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How to Choose Carbohydrates

Carbohydrates and Disease
So far, we've been concentrating on how to choose good and better carbohydrates for weight control. But selecting good and better carbs affects many aspects of your health. Choose wisely, and you may avoid the onset of some life-threatening health conditions as well as take control of others you already have.

Carbohydrate's Role in Disease Prevention and Management

Complex carbohydrates are the all-stars of disease prevention and disease management. That's because of their high fiber content as well as the abundance of vitamins, minerals, and phytonutrients they contain. Here's a look at how eating a diet filled with complex carbohydrates can prevent or improve a variety of health conditions and diseases.

carbohydrates and disease

Carbohydrates can be just as important
to your cholesterol and
heart disease as fat.

Heart disease. The traditional approach to treating or preventing cardiovascular disease (CVD) has long been a low-fat, high-carbohydrate diet. The connection between fat, especially saturated fat, and heart disease was established years ago. Saturated fat, found in particularly high amounts in red meat and full-fat dairy products, raises LDL cholesterol levels (the "bad" cholesterol). Researchers concluded that if people reduced the overall amount of fat in their diet, the amount of saturated fat would also drop. Since fat has more than twice as many calories as carbohydrate and protein (9 calories per gram for fat compared to 4 calories per gram for carbohydrate or protein), reducing the amount of fat in the diet and increasing the amount of carbohydrate would mean eating fewer calories. Excess body weight is a contributing factor for heart disease, so maintaining a healthy weight works to reduce CVD risk.

Typically, carbohydrate foods are naturally low in fat. When minimally processed, they contain fiber that helps reduce cholesterol levels by removing LDL from the body. Health professionals included carbohydrates in their recommendations for heart-healthy eating. However, people were not always counseled to eat more of the "healthy" carbs and fewer of the "less healthy" carbs and filled up on large portions of fat-free and refined carbohydrates. They may have been taking in less fat but certainly not fewer calories!

To help reduce the risk of heart disease, the American Heart Association (AHA) currently  recommends a diet rich in fruits; vegetables; legumes (beans); whole, unrefined, complex carbohydrates; low-fat dairy products; fish; lean meats; and poultry. The AHA also recommends reducing the amount of saturated and hydrogenated (trans) fats in the diet. Nutrition counseling and education recommendations from the American Dietetic Association, the AHA, and other organizations focus on the distinction between heart-healthy fats and the importance of "healthy" carbohydrates.

Gastrointestinal disease. Complex carbohydrates, such as whole fruits and vegetables, beans, and whole grains, are particularly helpful for improving overall gastrointestinal health. These foods are high in fiber, which plays a pivotal role in reducing the incidence of constipation and diverticulosis, a condition in which tiny pouches form inside the colon. Fiber may also reduce the risk of colon, stomach, and gallbladder cancers. But that's not the only benefit of these nutrient-rich foods. Increased intake of intact grains and other fiber-rich, whole, complex carbohydrate foods helps decrease pressure inside the intestinal tract and may help prevent diverticulosis as well as diverticulitis, the painful inflammation of the pouches. Many of these complex carbohydrate foods also pack vitamins and minerals, such as iron, zinc, magnesium, and a host of B vitamins, as well as antioxidants such as vitamins E and C, selenium, and beta carotene. The phytic acid found in whole grains may help reduce cancer risk by decreasing free radicals. Free radicals, molecules formed as a byproduct of various biochemical processes in your body, can damage cells. Reducing the amount of free radicals can in turn reduce the risk of cancer.

Diabetes. It's still unclear whether diabetes can be prevented by eating complex carbohydrates that have a low-GI ranking. One prevailing theory is that long-term intake of lots of high-GI carbohydrates increases the risk of type 2 diabetes. This is thought to result from either insulin resistance (see below) or by exhausting the pancreas as it works to produce constant, high levels of insulin. There is good evidence, however, that a diet filled with complex carbohydrates can help treat and manage diabetes. We've known for quite some time that people with diabetes don't need to stay away from all carbohydrate. The body processes all forms of carbohydrate the same way, turning them into sugar (glucose). It's the speed with which the carbohydrate is processed and its corresponding effect on blood sugar that is important in diabetes management. Since simple, refined carbohydrates raise blood sugar more dramatically than do complex carbohydrates, people with diabetes should eat low-GI carbohydrates rather than refined, high-GI carbs. Eating low-GI foods throughout the day -- at meals and for snacks -- can go a long way toward controlling blood sugar levels.

Insulin resistance. Insulin resistance is a condition that may make it difficult for some people to process simple carbohydrates, especially large portions of them at one time. Overwhelming or flooding the body with large intakes of carbohydrate forces the body to work extra hard to clear the glucose from the blood. In the case of insulin resistance, the body's tissues are not receptive to the message that insulin is there to unlock the cell and let glucose in to do its job. The result is high levels of glucose circulating in the bloodstream for extended periods of time. This causes the pancreas to work harder to crank out more insulin to shuttle all of the extra glucose into cells. Overworked pancreatic cells may eventually wear out and decrease insulin production, which is an early sign of type 2 (or non-insulin-dependent) diabetes. One way to reduce your chances of developing insulin resistance is by eating plenty of low-GI complex carbohydrates and fewer high-GI, refined, simple carbohydrates.

Obesity. You may not think of obesity as a health condition, but being considerably overweight puts you at risk for a number of different health problems. And people who are overweight typically respond differently to carbohydrates than people who are not. A diet of high-GI, refined carbohydrates may have a much more adverse effect on an obese person's health. For example, in the ongoing Nurses' Health Study, established at Brigham and Women's Hospital in 1976 with funding from the National Institutes of Health, the odds of having a heart attack are increased for overweight women who eat lots of simple (easily digested) carbohydrates. Additionally, volunteers following high-carbohydrate, low-fat diets experienced unhealthy changes in levels of HDL (the good cholesterol), triglycerides (a type of fat), blood sugar, and insulin-the changes being most pronounced in overweight, inactive people. People who are lean and active may be better able to handle a high-carbohydrate intake for a number of reasons. First of all, being overweight makes it more difficult for insulin to do its job helping glucose get into the cells to provide energy. Secondly, people who are more active require more fuel for energy and are particularly efficient at burning carbohydrate, which is the body's preferred source. This allows active people to burn excess carbohydrate for energy instead of storing it as fat. Finally, when you have less fat tissue and more muscle, the body is more efficient at processing and digesting food, including carbohydrates. Whole grains, legumes, fruits, and most vegetables are naturally low in fat and contain healthy carbohydrates and significant amounts of fiber, all of which contribute to an overall healthy eating plan. Human studies have produced mixed results in the low-GI/weight-loss arena, but it certainly isn't harmful to employ the GI when making daily food choices. Some people may experience weight loss as a result.

Your body needs fuel to function. Carbohydrates provide that fuel. In the next section, we'll discuss eating the right carbohydrates for exercise.

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.