Answer : We went back to our oatmeal expert, Cynthia Harriman, director of food and nutrition strategies for The Whole Grains Councilwww.WholeGrainsCouncil. org, who confrms that steel-cut oats have a lower glycemic index (GI)-a measure of how quickly carbohydrates affect blood sugar-than rolled oats. The reason? In general, foods that are processed into smaller particles have a higher glycemic index than the same food in a less processed form, and this is true of oatmeal, too. Rolled oats (which include regular, quick and instant) are steamed, rolled and cut into thinner pieces than steel-cut oats. She cites an interesting 1999 study in which researchers fed either instant oatmeal or steel-cut oats to a group of obese teens: The teens consumed 53% more calories in the five hours after eating a high-GI instant oatmeal breakfast than after eating medium-GI steel-cut oats.
