Struggling with willpower and concentration? Intermittent fasting may help by changing your gut bacteria
Keep being distracted by food noise? Never have any willpower to do stuff? Here’s why having a digestive break might help.
Since weight loss jabs entered the mainstream, talk of intermittent fasting (IF) seems to have dropped off the radar. But giving your digestive system a bit of a break boasts all kinds of benefits – not least for your gut and brain health. That’s the finding of a new study, which looked into how the body behaves when we reduce our eating window.
Researchers got a small group of obese adults to spend two months doing intermittent fasting and tracked their gut via stool samples. Blood tests were used to monitor metabolic changes, while functional magnetic resonance imaging looked at activity in regions of the brain involved in appetite, emotion, attention, learning, inhibition and reward.
After 62 days, everyone’s blood pressure had fallen, as had cholesterol levels. But, more than that, researchers also found that fasting had reduced the amount of activity in the brain regions responsible for appetite and addiction. They also found that the gut microbiome had changed.
Helpful bacteria like Faecalibacterium prausnitzii, Parabacteroides distasonis and Bacterokles uniformis (all of which help with producing short-chain fatty acids) had massively grown, while strains of E. coli, which can be harmful, sharply decreased. Researchers found that having an abundance of E. coli was negatively associated with activity in the brain’s left orbital inferior frontal gyrus – a region involved with willpower and executive function. That fact led researchers to suggest that intermittent fasting may then help to curb cravings via the gut.
“A healthy, balanced gut microbiome is critical for energy homeostasis and maintaining normal weight,” explained coauthor Dr Yongli Li from the Department of Health Management of Henan Provincial People’s Hospital in Henan, China. “In contrast, an abnormal gut microbiome can change our eating behaviour by affecting certain brain area involved in addiction.”
Large amounts of E. coli reduced willpower
We don’t know yet whether the brain drives microbial change or vice versa but it’s yet more proof of that the gut-brain connection is real and potent. “The gut microbiome is thought to communicate with the brain in a complex, two-directional way. The microbiome produces neurotransmitters and neurotoxins which access the brain through nerves and the blood circulation. In return the brain controls eating behavior, while nutrients from our diet change the composition of the gut microbiome,” said coauthor Dr Xiaoning Wang from the Institute of Geriatrics of the PLA General Hospital.
It’s worth flagging that this study did involve quite extreme intermittent fasting (more along the 5:2 lines) but we do know that even gentle forms of IF (ie having 12 hours between dinner and breakfast) can help with energy, blood sugar and inflammation. Clearly, way more research is needed on the topic with far bigger sample sizes, but it’s a promising step in understand the gut-brain axis all the same.