- Fiber curbs overeating. Fibers are filling without fattening. High fiber foods require more chewing, and the prolonged chewing, besides pre-digesting the food, satisfies the appetite so you eat less. Fiber stays in the stomach longer, absorbs water, swells, and helps the eater feel full. Because of this feeling of fullness, people on high fiber diets tend to eat more slowly and eat less, especially less fat. Best fibers for weight control –>are bran and the pectin from fruits.
Fiber Soaks Up Fat
Eat high-fiber foods with high-fat foods to decrease the absorption of fat. Increase your daily fiber and you’ll absorb fewer calories.
- Fiber steadies your blood-sugar level. Fiber, especially the soluble type, found in psyllium, bran, and legumes slows the absorption of sugar from the intestines. This steadies the blood sugar level and lessens the ups and downs of insulin secretion. So a breakfast and lunch containing moderate amounts of soluble fibers, such as bran, fruit, and oats, can be especially valuable to a child who shows behavior and learning difficulties from blood sugar swings. Keeping insulin levels low and stable also helps the body store less fat, another perk for people trying to control their weight.
- Fiber slows fat absorption. Fiber may also slow down the absorption of fat from what you eat. This is another weight-control perk offered by a high-fiber diet. The stools of persons eating a high-fiber diet have a higher fat content than stools from someone eating low-fiber meals.
- Fiber reduces cholesterol. A diet high in soluble fiber, such as that found in oat bran, whole oats, psyllium, legumes, barley, fruit, and prunes, lowers blood levels of the harmful type of cholesterol (LDL) without lowering the good cholesterol (HDL) levels. As it travels down the intestines, soluble fiber absorbs water and forms a gluey gel which picks up cholesterol and carries it out of the body. Yet, doctors caution, adding more soluble fibers to your diet is not a license to eat high cholesterol foods. High fiber diets are usually low in fat, too, and the cholesterol-lowering effects may be related to less fat in the diet as well as to fiber. Recent studies showed that eating an extra ten grams of fiber daily (the average American adult eats only eleven grams of fiber a day), decreased the risk of dying from heart disease by 17-29 percent.
- Fiber promotes regularity. Insoluble fibers, mainly the cellulose in skins of fruits and vegetables and the husks of grains help prevent constipation; their sponge effect absorbs a lot of water into the stools, making them soft and bulky. This type of stool stimulates the intestines to contract in an undulating way, called peristalsis, which sweeps stools along — the broom effect of fiber. In cultures that typically eat higher fiber diets, people tend to produce stools that are softer, larger, and more frequent, unlike the smaller, harder, and less frequent stools associated with the typical Western diet.
- Fiber reduces cancer risk. While soluble fiber helps protect against cardiovascular diseases, insoluble fiber protects against colon cancer. The incidence of colon cancer is significantly lower in cultures where people eat lots of high-fiber food. Increasing your consumption of insoluble fiber, such as that found in whole grains, especially wheat bran (i.e., All-Bran) is one of the most effective dietary changes you can make to decrease your risk of colon cancer. Here’s how fiber decreases the risk of colon cancer:
- Fiber increases peristalsis. One of the theories explaining the relationship between a high- fiber diet and a lower risk of colon cancer suggests that the longer potential toxins are in contact with the lining of the colon, the greater the chance of these lining cells becoming cancerous. So anything that decreases the contact time between the stools and intestinal wall will lower the risk of cancer. The bulkier, softer stools that result from a high-fiber diet stimulate peristalsis, the involuntary muscular contractions that keep food moving through the intestines. So fiber acts like a biological broom, sweeping potentially toxic waste products through the intestines more quickly. A high fiber diet can cut the transit time in half, thereby reducing the time that the lining of the bowel walls are exposed to potential cancer-causing substances.
- Fiber binds carcinogens. Besides moving carcinogens (toxins that can transform normal cells into cancerous ones) through the bowels faster, fiber binds these substances, lessening their contact time with the intestinal wall. The water and bulk of the stools also dilutes carcinogens, decreasing their potential to do harm. In addition, fiber absorbs bile acids and other potential irritants that may predispose the intestinal lining to cancer. Studies of persons at high risk for colorectal cancer showed that those eating a high fiber diet (primarily wheatbran) had a much lower chance of going on to develop colon cancer than those on a low fiber diet. While more and more studies confirm the link between high-fiber diets and lowered risk of colon cancer, the effect of fiber on other cancers is less clear. Preliminary studies have shown that high-fiber diets may decrease the risk of stomach and breast cancer. There are several possible explanations for this. Fiber binds estrogen in the intestines, thereby reducing the chance of breast cancer . Fiber also binds toxins, keeping them away from vulnerable tissues.A recent article in The New England Journal of Medicine received a lot of publicity by reporting on the results of a study in which the eating habits of 88,000 nurses were tracked over sixteen years. The study found that there was no difference in the incidence of colorectal cancer between those who ate a low-fiber diet and those who ate a high-fiber diet. In my opinion, the conclusions of this study are questionable. The study is purely a statistical analysis, and it contradicts the findings of other studies. In addition, it makes good physiological sense that a high-fiber diet could reduce the risk of many cancers, including colorectal cancer. As a physician, whenever I read the results of a study that doesn’t agree with common sense and sound physiological principles, I question its relevance. As is the case with many “conclusions” in medicine, tune in for the results of similar studies soon to come.
- Fiber promotes healthy intestinal bacteria. Fiber promotes overall colon health by discouraging the growth of harmful bacteria in the intestines and encouraging the growth of beneficial bacteria. This is thought to contribute to the lowered risk of colorectal cancer associated with a high-fiber diet. Fiber also contributes to a friendlier intestinal environment – the friendly bacteria in the colon ferment fiber into short-chain fatty acids (SCFA’s), healthy nutrients that can be used by the body. The friendly bacteria in the intestines seem to prefer rice bran and barley bran, balanced sources of soluble and insoluble fiber, to make these nutritious fatty acids. These foods are also rich in vitamin E compounds called “tocotrienols,” which are natural cholesterol-lowering substances.
- Fiber is a family food. In addition to being friendly to aging bowels, fiber is also valuable for school-age children, mainly because it delays the absorption of sugars from the food into the bloodstream, making the blood sugars more stable – and, consequently, making the children more likely to behave and learn better. Send your child off to school with a breakfast containing at least 5 grams of fiber, the amount contained in a medium-fiber cereal and one serving of fruit.