Heart Risk Linked to Simple Carbs

A diet rich in carbohydrates that are quickly transformed into sugar in the blood raises the risk of heart disease for women, a new study finds.

The same effect, however, is not seen in men.

The Archives of Internal Medicine study, led by researchers at Italy's National Cancer Institute, looked at total carbohydrate intake and the glycemic index of those carbohydrates.

Glycemic index is a measure of how quickly and to what extent blood sugar rises after intake of specific carbohydrates. Foods with similar calorie content can show widely different scores on the glycemic index.

Carbohydrates with a high glycemic index include corn flakes, white bread, and white rice. Those with lower scores include whole wheat products and sweet potatoes.

Expert Victoria J. Drake, Ph.D., at Oregon State University, says, "A high glycemic index is known to increase the concentration of triglycerides and lower the concentration of HDL cholesterol, the good kind. Those adverse effects make it a stronger risk factor for heart disease."

Watch for High Sugar Count in Foods

Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in New York City, says the study shows the need for women to be more aware of the nature of the carbohydrates in their diet.

"An emphasis needs to be placed on a diet that is not simply low in carbohydrates but rather low in simple sugars, as measured by the glycemic index," says Dr. Steinbaum.

There is a simple way to determine the glycemic index of a food.

"Look at the label," explains Dr. Steinbaum. "It says 'carbohydrates.' Under that, it says 'sugars.' When you have a high number for sugars, that's a way to know what the glycemic index is."

That index can differ widely in foods that do not appear to be different, she says. One breakfast cereal may have a sugar content of 16 grams, but another may have just 3 grams to 6 grams.

"If you see a high level of sugar, that's the one to stay away from," says Dr. Steinbaum.

Risk for Women Considered Significant

For the study, the researchers looked at dietary intake questionnaires filled out by 15,171 men and 32,578 women. They followed them for nearly eight years.

The researchers found that women who consumed the most carbohydrates overall had about twice the incidence of heart disease as those who consumed the least.

Closer analysis showed that the risk was linked with higher intake of high-glycemic foods.

A high consumption of carbohydrates from high-glycemic index foods, rather than the overall quantity of carbohydrates consumed, appears to influence the development of coronary heart disease.

Previous studies have seen the same effect in other groups of women, says Dr. Drake. Observations include the Nurses Health Study, done in the US, and studies of women in the Netherlands.

Regarding findings on men in the study, no effect from total carbohydrate consumption or intake of foods with a high-glycemic index was seen.

"There is definitely a gender difference," notes Dr. Drake.

The difference might be due to the action of sex hormones, the researchers speculate.

Male hormones, androgens, appear to slow the transformation of carbohydrates into blood sugar, whereas the female hormone estrogen speeds the process.

Always consult your physician for more information.