Keeping the pounds off

January 2013 - It is a sad and frustrating fact that many (perhaps, most) attempts to lose weight result in a temporary loss that is reversed in a relatively short time.

Viviana F. Bumaschny, M.D., assistant investigator of CONICET (Argentina) and researchers at the University of Michigan have shed light in the Journal of Clinical Investigation on why the weight comes back. Using mice as a model they found that the longer mice remained overweight, the more "irreversible" the obesity became.

According to senior author Malcolm J. Low, M.D., Ph.D., professor of molecular and integrative physiology and internal medicine, the obese state resets the "normal," body weight set point to a permanently higher state despite diets that shed pounds initially:

"Somewhere along the way, if obesity is allowed to continue, the body appears to flip a switch that re-programs to a heavier set weight. The exact mechanisms that cause this shift are still unknown and require much further study that will help us better understand why the regaining of weight seems almost unavoidable."

"Our model demonstrates that obesity is in part a self-perpetuating disorder and the results further emphasize the importance of early intervention in childhood to try to prevent the condition whose effects can last a lifetime."

Mice that never overeat and remain at a healthy weight into young adulthood are able to maintain normal weight without dieting but chronically overfed mice with early onset of obesity can never completely return to normal weight after 'flipping the switch', despite reduced food intake and increased activity.

However there is older research that is more hopeful. A 2006 study in the New England Journal of Medicine showed that weighing yourself every day, cutting calories and boosting exercise when the numbers are too high can significantly help maintain your weight loss. The study, by Miriam Hospital and Brown Medical School researchers, provides results from the first program claimed to be designed specifically for weight loss maintenance. .

Most weight-loss studies focus on how to lose unwanted pounds. The 'STOP Regain' clinical trial described in this study tested a method of teaching dieters how to keep the weight from coming back, no matter how they lost the weight in the first place. The study was led by Rena R.Wing, PhD, Director of the Weight Control and Diabetes Research Center at The Miriam Hospital and Professor of Psychiatry and Human Behavior at Brown Medical School. Her team included Deborah Tate, PhD, assistant professor in the School of Public Health at the University of North Carolina -Chapel Hill, Amy Gorin, PhD, Hollie Raynor, PhD, and Joseph Fava, PhD, of The Miriam Hospital and Brown Medical School.

Dieters were taught a technique called "self-regulation' that had a goal of maintaining participants' weight within five pounds. They were asked to weigh themselves every day and use that information to decide to adjust their diet or exercise routine. The result was that significantly fewer participants in the study put five or more pounds back on during the 18 month long program. The researchers found that the program worked best when delivered in face-to-face meetings but the Internet was also a viable delivery system to help dieters maintain their weight loss.

"If you want to keep lost pounds off, daily weighing is critical," said Rena Wing. "But stepping on the scale isn't enough. You have to use that information to change your behavior, whether that means eating less or walking more. Paying attention to weight - and taking quick action if it creeps up - seems to be the secret to success."

"We know that losing weight and keeping weight off is very tough for many people," said Robert J. Kuczmarski, Dr. P.H., R.D., director of the Obesity Prevention and Treatment Program at the National Institutes of Health. "However, the results of STOP Regain show that there are definite actions that people can take before their weight begins to creep upward. Weight control and better health are not one-shot deals and this study will help people see that."

What did the study involve? 314 participants were selected who had lost at least 10% of their body weight in the last 2 years. In fact, they averaged a loss of 42 pounds - almost 20% of their body weight. One third were allocated to a control group, receiving a quarterly newsletter in the mail about eating and exercise.

The remaining two-thirds were allocated to testing the weight maintenance program with the first third receiving the intervention by means of the Internet and the final third taking part in face-to-face group meetings. Both these groups were provided with virtually identical education and support. They attended weekly meetings for the first month of the study and then monthly meetings. The face-to-face participants met in groups while the Internet participants met via a computer chat room. The Internet participants were each given a laptop computer, an Internet connection and technical support.

Participants were taught a number of strategies designed to prevent the pounds being regained, including:

• eating breakfast
• being physically active for an hour every day
• weighing themselves regularly - they were given scales to use daily.

Participants were asked to report their weight weekly, either through the Internet or by telephone, depending on the group they had been allocated to. They also used a color zone weight-monitoring system:

1. The green zone for those within three pounds of their starting weight after a weekly report. They received encouraging messages by phone and 'green rewards' such as mint gum or a dollar bill.
2. The yellow zone for participants who had gained between three and four pounds. They were asked to modify their eating habits or exercise routine.
3. The red zone where people had gained five pounds or more. These participants were encouraged to engage in active weight-loss efforts and were urged to make use of a red toolbox they were given at the beginning of the program. The toolbox included items such as:
• a meal replacement shake
• a pedometer
• a diet diary, and
• their own weight success loss story.

People in the "red zone" were also given the opportunity of one-on-one counseling by phone, email or in person.

What were the results of the study? 72% of people in the control group gained five or more pounds during the year and a half of the study compared to only 55% of the Internet group and 46% of those in the face-to-face group.

Rena Wing commented: "The Internet intervention worked, but the face-to-face format produced the best outcomes. Both were successful because the message that people got - pay attention to your weight, then take action to maintain it - was effective. People were told to take personal control of their health and were given the tools to do it. And they kept off the weight."

Intriguingly, while daily weighing for the Internet and face-to-face groups reduced the likelihood of regaining five or more pounds by 82%, there was little effect for the control group.

"This suggests that participants in the intervention groups were able to use the information from the scale to make constructive changes in their eating and exercise behaviors," said Wing. "It's further evidence that getting on the scale each day is only part of the solution."