Earlier this week, CNN and Health.com reported that white bread, rice, and other carbs – foods with high glycemic loads – boost heart disease risk in women. The study determined that women who consume diets with a high Glycemic Load are more than twice as likely to develop heart disease than women who eat less of those foods.
We understand the importance of this study, but want to address the critical factors that need to be considered before foods that rate high on the Glycemic Index and enriched grains specifically, are portrayed in a negative light. Carol Pratt, R.D., nutrition counsel for the Wheat Foods Council, analyzed the study and provides the following insights for your consideration.
• While this study does point out the high GL participants were consuming, it fails to detail which food groups provided these carbohydrates (fruits, vegetables, dairy foods, enriched grain products, etc.). Contributing to the high GL, there was excessive consumption of not only carbohydrates, but also calories in this group most at risk for Cardiovascular Heart Disease (CHD). Women in this quartile consumed approximately 335 grams of carbohydrates per day and 2,300 calories, or 22 servings of carbohydrates (assuming 15 g/serving) or 1,340 calories from carbohydrates. The U.S. Dietary Guidelines 2005 recommended calorie intake for women 50 y with a BMI of 26 is approximately 1,500-1,800 with 50% of those calories from carbohydrates (750-900). Women in the highest quartile were exceeding their calorie needs by 27-53%. Women in the lowest quartile consumed more recommended amounts of carbohydrates (230 g), but still higher calories than recommended (2,200).
• Not only were the highest quartile women over-consuming carbohydrates and calories, they were the most physically inactive (46%). Doesn’t inactivity play a role in CHD? The main source of high GL foods contained starch (+72.5% over the first quartile), not sugar (+12.5%) or fiber (+30%) containing food. As mentioned earlier, we don’t know the high GL food group sources.�
• At the same time, total fat and saturated fat levels were 74 and 72% lower in the highest quartile women compared to the lowest quartile. There may be some reason for the highest quartile of GL women to be overcompensating for their reduction in fat with carbohydrates, and from mostly starchy sources. Is this cultural? Were the same data found in each of the five Italian centers? Does the disproportionate consumption of carbohydrates to other macronutrients (protein and fat) predispose CHD?
The Wheat Foods Council emphasizes the importance of a varied, balanced diet with moderate serving sizes that includes many complex carbohydrates, high fiber foods including whole-grains, as well as, fruits, vegetables, lean meat and low fat milk products.
Please feel free to post your comments on this study to our Grain Talk blog.
Submitted by: Carol Pratt, RS, MD, Nutrition consultant for the Wheat Foods Council