Fiber, Fiber & More Fiber...

(Long article but well worth the read.)

FIBER


Grandma always told you that "roughage" was good for you, and now research is proving that fiber in foods is important to health. Fiber is the part of fruits, vegetables, and grains that is neither digested nor absorbed. Why should fiber matter to good nutrition, since it doesn't provide any calories or nutrients? Fiber helps keep your intestines working comfortably and helps prevent many diseases. Here is why fiber is so fantastic:

Fiber comes in two forms, soluble and insoluble. Each acts differently in the intestines and benefits the body in different ways. Soluble fiber acts like a sponge; insoluble fiber acts like a broom.

Soluble fiber. Found in dried beans and peas, oat bran, rice bran, barley, and fruit pectin (the substance used to thicken jams and jellies). Soluble fiber absorbs water in the intestines, mixes the food into a gel, and thereby slows the rate of glucose digestion and consequent absorption in the bloodstream.

Insoluble fiber. This is the stringy stuff that holds plants together. It's called "insoluble" because it doesn't dissolve in water. It can be found mainly in plant leaves, peels, skins, and the coverings of whole grains (e.g., wheat bran). Like a disposable diaper, insoluble fiber can absorb many times its own weight in water. This water adds bulk and softness to the stools and keeps them moving along more comfortably. Think of eating fiber like brushing your teeth - it cleans out your intestines daily.
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7 HEALTH BENEFITS OF FIBER

1. 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.

NUTRITIP:
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.

2. 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.

3. 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.

4. 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.

5. 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.

6. 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.

7. 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.

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HOW MUCH FIBER DO YOU NEED?

To get the full health benefits of dietary fiber, adults should eat 25 to 35 grams of fiber each day. Most Americans eat only around 11 grams. To calculate how much daily fiber your child needs follow this formula: age of child in years plus five. For example, a five-year-old would needs ten grams of fiber a day.

How much fiber is too much? Your intestines will tell you. Gradually build up the amount and variety of your daily fiber intake. Signs of insufficient fiber in a diet are:

* Constipation
* Infrequent stools
* Hard stools
* Abdominal pains
* A general feeling of "sluggish bowels"

Signs of too much fiber are:

* Excessive gassiness
* Bloating
* Abdominal pain
* Stools uncomfortably frequent and large overall volume

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FIBER TIPS FOR KIDS

* The skins of fruits are rich sources of fiber, so don't peel apples and pears. Cut these fruits up into easy-to-eat wedges, but leave the skins on. Serve your child nectar (which contains pulp) rather than fiberless plain juice. Better yet, serve the whole fruit rather than its juice.
* A child's age plus 5 grams is about the minimum amount for a child over two. So, a six- year-old should eat at least 11 grams of fiber; a fifteen-year-old should eat at least 20 grams.
* See related topics: Brainy breakfasts and School-ade.

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BEST FIBER FOODS

FOOD SERVING SIZE TOTAL FIBER (grams)*
AllBran cereal 1/2 cup 10-13
Psyllium husks 2 tbsp. (1 ounce) 16
Wheat bran 1/4 cup 7
High fiber cereals 1 ounce (1/2 cup) 10-14
Flax meal 1/4 cup 8
Apple (with skin) 1 medium 3.5
Oat bran 1/4 cup 4
Prunes 3 medium 3
Kidney beans 1/2 cup 7.3
Lima beans 1/2 cup 4.5
Navy beans 1/2 cup 6
Lentils (such as in soup) 1/2 cup 3.7
Peas 1/2 cup 3.6
Spaghetti (whole wheat) 1 cup 3.9
Apricots (dried) 5 halves 1.4
Banana 1 medium 2.4
Blueberries 1/2 cup 2.0
Grapefruit (with membrane) half 1.6
Pear 1 medium 3.2
Bread (whole wheat) 1 slice 1.4
Figs (dried) 3 medium 5.3
Chickpeas (garbanzo beans) 1/2 cup 7
Potatoes (with skin) 1 medium 2.5
Broccoli 1/2 cup 2.3
Sweet potato 1/2 cup 3
Orange (with membrane) 1 2.6
Spinach 1/2 cup 2.1
Pita bread (whole wheat) 1 piece 5
Corn 1 ear 5
Barley 1/2 cup 8

Best sources of soluble fiber are:
# oat bran
# kidney beans
# lentils
# sweet potatoes
# oranges
# broccoli
# pears
# apples
# barley
# peas

Best sources of insoluble fiber are:
# wheat bran
# legumes
# skin of fruit
# seeds and nuts: sunflower seeds, soybean nuts, almonds
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TEN EASY WAYS TO BOOST YOUR DAILY FIBER

1. Consume whole fruits and vegetables instead of juice. The peels on apples and the white pith on oranges are rich sources of fiber, as are potato skins.

2. Cut back on refined foods. "Enriched flour" means the product was originally impoverished. In many refined foods, the fiber-containing parts have been removed.

3. Try a daily yogurt smoothie (See School-ade) made in the blender with a couple handfuls of fresh fruits, such as strawberries, bananas, papaya, blueberries, and pears. Blend in a heaping tablespoon of psyllium husks. Drink it quickly before it gels.

4. Snack on dried fruits, such as apricots, figs, prunes, and raisins.

5. Use whole grains instead of white. White bread and white rice have had the fiber processed out of them. (This is why white bread and white rice have a reputation for being constipating.) Instead use whole grains: bread made with whole wheat flour, whole grain cereals that contain wheat bran or oat bran, whole grain cornmeal, wheat germ, and barley. Instead of white rice, use brown or wild rice.

6. Be a bean freak. Nearly all varieties of beans are a rich source of fiber, especially kidney beans, which can be served in many forms, such as in salads, soups, bean burritos, or chili.

7. Dip it. A chickpea dip (i.e. hummus) is nutritious and fiber-rich.

8. Choose a high-fiber cereal. If you find that high-fiber cereals are not the most palatable, try mixing a couple of tablespoons of All-Bran or psyllium husks with your favorite cereal to boost the fiber content. Add lots of milk, rice beverage, or juice and enjoy.

9. Choose your lettuce wisely. Iceberg lettuce is useless as a source of fiber and any other nutrients. Spinach and romaine lettuce are healthier choices.

10. Fresh fruits have more fiber than canned fruits because much of the fiber is in the peel, which is usually removed in processing.

Simply emphasizing grains, fresh fruits and vegetables in your diet will automatically get you enough fiber. A diet that revolves around meat, eggs, and dairy products will not contain enough fiber.
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6 WAYS TO HELP FIBER WORK BETTER IN YOUR BODY

Getting enough fiber is really quite simple. If you follow the recommendations of the Food Guide Wheel and include the amounts of healthy grains, fruits, legumes, and vegetables it suggests, you will automatically get enough fiber in your diet. Here are some tips on eating your fiber:

1. Increase the amount of fiber in your diet gradually. Your intestines will be more comfortable with this approach than with a sudden onslaught of high-fiber foods. Too much fiber too soon is likely to catch your intestines off guard, leading to bloating and gas. Each week increase the amount of fiber in your diet by about 5 grams a day for adults and 1 to 2 grams a day for children until you reach your individual intestines-friendly daily amount. This is usually somewhere between 25 and 35 grams a day for adults, and half that for children. Keep experimenting with the amount and type of fiber that gives you a comfortable "gut feeling."

SILLY PSYLLIUM

This super fiber is made from psyllium seeds ground into bran-like flakes. It has more water-absorbing capability (called "stool bulking capacity") than any other fiber. Yet, stronger is not necessarily better. Because of its high water- absorbing capacity, if not used wisely, it can actually gum up the stools, resulting in constipation, the very problem it was meant to cure. This is known as the psyllium syndrome. If using psyllium, take two precautions: Begin with only one teaspoon then gradually increase the amount until your stools are soft and you have no bloating or intestinal discomfort. Next, drink at least eight 8-ounce glasses of water a day when using psyllium.

2. It's important to eat fiber from a variety of sources. By eating many types of high fiber foods, you are more likely to balance out the right amount of soluble and insoluble fibers. The more soluble the fiber, the more it ferments, and therefore the more gas it produces.

NUTRIMINDER:
The 3 B's of Fiber

Remember the three B's of fiber: bran, beans, and berries. One serving of bran plus one serving of beans each day will give you over half your total daily fiber needs. And remember: bran and berries blend well into yogurt smoothies.

3. Spread out your dietary fiber throughout the day. Overdosing on fiber at any one meal is liable to produce bloating and gas.

NUTRIMINDER:
The 4 A's of Fiber

Remember the four A's of fiber: apples, artichokes, apricots, and avocados.

4. Drink a lot of water with your fiber. For fiber to do an adequate sweeping and sponging job, there has to be an adequate amount of water for it to absorb. Otherwise, fiber may actually contribute to constipation rather than prevent it, or it may soak up water and other nutrients needed elsewhere by the body.

5. Get your fiber from food, not from pills. The fiber in the pill may not work the same way biologically as fiber in food. For fiber to do its job, it needs to be eaten in the company of other foods and with a lot of fluids.

6. Avoid fiber-induced nutritional deficiencies. Overdosing on fiber can interfere with the absorption of valuable nutrients. Fiber can push food through the intestines so fast that some nutrients, such as calcium, zinc, vitamins, and iron don't have a chance to be fully absorbed. You could avoid eating high-fiber foods at the same time you eat foods containing these nutrients, but this is impractical. If you're on a diet that includes more than 35 grams of fiber a day, you should consider taking vitamin and mineral supplements.

+ Journal of the American Dietetic Association 86 (1986): 732

* The RDA for fiber is 25 grams for adults; for children it is child's age in years +5