Losing weight by intermittent fasting can ‘drastically change’ the way your brain works

Into intermittent fasting? Tinkering around with the trendy weight loss method touted by celebs like Jennifer Aniston, Kourtney Kardashian and Gwyneth Paltrow could be messing with your brain, a new study shows.

Researchers at the Health Management Institute in Beijing found that intermittent energy restriction (IER) can lead to dramatically changed gut bacteria and brain activity, with both positive and negative effects, South West News Service first reported.

The diet involves alternating days of fasting, or something close to it, with days of normal eating. Study participants lost an average of about 16 lbs. over a period of two months.

Intermittent fasting has been criticized repeatedly for its alleged risks, ranging from Type 2 diabetes to increased likelihood of death.

Once the IER portion of the study was completed, participants showed “decreases in the activity of brain regions implicated in the regulation of appetite and addiction.”

Also demonstrated: “an increase in abundance of certain gut bacteria that can help with attention, motor inhibition, emotion and learning.”

“Here we show that an IER diet changes the human brain-gut-microbiome axis,” said the HMI’s Dr. Qiang Zeng.

“The observed changes in the gut microbiome and in the activity in addition-related brain regions during and after weight loss are highly dynamic and coupled over time.”

The results were achieved by studying stool samples from 25 Chinese men and women on an IER diet.

Participants first went through a 32-day “high-controlled fasting phase,” where they ate dietician-designed meals personalized to their needs.

After that, the human guinea pigs spent 30 days in what’s called a “low-controlled fasting phase” — in which they were allowed to make more of their own choices.

Newly published in Frontiers in Cellular and Infection Microbiology, the study also suggests that the weight-loss method can help to reduce issues related to obesity such as hypertension, hyperlipidemia and liver dysfunction.

Some negative side effects were noted, however, particularly to the executive function, which would impact our will to lose weight.

“A healthy, balanced gut microbiome is critical for energy homeostasis and maintaining normal weight,” said Dr. Yongli Li, also from the Department of Health Management.

“In contrast, an abnormal gut microbiome can change our eating behavior by affecting certain brain areas involved in addiction.”

“The next question to be answered is the precise mechanism by which the gut microbiome and the brain communicate in obese people, including during weight loss,” added Dr. Liming Wang of the Institute of Microbiology, Beijing.

“What specific gut microbiome and brain regions are critical for successful weight loss and maintaining a healthy weight?”