When will you eat a cup of food that is half the calories of another cup of that same food? When that food is made of larger, fluffier pieces, suggests a new study.
The study, published in the Journal of the Academy of Nutrition and Dietetics, focused on breakfast cereals. By eating flakes that were larger and took up more space in the bowl, people ate 100 calories less for breakfast than when eating the smaller, denser flaked cereal.
The findings relate to AICR’s recommendation for cancer prevention on eating mainly plant foods, which are low in calorie (energy) density. Bite for bite, many vegetables and other plant foods contain relatively few calories. That can help with weight control, which in turn reduces cancer risk. In the study, each week for four weeks, 41 breakfast eaters were offered 10 ounces (280 grams) of Wheaties.
Unbeknownst to them, the flake size was changed. One week they were served the cereal as packaged, considered the standard. The other three weeks they were given cereals where the flakes were crushed to 80%, 60% or 40% of the standard. As the flakes got smaller, the cereal took up less room in the bowl. Participants filled their own cereal bowls and could eat as much as they wanted. On average, people ate 102 more calories when eating the smallest flake compared to the standard. That occurred even though the participants ate almost half the amount of the smallest flakes compared to the largest.
With the standard Wheaties they ate almost 2 cups; the smallest size flake they ate slightly over 1 cup. Yet the breakfast eaters estimated they were eating about the same calories for each meal, underestimating the calories from the two smallest flaked Wheaties.
The findings have implications for dietary advice, conclude the authors. In the same way that government recommendations say two cups of raw leafy greens equals about a cup of the standard vegetable portion, servings sizes for denser cereals could change depending upon its physical properties.