Cereal flake size influences calorie intake

http://feeds.feedburner.com/~r/sciencedaily/living_well/~4/BbEDFg8I0Po

People eat more breakfast cereal, by weight, when flake size is reduced, according to Penn State researchers, who showed that when flakes are reduced by crushing, people pour a smaller volume of cereal into their bowls, but still take a greater amount by weight and calories.”People have a really hard time judging appropriate portions,” said Barbara Rolls, professor of nutritional sciences and Helen A. Guthrie Chair in Nutrition. “On top of that you have these huge variations in volume that are due to the physical characteristics of foods, such as the size of individual pieces, aeration and how things pile up in a bowl. That adds another dimension to the difficulty of knowing how much to take and eat.”According to Rolls, national dietary guidelines define recommended amounts of most food groups in terms of measures of volume such as cups.”This can be a problem because, for most foods, the recommended amounts have not been adjusted for variations in physical properties that affect volume, such as aeration, cooking, and the size and shape of individual pieces.” Rolls said. “The food weight and energy required to fill a given volume can vary, and this variation in the energy content of recommended amounts could be a challenge to the maintenance of energy balance.”The researchers tested the influence of food volume on calorie intake by systematically reducing the flake size of a breakfast cereal with a rolling pin so that the cereal was more compact and the same weight filled a smaller volume. In a crossover design, the team recruited 41 adults to eat cereal for breakfast once a week for four weeks. The cereal was either standard wheat flakes or the same cereal crushed to reduce the volume to 80 percent, 60 percent or 40 percent of the standard. The researchers provided a constant weight of cereal in an opaque container and participants poured the amount they wanted into a bowl, added fat-free milk and non-calorie sweetener as desired and consumed as much as they wanted.The researchers reported their results in the current issue of the Journal of the Academy of Nutrition and Dietetics.The research showed that as flake size was reduced, subjects poured a smaller volume of cereal, but still took a significantly greater amount by weight and energy content. Despite these differences, subjects estimated that they had taken a similar number of calories of all versions of the cereal. They ate most of the cereal they took, so as flake size was reduced, breakfast energy intake increased.”When faced with decreasing volumes of cereal, the people took less cereal,” Rolls said. …


Read More: Cereal flake size influences calorie intake