Research demonstrating changes in the brain and gut microbiome during weight loss was conducted in China with a group of 25 volunteers. The participants underwent meticulous brain and gut examinations during a 62-day period while following a weight loss diet, which involved a strictly regulated calorie intake and fasting on certain days (Intermittent Energy Restriction, IER). IER is defined as periods of restricted calorie consumption followed by periods of normal intake. The research showed that a long-term diet like IER, lasting over three months, is an effective weight loss strategy.
Observations revealed that participants not only lost a significant amount of weight (an average of 7.6 kg), but their gut microbiome composition also changed. However, that wasn’t all - brain imaging using fMRI (functional magnetic resonance imaging) showed changes in the activity of areas linked to obesity.
Gut Microbiome Changes and Brain Changes
Scientists believe that intermittent fasting alters the human brain-gut-microbiome axis. They explained:
Changes in brain activity, detected through fMRI scans, occurred in areas known to be important in regulating appetite and addiction.
Additionally, analysis of stool and blood samples showed that changes in gut flora were associated with changes in specific areas of the brain. Researchers suggest that the gut microbiome communicates with the brain in a complex, bidirectional way.
The microbiome produces neurotransmitters and neurotoxins that reach the brain through nerves and circulating blood. In return, the brain controls eating behaviors, while nutrients in our diet alter the composition of the gut microbiome
- said Xiaoning Wang, co-author of the study.
It is not yet known what causes these changes or whether the gut influences the brain or vice versa. One thing is clear: a connection between the brain and the human gut microbiome exists. Therefore, a change in one area can trigger a change in the other, meaning that treatments targeting specific brain areas may help improve gut function, researchers argue.
Now, scientists aim to understand more about how the gut and brain communicate in obese individuals to identify ways to treat or support these people during weight loss. Obesity is currently one of the biggest health challenges worldwide. The research was conducted at the Second Medical Center and National Clinical Research Center for Geriatric Diseases in China, and the findings were published in the journal Frontiers in Cellular and Infection Microbiology.
