Aug. 3, 2012 at 8:19 AM ET
People who lose the most weight may be those who can overcome urges when they see, smell or dream about something tasty, researchers said this week. And their study adds to a growing body of evidence that another key to success is keeping a food diary.
The intensive study of more than 100 dieters showed that those who could overcome so called "hedonic hunger" -- appetite linked to outside cues such as smelling bread baking -- lost the most weight. It’s not clear which came first, cautions Patrick O’Neil, a professor and director of the weight management center at the Medical University of South Carolina, who led the study. Was it the weight loss, or the ability to control the urges?
“People who lost more weight also reported a greater drop in hedonic hunger,” O’Neil said. He said it is possible that losing weight has the beneficial side-effect of helping people control those urges.
Keeping unhealthy food out of sight and out of mind may be key, O’Neil’s team said. “Considering that decreases in hedonic hunger were associated with an improvement in reported weight control behavior usage as well as with better weight loss, strategies for controlling the type and quantity of food available in the home environment may be particularly important for individuals who report high susceptibility to the food environment,” the researchers wrote.
In other words, steer physically clear of unhealthful foods high in fat, sugar and calories.
“Changing specific behavior makes a difference,” O'Neil said in a telephone interview. “It’s not just enough to say ‘eat less and exercise more’. There are specific things that you can do to make it easier for you to eat less.”
O’Neil’s team studied 111 men and women aged 25 to 65 who were, on average, obese, with a body mass index (BMI) of about 31. People are considered medically obese when their BMI hits 30 -- a person 5 feet 5 inches tall is overweight at 150 pounds and obese at 170 pounds.
The study was paid for by Weight Watchers, and the dieters all went on the Weight Watchers program, which includes weekly group meetings, regular weigh-ins, keeping food diaries and assigning values to different foods to control fat, fiber and sugar.
The volunteers filled out questionnaires before they started the three-month program. One, called the Power of Food Scales, asked dieters to agree or disagree with statements such as: “I find myself thinking about food even when I'm not physically hungry,” “If I see or smell a food I like, I get a powerful urge to have some,” and “Just before I taste a favorite food, I feel intense anticipation.” It measures hedonic hunger.
A second questionnaire looked at what the dieters did to control their eating, such as leaving food on the plate, keeping fresh vegetables around to snack on, or refusing food. People who answered yes to these three questions: “I carefully watch the quantity of food which I eat,” “I record the type and quantity of food which I eat,” “I keep one or two raw vegetables available for snacks” tended to lose more weight.
Everyone was encouraged to walk daily and to attend weekly meetings.
The program worked. Other studies have also shown Weight Watchers is one of the most successful commercial weight loss programs. Over the 12 weeks, the 111 volunteers who made it all the way through the program lost an average of eight pounds. ”A reduction in body weight of at least 5 percent was seen among 42 percent of the subjects,” the researchers write in an upcoming issue of the journal Eating Behaviors. The dieters answered the same quizzes again at the end of the 12 weeks.
“A decrease in hedonic hunger (Power of Food Scales total score) was associated with greater percent weight loss, “ O’Neil’s team wrote. “To our knowledge, the present study is the first to report changes in hedonic hunger with a weight loss program, and an association of some of those changes with weight loss,“ they added.
The single best indicator of whether a person had lost weight was if they reported better control of eating if they merely thought about a food, the researchers said. But the food diary helps on several levels, O’Neil said. “It will instruct you as to what your current patterns are,” he said. “It can open your eyes to what you are actually consuming, and also show you some low-hanging fruit -- the easiest calories you can dispense with.”
Last week, a team reported in the Journal of the Academy of Nutrition and Dietetics that women who kept consistent food journals lost more weight than women who didn't.