{"id":464440,"date":"2026-05-02T05:26:39","date_gmt":"2026-05-02T05:26:39","guid":{"rendered":"https:\/\/www.europesays.com\/ie\/464440\/"},"modified":"2026-05-02T05:26:39","modified_gmt":"2026-05-02T05:26:39","slug":"immune-cells-remember-obesity-long-after-weight-loss-study-finds-sciencealert","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ie\/464440\/","title":{"rendered":"Immune Cells &#8216;Remember&#8217; Obesity Long After Weight Loss, Study Finds : ScienceAlert"},"content":{"rendered":"<p>Defeating <a href=\"https:\/\/www.sciencealert.com\/scientists-identify-the-most-dangerous-time-in-life-to-gain-weight\" rel=\"nofollow noopener\" target=\"_blank\">obesity<\/a> is rarely easy. For many people, even successful weight loss is followed by a prolonged struggle to prevent the weight from <a href=\"https:\/\/www.sciencealert.com\/our-brains-evolved-powerful-mechanisms-to-protect-our-weight\" rel=\"nofollow noopener\" target=\"_blank\">coming back<\/a>.<\/p>\n<p>Obesity relapse is common, and research indicates it&#8217;s more than a matter of willpower. Fat cells retain a <a href=\"https:\/\/www.sciencealert.com\/fat-cells-seem-to-cling-to-the-memory-of-being-obese-study-finds\" rel=\"nofollow noopener\" target=\"_blank\">&#8216;memory&#8217; of obesity<\/a> long after weight loss, studies have found, potentially undermining efforts to avoid regaining weight.<\/p>\n<p>And it&#8217;s not just fat cells. As researchers report in a new decade-long study, certain immune cells can also carry a persistent memory of obesity.<\/p>\n<p>This record can preserve an elevated risk of obesity-related illness, the study suggests, up to 10 years after a person slims down.<\/p>\n<p>The mechanism for this is <a href=\"https:\/\/www.sciencealert.com\/cannabis-use-is-linked-to-epigenetic-changes-scientists-discovered\" rel=\"nofollow noopener\" target=\"_blank\">DNA methylation<\/a>, a normal biological process in which <a href=\"https:\/\/www.sciencealert.com\/epigenetic-changes\" rel=\"nofollow noopener\" target=\"_blank\">methyl groups<\/a> latch onto DNA molecules, altering gene activity without disrupting the DNA sequence.<\/p>\n<p>In people who have recently recovered from obesity, specific additions to the DNA in <a href=\"https:\/\/www.immunology.org\/public-information\/bitesized-immunology\/cells\/helper-and-cytotoxic-t-cells\" rel=\"nofollow noopener\" target=\"_blank\">helper T cells<\/a> seem to preserve the cellular memory of being obese, promoting a dysregulated, pro-inflammatory condition that can endure for years despite reductions in body weight.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2026\/05\/BrainScanMRIObesitybright-642x260.jpg\" alt=\"MRI of the human brain\" width=\"642\" height=\"260\" class=\"wp-image-99004 size-medium\"   loading=\"lazy\"\/>The researchers found immune cells can carry a persistent &#8216;memory&#8217; of obesity through the process of DNA methylation. (Highwaystarz-Photography\/iStock\/Getty Images Plus)<\/p>\n<p>To determine this, researchers analyzed immune cells from several groups of human subjects. These included samples from patients with obesity who either exercised four times a week for 10 weeks or received injections of <a href=\"https:\/\/www.sciencealert.com\/semaglutide-may-reverse-damage-caused-by-osteoarthritis-study-suggests\" rel=\"nofollow noopener\" target=\"_blank\">semaglutide<\/a> for weight loss, along with control groups.<\/p>\n<p>They additionally studied samples from people with <a href=\"https:\/\/rarediseases.info.nih.gov\/diseases\/5787\/alstrom-syndrome\" rel=\"nofollow noopener\" target=\"_blank\">Alstr\u00f6m syndrome<\/a>, a rare genetic disorder that tends to involve childhood obesity, and from healthy matched pairs as controls.<\/p>\n<p>The researchers also investigated the mechanics of obesity&#8217;s lasting influence on immune function by analyzing the immune cells of mice that were fed high-fat diets, as well as blood donations from human volunteers.<\/p>\n<p>&#8220;The findings suggest that short-term weight loss may not immediately reduce the risk of some disease conditions associated with obesity, including type 2  <a href=\"https:\/\/www.sciencealert.com\/diabetes\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73018\" data-postid=\"199613\" rel=\"nofollow noopener\" target=\"_self\">diabetes<\/a> and some cancers,&#8221; <a href=\"https:\/\/www.birmingham.ac.uk\/news\/2026\/obesity-leaves-a-lasting-memory-in-immune-cells\" rel=\"nofollow noopener\" target=\"_blank\">says<\/a> co-lead author Claudio Mauro, an immunologist at the University of Birmingham in the UK.<\/p>\n<p>&#8220;Instead, ongoing weight management following loss will see the &#8216;obesity memory&#8217; slowly fade,&#8221; Mauro <a href=\"https:\/\/www.birmingham.ac.uk\/news\/2026\/obesity-leaves-a-lasting-memory-in-immune-cells\" rel=\"nofollow noopener\" target=\"_blank\">says<\/a>.<\/p>\n<p>&#8220;This may take several years of sustained weight loss maintenance, likely five to 10 years, though this requires further study, to fully reverse the effects of obesity on T cells.&#8221;<\/p>\n<p>These discoveries shed light on the immune system&#8217;s record-keeping habits, says senior author and molecular epidemiologist Belinda Nedjai from Queen Mary University London.<\/p>\n<p>&#8220;Our findings show that obesity is associated with durable epigenetic modifications that influence immune cell behavior,&#8221; Nedjai <a href=\"https:\/\/www.birmingham.ac.uk\/news\/2026\/obesity-leaves-a-lasting-memory-in-immune-cells\" rel=\"nofollow noopener\" target=\"_blank\">says<\/a>.<\/p>\n<p>&#8220;This suggests that the immune system retains a molecular record of past metabolic exposures, which may have implications for long-term disease risk and recovery.&#8221;<\/p>\n<p><a href=\"https:\/\/www.sciencealert.com\/newsletter?utm_source=promo_generic_health\" rel=\"nofollow noopener\" target=\"_blank\"><img decoding=\"async\" src=\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2026\/04\/1775864981_782_Generic-Health-Promo-Final-642x273.jpg\" alt=\"Subscribe to ScienceAlert's free fact-checked newsletter\" width=\"642\" height=\"273\" class=\"alignnone wp-image-182810 size-medium\"   loading=\"lazy\"\/><\/a><\/p>\n<p>In people with obesity, helper T cells &#8216;memorize&#8217; obesity and promote weight regain, as previous <a href=\"https:\/\/doi.org\/10.1038\/cmi.2017.36\" rel=\"nofollow noopener\" target=\"_blank\">research<\/a> has shown. The mechanism for this has remained unclear, however.<\/p>\n<p>The new study identifies two key cell functions as pathways for obesity-related methylation to influence helper T cells: <a href=\"https:\/\/www.sciencealert.com\/scientists-may-have-found-the-key-cellular-process-behind-aging-in-animals\" rel=\"nofollow noopener\" target=\"_blank\">autophagy<\/a>, the natural removal and recycling of cellular waste, and immune <a href=\"https:\/\/www.sciencealert.com\/aging-can-spread-through-your-body-via-a-single-protein-study-finds\" rel=\"nofollow noopener\" target=\"_blank\">senescence<\/a>, or aging of cells in the immune system.<\/p>\n<p>DNA methylation from obesity seems to affect both functions, a crucial insight about the prevalence and underpinnings of relapse, says co-author and immunologist Andy Hogan from Maynooth University in Ireland.<\/p>\n<p><strong>Related: <a href=\"https:\/\/www.sciencealert.com\/just-5-days-of-junk-food-can-trigger-obesitys-hold-on-your-brain\" rel=\"nofollow noopener\" target=\"_blank\">Just 5 Days of Junk Food Can Trigger Obesity&#8217;s Hold on Your Brain<\/a><\/strong><\/p>\n<p>&#8220;We know obesity is a chronic progressive and relapsing disease, and our findings provide further understanding of exactly what are the molecular mechanisms potentially driving the risk of relapsing, and highlight the challenges facing people living with obesity to successfully manage their weight,&#8221; he <a href=\"https:\/\/www.birmingham.ac.uk\/news\/2026\/obesity-leaves-a-lasting-memory-in-immune-cells\" rel=\"nofollow noopener\" target=\"_blank\">says<\/a>.<\/p>\n<p>These findings could also help set the stage for targeted treatments that, along with other interventions, reverse the effects of obesity on T cells.<\/p>\n<p>&#8220;Our study suggests potential therapeutic opportunities to expedite this process, such as repurposing drugs like SGLT2 inhibitors, which have shown promise in reducing inflammation and promoting immune-mediated clearance of senescent cells in obesity,&#8221; Mauro <a href=\"https:\/\/www.birmingham.ac.uk\/news\/2026\/obesity-leaves-a-lasting-memory-in-immune-cells\" rel=\"nofollow noopener\" target=\"_blank\">says<\/a>.<\/p>\n<p>The study was published in <a href=\"https:\/\/doi.org\/10.1038\/s44319-026-00765-w\" rel=\"nofollow noopener\" target=\"_blank\">EMBO Reports<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Defeating obesity is rarely easy. For many people, even successful weight loss is followed by a prolonged struggle&hellip;\n","protected":false},"author":2,"featured_media":464441,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[78],"tags":[18,135,19,17,808],"class_list":{"0":"post-464440","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-health","8":"tag-eire","9":"tag-health","10":"tag-ie","11":"tag-ireland","12":"tag-msft-content"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/116503327126164493","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/464440","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=464440"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/464440\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/464441"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=464440"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=464440"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=464440"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}