Obesity changes the brain, with ‘no sign of reversibility’: Study
Obesity may damage the brain’s ability to recognize the sensation of fullness and be satisfied after eating fats and sugars, a new study found.
Further, those brain changes may last even after people considered medically obese lose a significant amount of weight — possibly explaining why many people often regain the pounds they lose.
“There was no sign of reversibility — the brains of people with obesity continued to lack the chemical responses that tell the body, ‘OK, you ate enough,’” said Dr. Caroline Apovian, a professor of medicine at Harvard Medical School and codirector of the Center for Weight Management and Wellness at Brigham and Women’s Hospital in Boston.
As defined medically, people with obesity have a body mass index, or BMI, of over 30, while normal weight is a BMI of between 18 and 25.
“This study captures why obesity is a disease — there are actual changes to the brain,” said Apovian, who was not involved in the study.
“The study is very rigorous and quite comprehensive,” said Dr. I. Sadaf Farooqi, a professor of metabolism and medicine at the University of Cambridge in the UK, who was not involved in the new research.
“The way they’ve designed their study gives more confidence in the findings, adding to prior research that also found obesity causes some changes in the brain,” she said.
The study, published Monday in Nature Metabolism, was a controlled clinical trial in which 30 people considered to be medically obese and 30 people of normal weight were fed sugar carbohydrates (glucose), fats (lipids) or water (as a control). Each group of nutrients were fed directly into the stomach via a feeding tube on separate days.