More research is needed to determine the best ways to avoid gaining weight – diet changes can help

Hutfless S, Gudzune KA, Maruthur N, et al.  Strategies to prevent weight gain in adults: A systematic review  Am J Prev Med 2013;45(6):e41–e51

Review question

What are the best ways to prevent weight gain in adults?

Background

Obesity is a leading cause of preventable health problems in North America and worldwide. Avoiding gaining weight is one way to promote a healthy weight among adults and may be a better approach than weight loss, which is hard for people to maintain.

How the review was done

This review included 22 studies that involved a total of 480, 142 participants. Five of these studies focused on older adults (average age 60+). The studies looked at whether diet, exercise, self-management approaches (eg. sleep habits or TV watching) or a combination of all three work best to help people avoid gaining weight.  Any studies of approaches to help people lose or gain weight were not included.

 The studies measured any changes in participants’ body mass index (BMI), weight and/or waist measurements, as well as whether participants kept up the changes, their quality of life and the safety of the approaches (eg. effects on nutrition, injuries or eating disorders). Changes were measured for participants while they were involved in the study and at least 12 months later.  Any changes in weight were compared to a control group of people receiving the usual care. The weight loss approaches were very different in length: the shortest was one 30 minute session with follow-up mailings and phone calls, the longest was 12 years of regular visits.

What the researchers found

It was difficult to make strong recommendations about the best ways to avoid gaining weight.  Although some approaches seemed to help participants avoid gaining weight, the results were often not that different from weight changes of people in the control group.  The authors wondered if people in the control group who did not get advice or support still took extra care to avoid gaining weight, since they knew their weight would be measured. If this is true, perhaps regular weighing can help people maintain their weight.

Some approaches that did help people avoid gaining weight were: 1) eating a low-fat diet; 2) eating out less often; 3) eating more fruits and vegetables; 4) group sessions about lifestyle changes and text message support; 5) monitoring heart rate during exercise. Different approaches worked better for different groups of people.

There were not many high-quality, long-term studies of ways to avoid gaining weight, and none that focused on people who have healthy weights.  Knowing more about the best ways to avoid gaining weight and promoting a number of different methods can help people to choose the approach that works for them.

Conclusion

There is not strong evidence to suggest the best ways to avoid gaining weight. Choosing a low-fat diet, eating out less often, eating more fruits and vegetables, group lifestyle sessions with reminder text messages and monitoring your heart rate during exercise may help.