Mindless eating: Losing weight without thinking

August 6, 2011

Science Daily/American Psychological Association

Dieters may not need as much willpower as they think, if they make simple changes in their surroundings that can result in eating healthier without a second thought, said a consumer psychologist at the American Psychological Association's 119th Annual Convention.

"Our homes are filled with hidden eating traps," said Brian Wansink, PhD, who presented his findings and strategies for a healthier lifestyle in a plenary address entitled "Modifying the Food Environment: From Mindless Eating to Mindlessly Eating Better."

"Most of us have too much chaos going on in our lives to consciously focus on every bite we eat, and then ask ourselves if we're full. The secret is to change your environment so it works for you rather than against you," Wansink said

Wansink identified several myths about eating behaviors as a way to explain why Americans, on average, have been getting fatter. "People don't think that something as simple as the size of a bowl would influence how much an informed person eats," he said.

However, several studies show exactly that, including Wansink's study of 168 moviegoers, who ate either fresh or stale popcorn from different size containers. People ate 45 percent more fresh popcorn from extra-large containers than large ones and the people who were eating stale popcorn ate 34 percent more from the extra-large buckets than people eating fresh popcorn, according to the study.

They just don't realize they're doing it," said Wansink. This strategy also applies to what we drink. His research found that people pour about 37 percent more liquid in short, wide glasses than in tall, skinny ones of the same volume.

Even a kid's cereal bowl can be a trap, according to Wansink. One study showed children of different weights who were given a 16 ounce bowl were more likely to serve themselves twice as much cereal than children given an 8 ounce bowl.

Another myth, according to Wansink, is that people know when they are full and stop before they overeat. His Food and Brand Lab at Cornell University tested this by designing a "bottomless bowl." They brought in 60 people for a free lunch and gave 22 ounce bowls of soup to half, while the other half unknowingly got 22 ounce bowls that were pressure-fed under the table and slowly refilled. The results: people with bottomless bowls ate 73 percent more than those with normal bowls, yet when asked, they didn't realize they had eaten more. "The lesson is, don't rely on your stomach to tell you when you're full. It can lie," Wansink said.

Simply being aware of such findings can help people make healthier choices, especially those who are already trying to eat healthier foods, according to Wansink. One of his studies showed that people lost up to two pounds a month after making several simple changes in their environment, including:

• ·      eating off salad plates instead of large dinner plates.
• ·      keeping unhealthy foods out of immediate line of sight and moving healthier foods to eye-level in the cupboard and refrigerator.
• ·      eating in the kitchen or dining room, not in front of the television.

"These simple strategies are far more likely to succeed than willpower alone. It's easier to change your environment than to change your mind," Wansink concluded.

http://www.sciencedaily.com/releases/2011/08/110805163541.htm

Sleep Loss Limits Fat Loss

October 5, 2010

Science Daily/University of Chicago Medical Center

Cutting back on sleep reduces the benefits of dieting, according to a study published October 5, 2010, in the Annals of Internal Medicine.

When dieters in the study got a full night's sleep, they lost the same amount of weight as when they slept less. When dieters got adequate sleep, however, more than half of the weight they lost was fat. When they cut back on their sleep, only one-fourth of their weight loss came from fat.

They also felt hungrier. When sleep was restricted, dieters produced higher levels of ghrelin, a hormone that triggers hunger and reduces energy expenditure.

"If your goal is to lose fat, skipping sleep is like poking sticks in your bicycle wheels," said study director Plamen Penev, MD, PhD, assistant professor of medicine at the University of Chicago. "Cutting back on sleep, a behavior that is ubiquitous in modern society, appears to compromise efforts to lose fat through dieting. In our study it reduced fat loss by 55 percent."

Getting adequate sleep also helped control the dieters' hunger. Average levels of ghrelin did not change when dieters spent 8.5 hours in bed. When they spent 5.5 hours in bed, their ghrelin levels rose over two weeks from 75 ng/L to 84 ng/L.

Higher ghrelin levels have been shown to "reduce energy expenditure, stimulate hunger and food intake, promote retention of fat, and increase hepatic glucose production to support the availability of fuel to glucose dependent tissues," the authors note. "In our experiment, sleep restriction was accompanied by a similar pattern of increased hunger and … reduced oxidation of fat."

The tightly controlled circumstances of this study may actually have masked some of sleep's benefits for dieters, suggested Penev. Study subjects did not have access to extra calories. This may have helped dieters to "stick with their lower-calorie meal plans despite increased hunger in the presence of sleep restriction," he said.

The message for people trying to lose weight is clear, Penev said. "For the first time, we have evidence that the amount of sleep makes a big difference on the results of dietary interventions. One should not ignore the way they sleep when going on a diet. Obtaining adequate sleep may enhance the beneficial effects of a diet. Not getting enough sleep could defeat the desired effects."

http://www.sciencedaily.com/releases/2010/10/101004211637.htm