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How Nutrition Works


The Truth About Carbohydrates
©2006 Publications International, Ltd. If you choose the right type and quantity, carbohydrates are crucial part of a balanced diet.

In recent years, carbohydrates have gotten a bad reputation -- and it's somewhat undeserved.  "Carbs" are often viewed as a calorie-laden horror, a diet wrecker, an even bigger enemy than fat. But nothing could be further from reality.

Carbohydrates are your best friends. They are your body's preferred fuel. Both complex and simple carbohydrates are broken down in digestion to glucose molecules, which are absorbed into cells and burned as a power source. When we say "burned," we mean it quite literally. In fact, the amount of energy provided by food is measured by the amount of heat it produces when burned; these units of heat are calories. All carbohydrates provide four calories per gram.

They may all have four calories per gram, but that doesn't mean that all carbohydrates are the same. There are actually two kinds of carbohydrate: simple and complex.

Simple Carbohydrates

Sugars are "simple" carbohydrates. They are closest to the completely broken down form that your body uses as fuel. In fact, glucose itself is the simplest sugar. So the body converts sugar directly into usable energy. Pure sugar foods, such as hard candies and soft drinks, raise your blood sugar level and your energy level temporarily -- sometimes called a "sugar high." However, the levels quickly drop below what they were before, in a rebound effect. This has been dubbed the "sugar blues."

Sugar's reputation is truly battle scarred, but with very little reason. Sugar isn't quite the evil substance you may think it is. Its biggest fault is with the company it keeps; it is often found in foods with little or no nutritional value. Some of the charges leveled at sugar are baseless, some may be justified but haven't been proved, and a few are all too true. Here are some of the true and false charges:

  • Sugar causes hyperactivity. False. Its reputation for creating sugar monsters -- kids that eat sugar and go berserk -- just isn't true. No well-designed scientific study has ever been able to prove a link between sugar and hyperactive behavior. Keep in mind that kids often overdo sweets at particularly exciting times of the year, such as birthdays and Halloween, when they're naturally wound up just from the excitement.
  •  Sugar causes diabetes. False. Although there is a connection between sugar and diabetes, it is merely guilt by association. Diabetes is a hereditary disorder that appears when you lack insulin (type 1) or you become insensitive to it later in life (type 2). Can eating a lot of sugar cause this insensitivity? No, but being overweight can, and people who eat sugary sweets often gain weight -- hence, the confusion.
  • Sugar causes cavities. True, but it is hardly the worst offender. All carbohydrates can contribute to tooth decay. Complex carbohydrates, such as starches, can be just as much to blame for cavities as sugar, if not more so. The bacteria that cause decay are not picky about what they eat; starches that stick to your teeth provide plenty of food for bacteria. Surprisingly, one of the worst offenders is crackers.

Fighting Disease With FiberA great deal of the credit for the preventive powers of complex carbohydrates goes to fiber -- a certain type of complex carbohydrate found in whole grains, legumes, fruits, and vegetables.It seems strange that something your body rejects can be so important to your health, but that's just the case with fiber -- the indigestible portion of carbohydrate. Your body can't break it down, so it passes right through and on out as waste. Yet to do without it is to invite trouble.Without fiber, the other substances in your intestines would just sit there, fermenting and stagnating. Any toxins from food or created by bacteria would have that much more time to be in contact with your intestinal walls. It's this exposure that is thought to be at least one cause of colon cancer.

Keeping things moving is a smart move that helps prevent other diseases and conditions as well: constipation, diverticular disease, hemorrhoids, and varicose veins. And the sticky properties of fiber keep diabetes, heart disease, and obesity at bay.

There are two types of fiber: soluble and insoluble. Insoluble fiber is the type that probably comes to mind when you think of fiber. It's found in the wheat bran that's in most bran cereals. The fact that it doesn't dissolve in water is what makes it so beneficial. Instead, it soaks up water like a sponge. This softens stool and increases its bulk, which puts pressure on the walls of the intestines and speeds the stool's movement through your body. If you make a regular habit of eating foods high in insoluble fiber, you can all but eliminate the worry of constipation and hemorrhoids, and it may decrease your risk of developing colon and rectal cancers.

Soluble fiber may not be as well known, but it's just as valuable. As soluble fiber dissolves in water, it forms gummy gels. These gels bind with substances you'd just as soon get rid of -- like bile acids. Remember oat bran? Well, it was no silly craze. Oat bran is rich in soluble fiber, and by binding with bile acids, it helps lower blood levels of cholesterol. The higher your blood cholesterol level, the more it can help you. To make a difference, eat oatmeal, a low-fat oat-bran muffin, or other foods high in soluble fiber, such as kidney and other beans, every day.

By slowing the absorption of carbohydrates, soluble fiber also helps keep blood sugar on an even keel. Some people with diabetes are able to control blood sugar better by increasing the soluble fiber in their diet. For those battling the bulge, the extra bulk in the stomach and its delayed emptying help curb the appetite without adding calories.

How much is enough? Most Americans don't get even close to the recommended amount of fiber -- 20 to 35 grams per day. The average American gets about 10 to 15 grams per day. To boost your intake, make some simple adjustments in your daily diet:

  • Switch to whole-wheat bread and whole-wheat pasta.
  • Start your day with a bowl of bran cereal.
  • Eat whole fruits instead of just drinking juice.
  • Get five servings (2.5 cups) of vegetables every day.

Can you get too much? Yes, excessive fiber can interfere with mineral absorption, but you'd consistently have to take in more than 50 grams per day to be worried. Few people have that problem. A more common problem is that people increase their fiber intake too fast, resulting in gas, bloating, and intestinal discomfort. These gastrointestinal problems can be prevented by adding high-fiber foods gradually over six to eight weeks.You must also be sure to drink enough water and other fluids, especially when you eat foods high in insoluble fiber. They soak up the available water in your intestines; if there isn't enough, you could end up with an intestinal blockage -- rare, but serious.Fitting In FiberUpping your intake of fiber can be easier than you think, and you already know the benefits can be great (reduced risk of heart disease and cancer to name only two). Boosting your fiber intake can go hand-in-hand with cutting back the fat, as long as you do it right. Here are some tips for filling up with fiber.

  • Switch to the whole-grain version of the foods you normally eat: brown rice instead of white rice; potatoes with the skin instead of peeled; whole-wheat bread instead of white bread; whole-wheat or lupin pasta instead of semolina pasta; whole-wheat or buckwheat pancakes instead of regular; bran muffins instead of blueberry muffins; graham crackers instead of buttery crackers; and so on. Then try adding new grains: barley, millet, triticale, and quinoa for extra fiber and pizzazz.
  • Start your day with bran -- either a cereal or a muffin (if it's not too high in fat). You could be a third of the way to your daily fiber goal if you choose your cereal wisely.
  • Slice up dried apricots, prunes, or other fruits to add to your cereal; dried fruits are an excellent source of fiber.
  • Opt for the whole fruit instead of juice whenever you can. Juicing removes most of the fiber, especially if the juice is pulp-free.
  • Fruits with seeds are a powerhouse of fiber; raspberries and blackberries are the richest in fiber, but strawberries, blueberries, figs, and elderberries are chock full.
  • Top your sandwiches with spinach instead of lettuce; add tomato, avocado, or sweet peppers. Use your imagination, but get some fiber-filled veggies in there.
  • Find new ways to add vegetables: Add lightly steamed vegetables to spaghetti sauce, layer vegetables in your casseroles, or add vegetable purees to soups, sauces, and casseroles when cut-up veggies won't work.
  • Top your salads with lentils, chickpeas, green peas, and florets of broccoli.
  • Add wheat germ into any baked product you make: cookies, brownies, muffins, quick breads, and especially pancakes. You can replace one-half to one cup of flour with wheat germ (you may need to add a little extra liquid, though, and don't replace more than half of the flour).

On the other end of the diet spectrum is protein. Some diets, like the Atkins diet, would have you eat all protein and no carbohydrates. In the next section, we'll tell you everything you need to know about protein. This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.