Good Carbs vs Bad Carbs: New Science

In an analysis of the dietary habits of nearly 600 healthy people from central Massachusetts, researchers found that those who were overweight did not consume more carbs overall than thinner people.  The overweight subjects, however, did tend to eat more refined (bad) carbohydrates, dense with calories, such as white bread and white rice.  The leaner men and women ate more unrefined (good) carbs, like whole-wheat bread, brown rice, beans, fruits, and vegetables.*

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Researchers found that those who were overweight did not consume more carbs overall than thinner people.

In an analysis of the dietary habits of nearly 600 healthy people from central Massachusetts, researchers found that those who were overweight did not consume more carbs overall than thinner people.  The overweight subjects, however, did tend to eat more refined carbohydrates, dense with calories, such as white bread and white rice.  The leaner men and women ate more unrefined carbs, like whole-wheat bread, brown rice, beans, fruits, and vegetables.*

Good Carbs vs Bad Carbs

Lead researcher Dr. Yunsheng Ma of the University of Massachusetts Medical School suggested that knowing a carbohydrate’s glycemic index might be useful.  Refined carbs tend to have a high glycemic index, meaning they cause a rapid increase in blood sugar.  In contrast, fiber-rich unrefined carbs like whole grains, fruits, and vegetables tend to have a low glycemic index.

Many nutrition experts, however, do not endorse the glycemic index as a weight-loss tool because it is fraught with problems.  A food’s glycemic index, for instance, can fluctuate depending on how much is eaten and what other foods are eaten at the same time.  And a high glycemic index doesn’t necessarily mean high sugar levels.  Carrots, for example, have a high glycemic index, but you’d have to eat over a pound to spike the blood sugar as high as the glycemic index warns.

Consequently, no leading health or government institution in the U.S., including the USDA’s Dietary Guidelines, supports or endorses public health campaigns based on the glycemic index.  The 13-member committee of leading scientists from academia who devised the guidelines after examining thousands of studies concluded that the glycemic index is of “little utility for providing dietary guidance for Americans.”

To control weight and give your body the nutrition it needs, your best bet is a diet that emphasizes – not indexes – but unrefined carbohydrates like fruits, vegetables, and whole grains.

* American Journal of Epidemiology, 2005; 161(4): 359.

DID YOU KNOW?

It takes 2 quarts of air-popped popcorn, an unrefined carbohydrate, to equal the calories in just 20 potato chips.

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