The number of people who were hospitalized for eating disorders in the United States doubled during the COVID-19 pandemic, new research shows.
The increase in in-patient treatment for eating disorders came as early as May 2020, according to researchers from the University of Pennsylvania, whose study was published Monday in JAMA Network Open.
Rising cases were seen across anorexia nervosa, bulimia nervosa and unspecified eating disorders, according to the study.
The researchers attributed the increased rates of hospitalization to several factors, including the conditions of the pandemic that may have promoted eating disorder behaviors, such as grocery shopping being a more "fraught" experience and the fact that schools and colleges were closed, which may have led to covert eating disorder symptoms being caught by families in close quarters.
MORE: My eating disorder thrived during the pandemic: COVID-19 quarantine sparks concern of eating disorder crisisA delay in outpatient care may have also led to increased hospitalizations, according to the researchers.
Data has previously shown the pandemic has brought on a mental health crisis in the U.S., of which eating disorders are a major part.
Throughout the pandemic, the National Eating Disorder Association (NEDA) said it has seen a spike of more than 70% in the number of calls and online chat inquiries to its hotline compared to the same time period in 2019.
"This has been a time of heightened anxiety for everyone," NEDA's CEO Claire Mysko told "Good Morning America" last year. "For people with eating disorders, either those who are actively struggling or those who are pursuing recovery, there's an added stressor with the pandemic."
The Emily Program, a national network of eating disorder treatment centers, has seen inquiries both online and by phone "fly off the charts" during the pandemic, Dr. Jillian Lampert, the Emily Program's chief strategy officer, also told "GMA."
MORE: Women speak out to break eating disorder stereotypes amid pandemic surgeThe nature of the pandemic, with its uncertainty and isolation, makes it a situation that "checks every box" for putting people at a higher risk for eating disorders, according to Lampert.
"We're seeing people calling now in a more acute, intense stage [of an eating disorder]," Lampert said last year. "So we're seeing not only are more people calling, but more people are calling in a more crisis situation."
Eating disorders have remained second only to opioid overdose as the deadliest mental illness throughout the pandemic, with eating disorders responsible for one death every 52 minutes in the U.S., according to data shared by the National Association of Anorexia Nervosa and Associated Disorders.
Nearly 30 million Americans will have an eating disorder in their lifetime, according to the association.
If you or someone you know is battling an eating disorder, contact the National Eating Disorders Association (NEDA) at 1-800-931-2237 or NationalEatingDisorders.org.