Trick the mind into satisfying the belly

WASHINGTON - The key to weight loss could lie in tricking our mind into thinking about how filling the food will be before we eat it.

Test subjects were more satisfied for longer periods after consuming varying quantities of food for which they were led to believe that portion sizes were larger than they actually were.

Memories about how satisfying previous meals were also played a causal role in determining how long those meals staved off hunger.

“The extent to which a food that can alleviate hunger is not determined solely by its physical size, energy content, and so on,” said Jeff Brunstrom, reader in behavioural nutrition, University of Bristol, Britain, who led the study.

“Instead, it is influenced by prior experience with a food, which affects our beliefs and expectations about satiation.”

“This has an immediate effect on the portion sizes that we select and an effect on the hunger that we experience after eating,” added Brunstrom.

In the first experiment, participants were shown the ingredients of a fruit smoothie. Half were shown a small portion of fruit and half were shown a large portion, according to a University of Bristol statement.

They were then asked to assess the “expected satiety” of the smoothie and to provide ratings before and three hours after consumption.

Participants who were shown the large portion of fruit reported significantly greater fullness, even though all participants consumed the same smaller quantity of fruit.

In a second experiment, researchers manipulated the “actual” and “perceived” quantity of soup that people thought that they had consumed.

Using a soup bowl connected to a hidden pump beneath the bowl, the amount of soup in the bowl was increased or decreased as participants ate, without their knowledge.

Three hours after the meal, it was the perceived (remembered) quantity of soup in the bowl and not the actual amount of soup consumed that predicted post-meal hunger and fullness ratings.