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Good Carbs, Bad Carbs: What You Need to Know

A loaf of whole grain bread.
(Image credit: <a href=''>Whole grain bread photo</a> via Shutterstock)

"The Healthy Geezer" answers questions about health and aging in his weekly column.

Question:  What exactly is the difference between good carbs and bad carbs?

Answer: Here's the short answer: Good carbs — or carbohydrates — are good for you. Bad carbs aren't.

Carbohydrates that come from white bread, white rice, pastry, sugary sodas and other highly processed foods can make you fat. If you eat a lot of these so-called bad carbs, they will increase your risk for disease.

On the other hand, the good carbs, including whole grains, beans, fruits and vegetables, keep you healthy by providing you with vitamins, minerals, fiber and many other nutrients. That's why a healthy diet should include good carbs.

Carbohydrates are the most important source of energy for your body. Your digestive system converts carbohydrates into blood sugar (glucose). Your body uses the glucose and stores any extra sugar for when you need it.

Carbohydrates were once grouped into two main categories — simple and complex. Simple carbohydrates included sugars such as fruit sugar (fructose), corn or grape sugar (dextrose or glucose) and table sugar (sucrose). Complex carbohydrates included everything made of three or more linked sugars. Complex carbohydrates were thought to be the healthiest to eat. Now there are questions about that assumption.

A new system, called the glycemic index, classifies carbohydrates according to how quickly and how high they boost blood sugar. Foods with a high glycemic index, like white bread, cause rapid spikes in blood sugar. Foods with a low glycemic index, like whole oats, are digested more slowly, causing a lower and gentler change in blood sugar.

Diets rich in foods that have a high glycemic index have been linked to an increased risk for diabetes, heart disease, obesity, age-related macular degeneration, infertility and colorectal cancer. Foods with a low glycemic index help control diabetes and improve weight loss.

However, other studies have found that the glycemic index has little effect on health or weight. As a result, more research on the glycemic index is needed.

You can't base a diet on the glycemic index alone. Instead, use it as a general guide. In the meantime, eat foods that have a low glycemic index: whole grains, beans, fruit and vegetables.

The University of Sydney in Australia maintains an updated searchable database at that now has almost 1,600 entries.

Here are five quick tips about carb consumption from the Harvard School of Public Health:

1. Start the day with whole grains. Try a hot cereal, like old-fashioned oats, or a cold cereal that has a whole grain topping the ingredients list.

2. Use whole grain breads for lunch or snacks.

3. Bag the potatoes. Instead, have brown rice, bulgur, wheat berries, whole wheat pasta or another whole grain with your dinner.

4. Choose whole fruit instead of juice. An orange has twice as much fiber and half as much sugar as a 12-ounce glass of orange juice.

5. Bring on the beans. Beans are an excellent source of slowly digested carbohydrates as well as a great source of protein.

If you would like to read more columns, you can order a copy of "How to be a Healthy Geezer" at

All Rights Reserved © 2013 by Fred Cicetti.

Fred Cicetti is a contributing writer for Live Science who specializes in health. He has been writing professionally since 1963. Before he began freelancing, he was a reporter, rewriteman and columnist for three daily newspapers in New Jersey: The Newark News, Newark Star-Ledger and Morristown Record. He has written two published novels:" Saltwater Taffy—A Summer at the Jersey Shore," and "Local Angles—Big News in Small Towns."