An interesting publication from the Journal of the Academy of Nutrition and Dietetics suggests that we are not very good at judging portion sizes of our cereal.
The researchers gave volunteers corn flakes once a week for 4 weeks and allowed them to choose their portion size and to eat as much of it as they wanted. Corn flakes of different sizes were given by crushing to generate flakes of 80%, 60% and 40% of the original size.
When given the more crushed corn flakes, the volunteers consumed more despite believing they had had the equivalent. They recognised that the flakes were smaller and so took less but they still took more by weight than when the flakes were whole.
On average the calories consumed increased from 286 to 358 kcal, that is an increase of 25%.
So, my question is, if the effect works when the flakes are made smaller, can it be exploited in the other direction. When can we expect to see giant corn flakes in the supermarkets?
The paper is available from the Journal of the Academy of Nutrition and Dietetics website.