Read more

July 26, 2021
2 min read
Save

Early decrease in weight loss during COVID-19 pandemic did not persist long term

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact customerservice@slackinc.com.

U.S. adults participating in a digital weight-management program lost less weight in the first 7 weeks of the COVID-19 pandemic vs. participants from a year prior, but the changes did not persist long term, according to study data.

Gary Foster

“This is probably the largest study of a digital weight-management program ever,” Gary Foster, PhD, chief scientific officer at WW (formerly Weight Watchers), told Healio. “It’s a novel look at how a major environmental stressor like COVID can impact a weight-loss journey.”

Weight loss scale and tape measure 2019
Source: Adobe Stock

Foster and colleagues analyzed data from participants in WW’s digital weight-management program who joined in the first 30 weeks of 2020 (n = 866,192). Data from 2020 participants were compared with data from those who joined in the first 30 weeks of 2019 (n = 624,043). Weight change and self-monitoring of weight, food and activity in the app were assessed during the first 4 weeks of membership for each participant. All data were self-reported as they were entered in the app. The study’s findings were published in Obesity.

From the week of March 8 to the week of April 19, 2020, WW members had significantly less weight loss compared with 2019. For the week of March 8, participants lost 0.67 percentage points less weight in 2020 compared with 2019. That difference increased to 1.18 percentage points for the week of March 15 and 1.24 percentage points for the week of March 22, before gradually decreasing. In the 23 weeks after the week of April 19, there was no significant difference in weight loss in 2020 compared with 2019.

WW members reported fewer days of food self-monitoring from the week of March 8 to the week of March 22, 2020, compared with the previous year. There were no significant differences in food tracking before the COVID-19 pandemic and after the week of March 22. Days in which participants used self-monitoring of weight and activity were not significantly different in 2020 compared with 2019.

Foster said the abrupt change to everyday routines in the opening weeks of the COVID-19 pandemic may have been responsible for the difference in weight loss compared with the previous year.

“It’s multifactorial,” Foster said. “You have the actual stress and the uncertainty of the pandemic. A lot of people eat in response to stress. You also have the anxiety in the initial weeks of this study, the uncertainty of what COVID-19 was going to do.”

Despite the short-term weight-loss effect, Foster said the lack of a difference in weight loss long term during the pandemic showed how WW participants were able to adapt to changes as well as the strength of the digital weight-management program’s method.

“It gives people a great degree of comfort that they can rely on proven strategies no matter what the context,” Foster said.

For more information

Gary Foster, PhD, can be reached at media@ww.com.