A new study, published Monday in JAMA Network Open, has found that Americans gained at least 2 pounds per month under COVID-19 shelter-in-place orders in 2020, according to Medscape.

The study has suggested that people who kept the same habits in the lockdown could have gained 20 pounds in the past year.

Senior author Dr. Gregory Marcus of the University of California San Francisco (UCSF) told The New York Times “We know that weight gain is a public health problem in the U.S. already, so anything making it worse is definitely concerning, and shelter-in-place orders are so ubiquitous that the sheer number of people affected by this makes it extremely relevant.”

Dr. Marcus and his team analyzed over 7,000 weight measurements from nearly 270 people in 37 different states who used Bluetooth-connected scales from February 1 through June 1, 2020.

The team found that the volunteers had a steady weight gain of more than half a pound every 10 days, according to Medscape, which equals about 1.5 to 2 pounds per month.

Dr. Marcus told The NY Times that most participants were losing weight before the lockdown orders went into effect.

“It’s reasonable to assume these individuals are more engaged with their health in general, and more disciplined and on top of things,” he added. “That suggests we could be underestimating — that this is the tip of the iceberg.”

The authors said the study was conducted on a small scale so it does not represent the entire nation. They also said it cannot be generalized to the U.S. population, but it is a sign of what is happening during the COVID-19 pandemic.

The team explained that the volunteers’ weight increased irrespective of their location and chronic medical conditions, according to Medscape.

Another study conducted by the researchers of UCSF found that people do not move around as much during lockdowns. The study was published in the Annals of Internal Medicine in November 2020.

Referring to smartphone data, the researchers found that daily step counts decreased by 27% in March 2020, when there was a strict lockdown. The step counts increased again throughout the summer but still remained lower than before the COVID-19 pandemic, according to Medscape.

The authors of the study published in JAMA Network Open wrote, “The detrimental health outcomes suggested by these data demonstrate a need to identify concurrent strategies to mitigate weight gain, such as encouraging healthy diets and exploring ways to enhance physical activity, as local governments consider new constraints in response to SARS-CoV-2 and potential future pandemics.” The story originally appeared Tuesday on Medscape Medical News.