A weight loss secret from the bottomless bowl

When presented with a reasonable-sized portion of food, most people have an approximate expectation of how much of it they intend to consume . For instance, around half of American adults generally claim that they attempt to eat until they "clean their plates." Because portions have grown larger over the years, most people are eating more, without realizing it.

For these people, there is a visual cue or benchmark they have established (a clean plate), and they eat until they either reach that point or until they are otherwise sated. Just as with those people who instead intend to eat one-half or three-quarters of what they are served, all are likely to overconsume if given a larger potion size at the outset.

Some evidence for this comes from a Cornell University research group led by Professor Brian Wansink.

In one study, Wanskink and his team divided subjects into two groups and removed the visual cue — the size of the bowl — for one group. By secretly refilling their bowls through tubes in the bottom, the researchers took away the size of the bowl as a way of helping subjects decide how much to eat.

After 20 minutes everyone quit eating, at which time the group with refilling bowls had consumed almost twice the amount that the other group had. However, they did not believe they had consumed more, nor did they perceive themselves as feeling "fuller" than those eating from normal bowls.

In other words, the subjects could have consumed half the amount they did and still have experienced the same satisfaction.

Although they usually deny it, studies repeatedly show that people eat what's in front of them, using an empty plate — not a full stomach — to tell them when to stop. It seems that people use their eyes to count calories and not their stomachs.

However, just as these cues can lead a person to overeat — as in this study — they may also be used to suppress food intake and help with weight loss. For instance, using smaller plates, bowls, and glasses might lead people to believe they had a full portion and make them less likely to eat more.

Similarly, snack products that are repackaged by a watchful parent into smaller portions and sealed into zip-lock baggies may provide the visual cue that leads a child to believe they've had a full serving of a snack when it was actually a fraction of what they might typically eat.

Just as a smaller-than-average empty bowl of soup can lead people to believe they've had enough to eat, an empty wine bottle on the table may remind guests they have had enough to drink, and the empty peanut shells in front of one person and the empty chocolate wrappers in front of another provide accurate visual cues that they have already had their snacks.

Related Articles

• Belly Fat and How to Beat It
• How to Fight Fat and Win (Members Only)
• The Maximum Muscle Plan (Members Only)
• The Myth about Muscle and Your Metabolic Rate

Reference
Wansink B, Painter JE, North J. (2005). Bottomless bowls: why visual cues of portion size may influence intake. Obesity Research, 13, 93-100