Howstuffworks "Diabetes and Carbohydrates"

Potatoes and pinto beans. Carrots and cauliflower. Rye bread and rock candy. These foods have one thing in common: They're all sources of carbohydrates, which are the body's favorite source of energy. Although they are made up of only carbon, hydrogen, and oxygen, carbohydrates come in all shapes and sizes. They are found in fruits, vegetables, grains, beans, dairy foods, and just about everything you eat other than meat, fish, or fat.

And the different kinds of carbohydrates have different effects on your body and your blood sugar. This article defines the different types of carbohydrates, explains how to count carbohydrates, and talks about the importance of eating the right carbohydrates, as well as eating the right amount of fiber. We'll get started on the next page by helping you understand the various types of carbohydrates.

For more information on diabetes, diet, and related topics, try the following links:

For more information about how diet affects diabetes, see our Diabetic Diet page.
To learn how exercise relates to diet when you have diabetes, see our Diabetes and Exercise page.
For more information on diabetes in general, whether you want to learn about type 1 or type 2, visit the main Diabetes page.
To learn about how to take care of yourself when you have diabetes, visit our main Diabetes Treatment page.

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.

Types of Carbohydrates

Carbohydrates are in most of the foods that you eat. However, they vary in their molecular make-up and in how your body reacts to them. Broadly speaking, carbohydrates fall into three categories:

Sugars. The word "sugar" may make you think of the white granules you spoon into coffee or add to baked goods, but the sweet stuff comes in many varieties. Made up of relatively simple combinations of molecules, the sugars include sucrose (found in table sugar and some fruits and vegetables), fructose (found in fruit and honey), and lactose (found in milk), among others.

Starches. Although they consist of sugar units, the complex structure of starches makes them a distinct type of carbohydrate. (In fact, nutritionists used to call starches "complex carbohydrates," though the term has fallen out of favor with many of them.) The large size of starch molecules also sets them apart from sugars; they're too big for taste bud receptors on the tongue, which is why starches usually don't taste sweet. Starchy foods include potatoes, bread, pasta, and rice.

Fiber. Your grandma called it "roughage." Your gut calls it "indigestible." Like starch, fiber is made up of an intricate array of sugar molecules. But the sugar molecules in fiber aren't absorbed into the bloodstream as fiber passes through the gastrointestinal tract; that's because the body lacks enzymes to break it down. But even though fiber isn't a nutrient, per se, it does plenty of good, as you'll read later. Only plant foods naturally contain fiber; some rich sources include wheat bran and oat bran.

Your body reacts to the different types of carbohydrates in different ways.

Knowing the different types of carbohydrates will help diabetes patients determine how to manage their diets. The next section of this article explains how to count carbohydrates and suggests some tools you can use to get accurate measurements of the different types of carbohydrates.

For more information on diabetes, diet, and related topics, try the following links:

For more information about how diet affects diabetes, see our Diabetic Diet page.
To learn how exercise relates to diet when you have diabetes, see our Diabetes and Exercise page.
For more information on diabetes in general, whether you want to learn about type 1 or type 2, visit the main Diabetes page.
To learn about how to take care of yourself when you have diabetes, visit our main Diabetes Treatment page.

Counting Carbohydrates

While all foods cause glucose levels to rise, carbohydrates have the swiftest impact, producing an increase in blood sugar within two hours of a meal. However, several factors -- such as how much fiber or fat the meal includes -- can affect speed of digestion. About half of your calories (from 45 to 65 percent) should come from carbohydrates.

If you are taking insulin, carbohydrate counting is actually the most flexible eating plan. Carbohydrate counting allows you to more accurately estimate how much insulin you'll need to inject before eating in order to accommodate the ensuing rise in blood sugar. Your doctor or dietitian will recommend a number of insulin units per grams of carbohydrates in a meal. Chances are, at first you may need to experiment a little to find the right proportion. Carbohydrate counting can also help you eat roughly the same amount of carbs at each meal, which will help to maintain even, healthy blood sugar during the day.

If you're not taking insulin, the strategy of counting carbohydrates is kind of like living on a fixed income. You will get a set daily limit of how many carbohydrates you can eat, as measured in grams, but it's up to you to decide how you want to "spend" them at each meal. A slice of wheat bread has 13 grams of carbohydrates, and a medium-size apple packs about 20. Meanwhile, a small slice of chocolate cake will set you back 32 grams. Slurp down a McDonald's strawberry milk shake at lunch and you just blew 67 grams from your daily carb account.

Carbohydrate counting is not difficult; it just takes a little practice and access to two pieces of nutritional information: the number of carbohydrates in each food that makes up a meal and the amount of each food (or serving size) you will be eating. There are several good ways of getting this information:

Labels. With packaged foods, this information is printed on the Nutrition Facts panel.

The Nutrition Facts panel has all the information you need to
count carbs in packaged foods.

Your own research: For nonpackaged foods, books and Web sites for carbohydrate counters are available. Some restaurants provide the information.

Exchange lists. To make it simple to add variety to meals, the American Dietetic Association and the American Diabetes Association publish these easy-to-use lists. Foods are grouped by categories, such as starches, vegetables, fruits, meats, and so on, with predetermined portion sizes. All food exchanges within a category have roughly equivalent nutritional value and impact on blood sugar levels. For instance, if you wake up some morning and decide you want a bowl of cereal or oatmeal instead of your usual toast, an exchange list can tell you how much cereal or oatmeal you can eat and still keep your blood sugar level in the target range. Ask your diabetes educator or dietitian about exchange lists.

Counting your carbs is one step you can take to manage your diet with diabetes. The next section talks about choosing the right carbohydrates to improve your glucose control.

For more information on diabetes, diet, and related topics, try the following links:

For more information about how diet affects diabetes, see our Diabetic Diet page.
To learn how exercise relates to diet when you have diabetes, see our Diabetes and Exercise page.
For more information on diabetes in general, whether you want to learn about type 1 or type 2, visit the main Diabetes page.
To learn about how to take care of yourself when you have diabetes, visit our main Diabetes Treatment page.

Eating the Right Carbohydrates

Remember, there are no "bad" carbohydrates. But favoring some over others will improve your glucose control and give your overall health a boost. Here are some good rules to follow.

Go With the (Whole) Grain

If you think 7-grain bread, brown rice, and whole-wheat pasta are just for people who wear Birkenstocks and beads, it's time to get hip to the benefits of whole grains. Most Americans grew up eating white bread and white pasta. Wheat is the grain most commonly used to make these starchy foods. Picture a wheat field. Notice something that doesn't quite fit? Wheat isn't white. Millers produce white flour by grinding wheat to remove the sturdy outer layers of the grain, known as the bran and germ. Unfortunately, the process known as refining not only strips away the bran and germ, but it also removes lots of fiber, vitamins (especially vitamins B and E), and minerals, too. The same thing happens when rice is processed to make it pearly white.

The

U.S.

government requires commercial bakers to restore some of those nutrients; the process is known as enrichment. But some nutritionists believe that the body is better able to absorb and use naturally occurring vitamins and minerals. What's more, enrichment does not return to the finished product the countless micronutrients in grains, whose role in health scientists are only now beginning to understand.

Whole-grain breads, pasta, and rice are made with the entire grain, preserving all of those valuable nutrients. Whole grains have a bolder taste and chewier texture than most of their paler cousins. Add them to your diet, and over time, you may find that white bread and other refined grains taste bland. Beware of imitators: Some commercial bakeries sell "wheat" bread that is simply white bread that has been dyed brown. Pasta makers sometimes dye pasta brown, too, to make it appear healthier. Look for the words whole grain or whole wheat on package labels.

Don't Peel Out

Paring off the skin of apples or other fruits strips away fiber and nutrients, so leave it on. Corn and beans have edible skin, too. Foods with edible seeds, such as berries, are fiber filled, too.

An apple a day does even more for you
if you leave the peel on.

Get Colorful

Nutritionists believe that the same chemicals that give certain kinds of fruits and vegetables a brilliant hue may also promote health and fight disease. Tomatoes and watermelon, for instance, get their red color from an antioxidant called lycopene, which may prevent some cancers. You may want to see green on your plate, in particular. Some researchers believe that the antioxidants lutein and zeaxanthin, which are found in spinach, collards, kale, and broccoli, may strengthen the retina, the ring of nerve cells in the eyes that are vulnerable to blinding damage from high blood sugar.

Know Your Beans

They aren't as glamorous as prime rib or lobster, but lowly legumes are among the healthiest foods on the planet. Packed with fiber, protein, B vitamins, and other nutrients, beans and lentils belong on any healthy menu. There is an astonishing array of beans, from garbanzos to great northerns, each with a distinct taste. Beans go well in salads, stews, and soups, as well as curries, casseroles, and an endless list of ethnic dishes.

In choosing your carbohydrates, you'll also want to pay close attention to fiber content. Learn more about eating the right amount of fiber in the next section of this article.

For more information on diabetes, diet, and related topics, try the following links:

For more information about how diet affects diabetes, see our Diabetic Diet page.
To learn how exercise relates to diet when you have diabetes, see our Diabetes and Exercise page.
For more information on diabetes in general, whether you want to learn about type 1 or type 2, visit the main Diabetes page.
To learn about how to take care of yourself when you have diabetes, visit our main Diabetes Treatment page.

Eating the Right Amount of Fiber

Remember back in the 1980s, when oat bran bread became the toast of the town? Research suggested that eating oats and other high-fiber foods could fight heart disease and some cancers, making consumers weaned on white bread switch to dark loaves. Boring bran cereal became hip. Bakeries added oat muffins and bagels to their menus.

Food trends come and go, of course, so fiber's reputation as a health savior has faded slightly. However, fiber should never go out of fashion in your diet. There are two kinds of fiber in food:

Insoluble fiber. As the name suggests, this is fibrous stuff in plants that doesn't dissolve as it passes through the gastrointestinal system, so you can't digest it. Instead, insoluble fiber absorbs water and helps move waste through the colon. Whole-wheat bread is a good source of insoluble fiber, as are many vegetables.

Soluble fiber. This isn't digested, but it does get gummy in your gut. That allows it to grab fat molecules before they can be absorbed into the blood, whisking them out of the body through the intestines. Along with oat bran, dried peas and beans, barley, apples, oranges, carrots, and other fruits and vegetables are rich in soluble fiber.

Although fiber is a type of carbohydrate, your body can't digest it, so you can't burn it as energy. However, fiber has a long slate of benefits. Health authorities recommend eating 25 to 30 grams of fiber per day, yet Americans only consume about 14 or 15 grams daily, on average. Which is too bad, since:

Fiber helps control blood sugar. Fiber in a meal slows other carbohydrates from entering the bloodstream, which prevents glucose spikes. It's as though sugar and starch molecules keep bumping into all that roughage while trying to get out of your gut. A 2004 scientific review in the Journal of the American College of Nutrition found that eating high-fiber foods consistently lowers postmeal glucose levels in people with diabetes.

Beans and lentils are packed with
fiber, in addition to protein, B
vitamins, and other nutrients.

Fiber lowers cholesterol and other blood fats. The same review found solid evidence for the theory that daily doses of dietary fiber reduce cholesterol and triglycerides, another form of artery-clogging fat. That seems to be true of soluble fiber in particular; it sops up cholesterol and fat in the diet before it can enter the bloodstream.

Fiber fills you up. So does fat -- but fat has almost twice as many calories per gram as high-fiber foods. Eating plenty of low-calorie foods that provide satiety -- that belly-pleasing sense of fullness that persuades you to set down your fork and push away from the dinner table -- can help control weight.

Fiber is a freebie. Since you don't digest fiber, it has no calories. In fact, if you count carbs and consume a meal that includes more than five grams of fiber, you can subtract them from the overall gram count for the meal.

Fiber has lost a tiny bit of its miracle-food image in recent years. That's because studies suggest that roughage may not reduce the risk of colon cancer, as doctors once believed. Furthermore, if you develop gastroparesis or certain other gastrointestinal complications of diabetes, your doctor may recommend cutting back on fiber-rich foods, at least temporarily.

A final caveat: While fiber supplements can offer a convenient and effective way to add bulk to your diet, try to get your fill from foods. High-fiber pills, powders, and snacks contain natural substances such as psyllium seed husks (which come from a type of plantain). But fiber-dense foods are also excellent sources of vitamins, minerals, and other salubrious stuff. What's more, it's worth noting that fiber supplements are commonly used as laxatives, so it's important to use them as -- and only when -- prescribed.

For more information on diabetes, diet, and related topics, try the following links:

For more information about how diet affects diabetes, see our Diabetic Diet page.
To learn how exercise relates to diet when you have diabetes, see our Diabetes and Exercise page.
For more information on diabetes in general, whether you want to learn about type 1 or type 2, visit the main Diabetes page.
To learn about how to take care of yourself when you have diabetes, visit our main Diabetes Treatment page.

ABOUT THE AUTHOR:

Timothy Gower is a freelance writer and the author of several books. His work has appeared in many magazines and newspapers, including Prevention, Health, Reader's Digest, Better Homes and Gardens, Men's Health, Esquire, Fortune, The New York Times, and The Los Angeles Times.

ABOUT THE CONSULTANTS:

Dana Armstrong, R.D., C.D.E., received her degree in nutrition and dietetics from the University of California, Davis, and completed her dietetic internship at the University of Nebraska Medical Center in Omaha. In private practice for 21 years, she has developed educational programs that have benefited more than 5,000 patients with diabetes. She is the cofounder and program director of the Diabetes Care Center in Salinas, California.

Allen Bennett King, M.D., F.A.C.P., F.A.C.E., C.D.E., received his degrees and training at the University of California, Berkeley; Creighton University Medical School; the University of Colorado Medical Center; and Stanford University Medical Center. He is the author of more than 50 papers in medical science and speaks nationally on new advances in diabetes.