Intermittent calorie restriction leads to significant changes in both the gut and brain that could open up new opportunities for maintaining a healthy weight
Researchers in China studied 25 volunteers classified as obese over a 62-day period during which they participated in an intermittent energy restriction (IER) program, a program that involves careful control of calorie intake and relative fasting for a few days.
Not only did participants in the study lose weight – an average of 15 pounds, or 7.8% of their body weight – but changes were also observed in the activity of brain regions associated with obesity and in the composition of gut bacteria.
“Here we show that an IER diet alters the human brain-gut-microbiome axis,” said health researcher Qiang Zeng of China’s Second Medical Center and National Clinical Research Center for Geriatric Diseases when the results were published in December 2023.
“The observed changes in the gut microbiome and activity in addiction-related brain regions during and after weight loss are highly dynamic and temporally coupled.”
It is currently not clear what causes these changes and whether the gut influences the brain or vice versa. However, we know that the gut and the brain are closely connected, so treating specific brain regions could be a way to control food intake.
The changes in brain activity detected using functional magnetic resonance imaging (fMRI) occurred in regions known to be important in regulating appetite and addiction, such as the inferior orbitofrontal gyrus.
Bacteria and obesity
In addition, changes in the gut microbiome, analyzed from stool samples and blood measurements, have been linked to specific brain regions.
For example bacteria Coprococcus that you eat And Eubacterium hallii have been negatively associated with activity in the left inferior frontal orbital gyrus, an area involved in executive functions, including our willpower when eating.
“The gut microbiome is thought to communicate with the brain in a complex and bidirectional manner,” explains Xiaoning Wang, a doctor at the China State Geriatric Clinical Center.
“The microbiome produces neurotransmitters and neurotoxins that reach the brain via the nerves and bloodstream. In turn, the brain controls eating behavior, while the nutrients in our diet change the composition of the gut microbiome.”
More than a billion people worldwide are thought to be obese, increasing the risk of a variety of health problems, from cancer to heart disease. Knowing more about the interdependence of our brain and gut could make a big difference in effectively preventing and reducing obesity.
“The next question to answer is the precise mechanism by which the gut microbiome and brain communicate in obese people, even during weight loss,” says biomedical scientist Liming Wang of the Chinese Academy of Sciences.
REFERENCE
Dynamic changes in brain function and gut microbiome during weight loss