New research tests a novel strategy for preventing holiday weight gain and proposes a psychological mechanism that explains why the strategy may work.

More than 37% of adults in the United States are living with obesity, estimates show, and experts expect this number to increase. More than 32% of US adults are overweight. Research shows that on average, people gain between 0.4 and 1 kilogram (kg) of weight per year. Although this may be a small amount, persistent weight gain can lead to obesity over time. Most of us are familiar with the so-called holiday weight gain. During mid-November and January, adults tend to gain 0.4–1.5 kg, on average. Now, research appearing in the journal Obesity suggests that weighing ourselves every day could be an effective way to prevent weight gain. Jamie Cooper, PhD, who is an associate professor in the Department of Foods and Nutrition at the University of Georgia in Athens, led the new research.

Studying a new weight loss strategy

For their study, Cooper and colleagues recruited 111 adults who were 18–65 years old. The participants weighed themselves with varying degrees of frequency between mid-November 2017 and early January 2018. The researchers asked the participants to complete three visits: one just before the holiday season, another one immediately after, and the third one 14 weeks after the intervention. Cooper and team also asked the participants to use a Likert scale to assess the frequency with which they weighed themselves.

During the intervention, the researchers asked the participants to try to maintain their initial weight throughout the study period, but they did not offer them any advice on how to do this. So, each participant was free to choose whatever method they wished, whether it involved exercising or dieting. The researchers compared these participants with a control group who did not receive any instructions at all.

At the end of the study period, those who weighed themselves every day and got a graphical representation of their weight changes either maintained the same weight they had at baseline or lost weight.

"Maybe they exercise a little bit more the next day (after seeing a weight increase), or they watch what they are eating more carefully," comments Cooper. "The subjects self-select how they are going to modify their behavior, which can be effective because we know that interventions are not one size fits all." In contrast, participants who did not self-weigh every day gained weight.

Self-perception is key for weight loss

Study co-author Michelle vanDellen, who is an associate professor in the Department of Psychology at the University of Georgia, explains the psychological mechanisms that might be at play behind these results.

"People are really sensitive to discrepancies or differences between their current selves and their standard or goal," vanDellen says. "When they see that discrepancy, it tends to lead to behavioral change. Daily self-weighing ends up doing that for people in a really clear way."

The authors are not sure whether daily self-weighing without the graphical representation would have the same effect. "[R]eplication in larger studies with more diverse participants would help to determine the generalizability of this approach for weight gain prevention," comments Dr. Susan Yanovski, an obesity researcher at the National Institute of Diabetes and Digestive and Kidney Diseases.

"Vacations and holidays are probably the two times of year people are most susceptible to weight gain in a very short period of time," lead author Cooper concludes. "The holidays can actually have a big impact on someone's long-term health."