{"id":8394,"date":"2025-12-08T01:04:41","date_gmt":"2025-12-08T01:04:41","guid":{"rendered":"https:\/\/readtrends.com\/en\/intermittent-fasting-brain-changes\/"},"modified":"2025-12-08T01:04:41","modified_gmt":"2025-12-08T01:04:41","slug":"intermittent-fasting-brain-changes","status":"publish","type":"post","link":"https:\/\/readtrends.com\/en\/intermittent-fasting-brain-changes\/","title":{"rendered":"A Fasting-Style Diet Seems to Result in Dynamic Changes to Human Brains &#8211; ScienceAlert"},"content":{"rendered":"<article>\n<p>Researchers in China report that an intermittent energy restriction (IER) program produced measurable weight loss and linked shifts in both gut bacteria and activity in appetite- and addiction-related brain regions over a 62-day trial. The study followed 25 volunteers classified as obese and found an average loss of 7.6 kilograms (16.8 pounds), equal to about 7.8% of body weight. Functional MRI scans and stool and blood analyses showed time-linked changes between the gut microbiome and neural activity in areas such as the left inferior frontal orbital gyrus. The investigators say these dynamic brain\u2013gut changes may suggest new biological targets for preventing and treating obesity, though mechanisms remain unresolved.<\/p>\n<h2>Key takeaways<\/h2>\n<ul>\n<li>Trial size and duration: 25 participants with obesity completed a 62-day intermittent energy restriction program monitored for metabolic, microbial and brain changes.<\/li>\n<li>Weight loss: Participants lost on average 7.6 kg (16.8 lb), representing a mean reduction of 7.8% of baseline body weight.<\/li>\n<li>Brain imaging: fMRI detected altered activity in appetite- and addiction-related regions, including the left inferior frontal orbital gyrus, during and after the diet.<\/li>\n<li>Microbiome shifts: Stool and blood analyses identified compositional changes; Coprococcus comes and Eubacterium hallii showed negative associations with activity in the left inferior frontal orbital gyrus.<\/li>\n<li>Coupled dynamics: The study reports that brain activity and gut-microbiome composition changed in a time-coupled manner across the 62 days.<\/li>\n<li>Publication and provenance: Results were published in Frontiers in Cellular and Infection Microbiology and summarized in ScienceAlert in December 2023.<\/li>\n<li>Scope limits: Small sample size and short follow-up mean findings are preliminary and not yet generalizable to broader populations.<\/li>\n<\/ul>\n<h2>Background<\/h2>\n<p>Global obesity affects more than a billion people and is linked to increased risks of cardiovascular disease, certain cancers and metabolic disorders. Public-health interest in dietary strategies that can produce sustainable weight loss has driven renewed attention to intermittent fasting and intermittent energy restriction (IER) approaches. IER typically alternates days of reduced calorie intake with days of normal eating; proponents argue it yields metabolic benefits beyond continuous calorie restriction. Previous animal and human research has suggested a bidirectional communication system between the gut microbiome and central nervous system\u2014the so-called brain\u2013gut axis\u2014that influences appetite, reward and metabolic control.<\/p>\n<p>Despite mounting interest, the precise biological pathways that link transient dietary patterns to sustained changes in appetite regulation remain poorly defined. Past studies have often focused on either the microbiome or neural responses alone, limiting the ability to assess coordinated dynamics. The Chinese research team set out to monitor both domains concurrently during an IER regimen to determine whether microbial shifts and brain activity changes co-evolve during weight loss. The trial aimed to identify signals that might indicate which gut microbes and brain regions are most relevant to successful weight reduction and maintenance.<\/p>\n<h2>Main event<\/h2>\n<p>Between baseline and day 62, the 25 volunteers adhered to a structured IER program under clinical supervision. Researchers collected serial fMRI scans, stool samples and blood markers at prespecified time points to build a longitudinal profile of physiological change. Average body-weight loss was 7.6 kg (16.8 lb), or roughly 7.8% of initial body mass\u2014an outcome consistent with an effective short-term dietary intervention.<\/p>\n<p>Functional MRI analyses revealed modulation of activity in regions implicated in reward processing and executive control, notably the inferior frontal orbital gyrus on the left. These areas contribute to impulse control and the evaluation of food-related cues, suggesting the diet affected neural circuits that govern food-seeking behavior. At the same time, sequencing and metabolic profiling detected changes in gut microbial composition and metabolites that correlated with shifts in regional brain activity.<\/p>\n<p>Specifically, the study reported negative associations between the relative abundance of Coprococcus comes and Eubacterium hallii and activity in the left inferior frontal orbital gyrus. In practical terms, higher levels of these bacteria corresponded to lower activity in that prefrontal region\u2014an observation the authors emphasize as evidence of linked brain\u2013microbiome dynamics during caloric restriction and weight loss. Investigators cautioned that correlation does not establish a directional cause-and-effect relationship.<\/p>\n<p>Authors and affiliated scientists highlighted the dynamic nature of the changes: microbial and neural measures did not shift in a simple linear fashion but showed time-dependent coupling that tracked the intervention period. The research team published these observations in Frontiers in Cellular and Infection Microbiology in December 2023 and framed the findings as a step toward identifying testable targets in the brain\u2013gut\u2013microbiome axis for obesity interventions.<\/p>\n<h2>Analysis &#038; implications<\/h2>\n<p>The study strengthens the hypothesis that dieting-induced weight loss engages a coordinated brain\u2013gut response rather than acting on one compartment alone. If certain microbes modulate activity in prefrontal and reward circuits, or vice versa, interventions could be designed to nudge that axis toward sustained appetite control. Clinically, this suggests combining dietary regimens with microbiome-directed therapies (prebiotics, probiotics, targeted metabolites) or neuromodulation might improve long-term outcomes.<\/p>\n<p>However, the small sample (n=25) raises questions about statistical power and population diversity; participants were all classified as obese and recruited in China, and the short 62-day window captures initial responses but not long-term maintenance. Larger, randomized trials with longer follow-up are required to confirm which microbial taxa or brain signatures predict durable weight loss. The observed negative association of Coprococcus comes and Eubacterium hallii with prefrontal activity is intriguing, but mechanistic work\u2014ideally in parallel animal and human studies\u2014must test causality.<\/p>\n<p>From a mechanistic standpoint, candidate pathways include microbial production of neuroactive compounds (short-chain fatty acids, neurotransmitter precursors) that enter circulation or signal via the vagus nerve. The investigators note that the microbiome can synthesize neurotransmitters and other bioactive molecules, while the brain shapes eating behavior that in turn alters nutrient exposure in the gut. Untangling directionality will be critical before translating these correlations into clinical treatments such as targeted probiotic strains or neuromodulatory therapies.<\/p>\n<p>Policy and public-health implications remain provisional. If future work validates specific brain\u2013microbiome markers as mediators of successful weight loss, screening tools could stratify individuals for personalized dietary protocols. Yet implementing such biomarkers in routine care will require reproducibility across populations, cost-effective assays, and evidence that changing a given microbial or neural signal improves outcomes beyond existing behavioral strategies.<\/p>\n<h2>Comparison &#038; data<\/h2>\n<figure>\n<table>\n<thead>\n<tr>\n<th>Measure<\/th>\n<th>Baseline (mean)<\/th>\n<th>After 62 days<\/th>\n<th>Change<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Body weight<\/td>\n<td>\u2014<\/td>\n<td>Mean \u22127.6 kg (\u221216.8 lb)<\/td>\n<td>\u22127.8% of baseline<\/td>\n<\/tr>\n<tr>\n<td>Participants<\/td>\n<td>25 enrolled<\/td>\n<td>25 completed<\/td>\n<td>0 dropouts reported<\/td>\n<\/tr>\n<tr>\n<td>Key brain region<\/td>\n<td>Left inferior frontal orbital gyrus activity<\/td>\n<td>Altered activity vs baseline<\/td>\n<td>Time-coupled change with microbiome<\/td>\n<\/tr>\n<tr>\n<td>Noted microbes<\/td>\n<td>Coprococcus comes, Eubacterium hallii (baseline levels)<\/td>\n<td>Relative abundance changed over time<\/td>\n<td>Negative association with prefrontal activity<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<p>The table summarizes principal quantitative findings reported by the research team: clinically meaningful weight loss accompanied by linked shifts in brain activity and microbiome composition. Readers should note the study reports associations and percent changes rather than causal interventions targeted at specific microbes or brain areas. Comparisons to larger, longer trials are not yet available.<\/p>\n<h2>Reactions &#038; quotes<\/h2>\n<p>Outside and inside the author group, experts emphasized the novelty of simultaneously tracking neural and microbial responses during a controlled diet, while urging caution about overinterpretation.<\/p>\n<blockquote>\n<p>&#8220;Here we show that an IER diet changes the human brain\u2013gut\u2013microbiome axis,&#8221;<\/p>\n<p><cite>Qiang Zeng, Second Medical Center and National Clinical Research Center for Geriatric Diseases (study author)<\/cite><\/p><\/blockquote>\n<p>Zeng framed the work as evidence of coordinated change across systems rather than proof of a single causal pathway. He and colleagues present the data as a foundation for targeted studies to test whether altering the microbiome or neural activity can improve weight-loss maintenance.<\/p>\n<blockquote>\n<p>&#8220;The microbiome produces neurotransmitters and neurotoxins which access the brain through nerves and the blood circulation,&#8221;<\/p>\n<p><cite>Xiaoning Wang, State Clinic Center for Geriatrics (medical scientist)<\/cite><\/p><\/blockquote>\n<p>Wang emphasized known biological routes of gut\u2013brain communication, noting that diet-driven nutrient changes can reshape microbial communities and thereby influence signaling to the central nervous system. She framed the findings as consistent with established two-way communication models.<\/p>\n<blockquote>\n<p>&#8220;The next question is the precise mechanism by which the gut microbiome and the brain communicate in obese people, including during weight loss,&#8221;<\/p>\n<p><cite>Liming Wang, Chinese Academy of Sciences (biomedical scientist)<\/cite><\/p><\/blockquote>\n<p>Liming Wang highlighted the need to identify which specific microbes and brain regions are most relevant to sustained weight reduction and to test their causal roles in follow-up studies.<\/p>\n<aside>\n<details>\n<summary>Explainer: brain\u2013gut\u2013microbiome axis<\/summary>\n<p>The brain\u2013gut\u2013microbiome axis describes bidirectional signaling between the gastrointestinal tract, its resident microbes and the central nervous system. Signals include microbial metabolites (short-chain fatty acids), microbial synthesis of neurotransmitter precursors, immune mediators and neural pathways such as the vagus nerve. Diet rapidly alters nutrient availability in the gut, which can shift microbial composition within days. Changes in microbial products can influence gut barrier function, systemic inflammation and neural circuits that regulate appetite, mood and reward-seeking. Because signals operate in both directions, distinguishing whether the microbiome drives neural change or responds to altered eating behavior requires controlled, mechanistic experiments.<\/p>\n<\/details>\n<\/aside>\n<h2>Unconfirmed<\/h2>\n<ul>\n<li>Whether microbial changes drive the observed brain-activity shifts, or whether neural changes alter the microbiome, remains unproven and requires causal testing.<\/li>\n<li>Long-term durability: It is not established that the measured changes persist past the 62-day study window or predict sustained weight maintenance.<\/li>\n<li>Generalisability to other populations (different ethnicities, ages, metabolic profiles) has not been demonstrated given the small, regionally limited sample.<\/li>\n<li>Specific mechanisms by which Coprococcus comes and Eubacterium hallii might influence prefrontal activity are hypothesized but not experimentally verified.<\/li>\n<\/ul>\n<h2>Bottom line<\/h2>\n<p>This controlled 62-day IER trial in 25 volunteers with obesity shows that meaningful short-term weight loss can coincide with coordinated changes in gut-microbiome composition and activity in appetite- and addiction-related brain regions. The coupling of microbial and neural measures is a notable advance because it opens concrete hypotheses about which biological signals might be manipulated to aid weight control. Yet these results are preliminary: small sample size, limited follow-up and correlational design mean clinical translation is not immediate.<\/p>\n<p>Next steps should prioritize larger randomized trials with mechanistic substudies\u2014measuring metabolites, neural causality (for example, via neuromodulation or animal models) and longer-term follow-up on weight maintenance. If reproducible, identifying specific microbial taxa or brain signatures that predict successful, durable weight loss could inform personalized obesity treatments combining dietary, microbial and neural approaches.<\/p>\n<h2>Sources<\/h2>\n<ul>\n<li><a href=\"https:\/\/www.sciencealert.com\/a-fasting-style-diet-seems-to-result-in-dynamic-changes-to-human-brains\" target=\"_blank\" rel=\"noopener\">ScienceAlert \u2014 news report summarizing the study (journalism)<\/a><\/li>\n<li><a href=\"https:\/\/www.frontiersin.org\/journals\/cellular-and-infection-microbiology\" target=\"_blank\" rel=\"noopener\">Frontiers in Cellular and Infection Microbiology \u2014 journal (peer-reviewed)<\/a><\/li>\n<li><a href=\"https:\/\/www.who.int\/news-room\/fact-sheets\/detail\/obesity-and-overweight\" target=\"_blank\" rel=\"noopener\">World Health Organization \u2014 obesity and overweight fact sheet (official public health)<\/a><\/li>\n<\/ul>\n<\/article>\n","protected":false},"excerpt":{"rendered":"<p>Researchers in China report that an intermittent energy restriction (IER) program produced measurable weight loss and linked shifts in both gut bacteria and activity in appetite- and addiction-related brain regions over a 62-day trial. The study followed 25 volunteers classified as obese and found an average loss of 7.6 kilograms (16.8 pounds), equal to about &#8230; <a title=\"A Fasting-Style Diet Seems to Result in Dynamic Changes to Human Brains &#8211; ScienceAlert\" class=\"read-more\" href=\"https:\/\/readtrends.com\/en\/intermittent-fasting-brain-changes\/\" aria-label=\"Read more about A Fasting-Style Diet Seems to Result in Dynamic Changes to Human Brains &#8211; ScienceAlert\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":8392,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"rank_math_title":"Fasting-style diet alters brain\u2013gut axis and weight \u2014 DeepScience","rank_math_description":"A 62-day intermittent energy restriction trial in 25 people found 7.6 kg average weight loss and linked gut microbiome shifts to changes in appetite-related brain activity.","rank_math_focus_keyword":"intermittent fasting,brain-gut axis,microbiome,obesity,weight loss","footnotes":""},"categories":[2],"tags":[],"class_list":["post-8394","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-top-stories"],"_links":{"self":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/posts\/8394","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/comments?post=8394"}],"version-history":[{"count":0,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/posts\/8394\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/media\/8392"}],"wp:attachment":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/media?parent=8394"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/categories?post=8394"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/tags?post=8394"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}