It's not just what you eat, it's how you eat

Obesity is often blamed on eating high-fat, high-sugar, non-nutritious foods. But the manner in which one eats may play an important role in body weight, too.

A study published online today in the British Medical Journal found that people who said they eat quickly and eat until full were three times more likely to be overweight than people who said they don't eat quickly and don't eat until they are full. The study surveyed more than 3,000 Japanese men and women about their eating habits. The researchers defined "eating until full" as consuming a large quantity of food in one meal. (This is not the same thing as gorging or binge eating.) The researchers concluded that eating quickly and eating until full "has a supra-additive effect on overweight" regardless of the food eaten.

There is little research to help explain what drives people to eat quickly or eat until full. It's possible, the researchers suggest, that changes to society have influenced how we eat, such as fewer families eating meals together at home, more people eating while distracted, more people eating fast food and greater access to inexpensive, energy-dense food served in large portions.

The solution? Studies show that people can learn to eat slowly and eat less. Families should focus on serving appropriate portions of food and eating in a non-distracting environment, said the lead author of the study, Dr. Hiroyasu Iso, from Osaka University in Japan.

-- Shari Roan

Photo: Competitive eaters participate in a 2008 contest in New York City. Credit: Rhonda Vanover / Getty Images.

Comments

[tarbubble]

this is intriguing. if i make the mistake of bringing home something like a bag of potato chips you can bet i'll eat half of the bag in a day - but it does take me all day, as i am a grazer. if i'm actually sitting down to a meal, i make an effort to have it be a healthy meal. my point? i'm not overweight at all, even though i recognize that i probably take in more calories per day than i ought to in order to maintain my weight. i've always figured that i must have a high metabolism, but now i wonder if it's my eating patterns that are helping me keep a respectable weight. hmm, i should go eat some snap peas now, and not raid the potato chips.

[John B]

Whoever funded this study should ask for their money back.

[L. Cid]

I sometimes eat with my mouth open, that is I get caught eating with my mouth open. Could that affect how I gain or lose weight? Does sound affect eating and weight? If I occaissionally clack my fork against my teeth, does that increase or decrease weight?
Just checking.

[Erik Ostermueller]

So fast eating and obesity are correlated with each other. Understood. However, that is completely different than having a cause-effect relationship.

If such a cause-effect relationship did exist, it sure seems that it would be inconsistent with the law of conservation of mass and energy.
This would raise the bar for the amount of proof that it would take to prove such a relationship.

[Mark Roberts]

I tend to eat very quickly and not chew my food very well. I've never even reached the level of "chubby", let alone overweight.

There is no science behind the claim that eating slowly makes you less liklely to be overweight; on the contrary. Carbohydrates are digested mainly by saliva. The slower you eat and the longer you chew, the more energy you'll absorb from them later.

Of course, if people in one group "eat until they're full" and people in the other group don't, then the people who ate until they were full (ie, the ones who ate more) are more likely to be overweight. Is anyone surprised?

[Dan]

This study if from Britain. If we had crappy food like they have in Britain we'd be thin too.

[andre]

There is only one diet that works. If it taste good spit it out

[Curtis Fong]

This study was a survey of Japanese people, not British. Grazing throughout the day is better than eating a few meals until full as the body does not enter "starvation mode" where it aggressively stores food as reserves for future use. Eating many small meals helps the body burn the food throughout the day.