Recent research suggests that shedding pounds through a method known as intermittent energy restriction (IER) can not only help with significant weight loss but also encourage notable changes in the gut microbiome as well as enhance brain activity. All of this, taken together, can potentially aid in sustained weight loss efforts.
In this recent study, researchers closely examined stool samples, blood measurements, and functional magnetic resonance imaging (fMRI). All three of these when taken together show the alterations in gut microbiome and brain activity in 25 Chinese individuals with obesity undergoing an IER diet. The participants, with an average age of 27 and a body mass index (BMI) between 28 and 45, engaged in alternating periods of eating in a calorie deficit and eating at maintenance calories.
Thus, the study was limited in both scope and duration. However, it is encouraging for people who have struggled with obesity and long-term changes in their eating habits for the kind of prolonged weight loss those suffering from obesity need.
Throughout the study, participants were subject to a high-controlled fasting phase for 32 days, reducing their caloric intake by one-quarter of their basic energy intake. This was then followed by a 30-day “low-controlled fasting phase.” By the study’s conclusion, participants had achieved an average weight loss of 7.6 kilograms (a little over 16 pounds), equivalent to approximately 7.8%. The study also noted a decrease in the activity of brain regions associated with appetite regulation and addiction.
Examining the gut microbiome, researchers observed a significant increase in the abundance of healthy bacteria, while unhealthy bacteria decreased. Notably, the abundance of certain healthy bacteria correlated positively with brain regions linked to attention, motor inhibition, emotion, and learning. Conversely, the reduction in E. coli, a significant finding, was associated negatively with brain regions crucial for executive functions, including the determination to lose weight.
While there should be little surprise at the substantial weight and body fat percentage reduction, due to caloric restriction, the impact on both gut health and brain function was an intriguing shock to researchers. This underscores the unexpected influence of food intake restriction on specific brain activities, as well as buttresses the beliefs of many who have touted gut health’s role in brain functioning for years now.
Indeed, the study’s results align with an evolving understanding of the intricate relationship between the gut, the brain, and weight management. Lifestyle interventions, such as IER, can begin synchronized changes across the brain-gut-microbiome axis. This shows that there is a virtuous cycle of sorts when it comes to getting just one of these areas squared away.
The reasons behind the observed effects of IER on the gut microbiome and brain activity is slightly more obscure. However, initial research reveals a bidirectional communication link between the gut and the brain. As the body shifts from using glucose to metabolizing stored fats during fasting, hormonal and neurotransmitter activity undergoes alterations, influencing brain regions related to appetite, motivation, and addiction. Simultaneously, the gut microbiome, responsive to dietary changes, produces signaling molecules that impact the brain, leading to a synchronized response across the brain-gut-microbiome axis.
While serotonin, a hormone known to regulate appetite and mood, may play a role in these changes, further research is needed to explore the intricate mechanisms at play. Again, the research study was very limited and, at the very least, a wider and longer-duration study will be needed to even verify the results of this first study.
For those interested in trying IER, a gradual approach is best, starting with shorter fasting periods and progressively extending them over time. Emphasizing nutrient-dense foods, including adequate protein, and staying hydrated are crucial aspects of the diet. Listening to one’s body and adjusting fasting periods based on individual comfort and tolerance is essential.
However, caution is advised, as improperly planned IER diets may lead to nutrient deficiencies. Consulting with a professional, especially for individuals with specific medical conditions, is recommended before embarking on an IER journey. Additionally, those with a history of disordered eating should avoid this style of eating.
In conclusion, this study underscores the potential benefits of IER not only in facilitating weight loss but also in positively influencing appetite regulation, willpower, and emotion. While IER may not suit everyone, it emerges as an effective tool for some individuals on their weight loss journey.