | | soluble fiber can slow the liver's |
| | | | manufacture of cholesterol, as well as alter |
| Diets low in saturated fat and cholesterol | | | | low-density lipoprotein (LDL) particles to |
| and rich in fruits, vegetables, and grain | | | | make them larger and less dense. Researchers |
| products that contain fiber, particularly | | | | believe that small, dense LDL particles pose |
| soluble fiber, may reduce the risk of | | | | a bigger health threat. |
| coronary heart disease. | | | | |
| | | | Recent findings from two long-term |
| Diets low in fat and rich in fruits and | | | | large-scale studies of men suggest that high |
| vegetables, which are low-fat foods and may | | | | fiber intake can significantly lower the risk |
| contain fiber or vitamin A (as beta-carotene) | | | | of heart attack. Men who ate the most |
| and vitamin C, may reduce the risk of some | | | | fiber-rich foods (35 grams a day, on average) |
| cancers. | | | | suffered one-third fewer heart attacks than |
| | | | those who had the lowest fiber intake (15 |
| Found only in plant foods, such as whole | | | | grams a day), according to a Finnish study of |
| grains, fruits, vegetables, beans, nuts, and | | | | 21,903 male smokers aged 50 to 69, published |
| seeds, fiber is composed of complex | | | | in the December 1996 issue of Circulation. |
| carbohydrates. Some fibers are soluble in | | | | Earlier in the year, findings from an ongoing |
| water and others are insoluble. Most plant | | | | U.S. study of 43,757 male health |
| foods contain some of each kind. | | | | professionals (some of whom were sedentary, |
| | | | overweight or smokers) suggest that those who |
| Some foods containing high levels of soluble | | | | ate more than 25 grams of fiber per day had a |
| fiber are dried beans, oats, barley, and some | | | | 36 percent lower risk of developing heart |
| fruits, notably apples and citrus, and | | | | disease than those who consumed less than 15 |
| vegetables, such as potatoes. Foods high in | | | | grams daily. In the Finnish study, each 10 |
| insoluble fiber are wheat bran, whole grains, | | | | grams of fiber added to the diet decreased |
| cereals, seeds, and the skins of many fruits | | | | the risk of dying from heart disease by 17 |
| and vegetables. | | | | percent; in the U.S. study, risk was |
| | | | decreased by 29 percent. |
| Fiber's Health Benefits | | | | |
| | | | These results indicate that high-fiber diets |
| What can fiber do for you? Numerous | | | | may help blunt the effects of smoking and |
| epidemiologic (population-based) studies have | | | | other risk factors for heart disease. |
| found that diets low in saturated fat and | | | | |
| cholesterol and high in fiber are associated | | | | Obesity: Because insoluble fiber is |
| with a reduced risk of certain cancers, | | | | indigestible and passes through the body |
| diabetes, digestive disorders, and heart | | | | virtually intact, it provides few calories. |
| disease. However, since high-fiber foods may | | | | And since the digestive tract can handle only |
| also contain antioxidant vitamins, | | | | so much bulk at a time, fiber-rich foods are |
| phytochemicals, and other substances that may | | | | more filling than other foods--so people tend |
| offer protection against these diseases, | | | | to eat less. Insoluble fiber also may hamper |
| researchers can't say for certain that fiber | | | | the absorption of calorie-dense dietary fat. |
| alone is responsible for the reduced health | | | | So, reaching for an apple instead of a bag of |
| risks they observe, notes Joyce Saltsman, a | | | | chips is a smart choice for someone trying to |
| nutritionist with FDA's Office of Food | | | | lose weight. |
| Labeling. "Moreover, no one knows whether one | | | | |
| specific type of fiber is more beneficial | | | | But be leery of using fiber supplements for |
| than another since fiber-rich foods tend to | | | | weight loss. In August 1991, FDA banned |
| contain various types," she adds. | | | | methylcellulose, along with 110 other |
| | | | ingredients, in over-the-counter diet aids |
| Recent findings on the health effects of | | | | because there was no evidence these |
| fiber show it may play a role in: | | | | ingredients were safe and effective. The |
| | | | agency also recalled one product that |
| Cancer: Epidemiologic studies have | | | | contained guar gum after receiving reports of |
| consistently noted an association between low | | | | gastric or esophageal obstructions. The |
| total fat and high fiber intakes and reduced | | | | manufacturer had claimed the product promoted |
| incidence of colon cancer. A 1992 study by | | | | a feeling of fullness when it expanded in the |
| researchers at Harvard Medical School found | | | | stomach. |
| that men who consumed 12 grams of fiber a day | | | | |
| were twice as likely to develop precancerous | | | | Recent research suggests that as much as 35 |
| colon changes as men whose daily fiber intake | | | | grams of fiber a day is needed to help reduce |
| was about 30 grams. The exact mechanism for | | | | the risk of chronic disease, including heart |
| reducing the risk is not known, but | | | | disease. A fiber supplement can help make up |
| scientists theorize that insoluble fiber adds | | | | the shortfall, but should not be a substitute |
| bulk to stool, which in turn dilutes | | | | for fiber-rich foods. "Foods that are high in |
| carcinogens and speeds their transit through | | | | fiber also contain nutrients that may help |
| the lower intestines and out of the body. | | | | reduce the risk of chronic disease," Saltsman |
| | | | notes. In addition, eating a variety of such |
| The evidence that a high-fiber diet can | | | | foods provides several types of fiber, |
| protect against breast cancer is equivocal. | | | | whereas some fiber supplements contain only a |
| Researchers analyzing data from the Nurses' | | | | single type of fiber, such as methylcellulose |
| Health Study, which tracked 89,494 women for | | | | or psyllium. |
| eight years, concluded in 1992 that fiber | | | | |
| intake has no influence on breast cancer risk | | | | To fit more fiber into your day: |
| in middle-aged women. Previously, a review | | | | |
| and analysis of 12 studies found a link | | | | Read food labels. The labels of almost all |
| between high fiber intake and reduced risk. | | | | foods will tell you the amount of dietary |
| | | | fiber in each serving, as well as the Percent |
| In the early stages, some breast tumors are | | | | Daily Value (DV) based on a 2,000-calorie |
| stimulated by excess amounts of estrogen | | | | diet. For instance, if a half cup serving of |
| circulating in the bloodstream. Some | | | | a food provides 10 grams of dietary fiber, |
| scientists believe that fiber may hamper the | | | | one serving provides 40 percent of the |
| growth of such tumors by binding with | | | | recommended DV. The food label can state that |
| estrogen in the intestine. This prevents the | | | | a product is "a good source" of fiber if it |
| excess estrogen from being reabsorbed into | | | | contributes 10 percent of the DV--2.5 grams |
| the bloodstream. | | | | of fiber per serving. The package can claim |
| | | | "high in," "rich in" or "excellent source of" |
| Digestive disorders: Because insoluble fiber | | | | fiber if the product provides 20 percent of |
| aids digestion and adds bulk to stool, it | | | | the DV--5 grams per serving. |
| hastens passage of fecal material through the | | | | |
| gut, thus helping to prevent or alleviate | | | | Use the U.S. Department of Agriculture's food |
| constipation. Fiber also may help reduce the | | | | pyramid as a guide. If you eat 2 to 4 |
| risk of diverticulosis, a condition in which | | | | servings of fruit, 3 to 5 servings of |
| small pouches form in the colon wall (usually | | | | vegetables, and 6 to 11 servings of cereal |
| from the pressure of straining during bowel | | | | and grain foods, as recommended by the |
| movements). People who already have | | | | pyramid, you should have no trouble getting |
| diverticulosis often find that increased | | | | 25 to 30 grams of fiber a day. |
| fiber consumption can alleviate symptoms, | | | | |
| which include constipation and/or diarrhea, | | | | Start the day with a whole-grain cereal that |
| abdominal pain, flatulence, and mucus or | | | | contains at least 5 grams of fiber per |
| blood in the stool. | | | | serving. Top with wheat germ, raisins, |
| | | | bananas, or berries, all of which are good |
| Diabetes: As with cholesterol, soluble fiber | | | | sources of fiber. |
| traps carbohydrates to slow their digestion | | | | |
| and absorption. In theory, this may help | | | | When appropriate, eat vegetables raw. Cooking |
| prevent wide swings in blood sugar level | | | | vegetables may reduce fiber content by |
| throughout the day. Additionally, a new study | | | | breaking down some fiber into its |
| from the Harvard School of Public Health, | | | | carbohydrate components. When you do cook |
| published in the Feb. 12 issue of the Journal | | | | vegetables, microwave or steam only until |
| of the American Medical Association, suggests | | | | they are al dente--tender, but still firm to |
| that a high-sugar, low-fiber diet more than | | | | the bite. |
| doubles women's risk of Type II | | | | |
| (non-insulin-dependent) diabetes. In the | | | | Avoid peeling fruits and vegetables; eating |
| study, cereal fiber was associated with a 28 | | | | the skin and membranes ensures that you get |
| percent decreased risk, with fiber from | | | | every bit of fiber. But rinse with warm water |
| fruits and vegetables having no effect. In | | | | to remove surface dirt and bacteria before |
| comparison, cola beverages, white bread, | | | | eating. Also, keep in mind that whole fruits |
| white rice, and french fries increased the | | | | and vegetables contain more fiber than juice, |
| risk. | | | | which lacks the skin and membranes. |
| | | | |
| High-fiber diets may help blunt the effects | | | | Eat liberal amounts of foods that contain |
| of smoking and other risk factors for heart | | | | unprocessed grains in your diet: whole-wheat |
| disease. | | | | products such as bulgur, couscous or kasha |
| | | | and whole-grain breads, cereals and pasta. |
| Heart Disease: Clinical studies show that a | | | | |
| heart-healthy diet (low in saturated fat and | | | | Add beans to soups, stews and salads; a |
| cholesterol, and high in fruits, vegetables | | | | couple of times a week, substitute |
| and grain products that contain soluble | | | | legume-based dishes (such as lentil soup, |
| fiber) can lower blood cholesterol. In these | | | | bean burritos, or rice and beans) for those |
| studies, cholesterol levels dropped between | | | | made with meat. |
| 0.5 percent and 2 percent for every gram of | | | | |
| soluble fiber eaten per day. | | | | Keep fresh and dried fruit on hand for |
| | | | snacks. |