Weight Loss Through Surgery May Improve Memory, Cognition: Study

April 17, 2011 Updated: September 29, 2015


Bariatric surgery, or weight loss surgery performed on those who are obese, may improve patients’ cognitive ability and memory, with noticeable results coming 12 weeks after surgery, new research published online in the journal Surgery for Obesity and Related Diseases suggests.

“Going through this surgery, individuals might improve their memory, concentration and problem solving,” Kent State University researcher John Gunstad said in a university press release. “It might be an opportunity for individuals who have memory or concentration problems to make those things better in a short amount of time.”

The study followed 150 participants—109 who had underwent bariatric surgery and 41 obese subjects who did not undergo the surgery and were thus the control group—at two university medical centers in New York City and one institute in Fargo, N.D. The bariatric surgery patients performed better on cognitive tests 12 weeks after their operation, improving their results from “slightly impaired” to “normal.”

“One of the things about obesity, relative to other medical conditions, is that something can be done to fix it,” Gunstad noted “Our thought was, if some of these effects are reversible, then we’re really on to something.”

Gunstad, who worked with researchers from Cornell Medical College and Weill Columbia University Medical Centerin New York, Warren Alpert Medical School of Brown University, University of Missouri-St. Louis, and the Neuropsychiatric Research Institute in Fargo, N.D., said that obese patients incur other risk factors that harm parts of the brain that affect cognition.

“As those problems go away, memory function gets better,” Gunstad argued.

Exercise regiments can also help to improve memory and concentration, Gunstad said.

“One of the things we know is that as individuals become more cardiovascular fit and their heart health gets better, their brain health also improves,” he noted. “Even if we take young adults and put them through an exercise program, their memory and their concentration get better by the end of the program.”

Gunstad added that he expects to see similar results among patients who have lost weight without bariatric surgery, which is the team’s next project.

The National Institute of Health, a government institution, funded the research, providing the team with $1.5 million.