{"id":219711,"date":"2026-01-06T13:51:08","date_gmt":"2026-01-06T13:51:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/219711\/"},"modified":"2026-01-06T13:51:08","modified_gmt":"2026-01-06T13:51:08","slug":"study-raises-serious-questions-about-the-benefits-of-intermittent-fasting-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/219711\/","title":{"rendered":"Study Raises Serious Questions About The Benefits of Intermittent Fasting : ScienceAlert"},"content":{"rendered":"<p>The notion behind <a href=\"https:\/\/www.sciencealert.com\/intermittent-fasting-does-work-for-weight-loss-but-only-if-you-follow-this-rule\" rel=\"nofollow noopener\" target=\"_blank\">intermittent fasting<\/a> is simple: eat less for a time, improve your metabolism. The reality is more complex, and a new study finds that some forms of intermittent fasting do not alter markers of metabolic or cardiovascular health.<\/p>\n<p>Researchers, led by a team from the German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), put 31 women <a href=\"https:\/\/www.sciencealert.com\/fat-cells-seem-to-cling-to-the-memory-of-being-obese-study-finds\" rel=\"nofollow noopener\" target=\"_blank\">who were overweight<\/a> or obese on two different intermittent fasting schedules for two weeks each. The schedules were 8 am to 4 pm or 1 pm to 9 pm, a particular kind of intermittent fasting known as time-restricted eating (TRE).<\/p>\n<p>While the timing of the schedules differed, the diet parameters were the same: participants could eat <a href=\"https:\/\/www.sciencealert.com\/high-fat-diets-may-break-the-brains-ability-to-regulate-calories\" rel=\"nofollow noopener\" target=\"_blank\">like they normally did<\/a>, and therefore take in the same amount of total calories (making this what&#8217;s known as an isocaloric study).<\/p>\n<p>Related: <a href=\"https:\/\/www.sciencealert.com\/a-fasting-style-diet-seems-to-result-in-dynamic-changes-to-human-brains\" rel=\"nofollow noopener\" target=\"_blank\">A Fasting-Style Diet Seems to Result in Dynamic Changes to Human Brains<\/a><\/p>\n<p>Although the women lost some weight, other benefits that might be expected based on <a href=\"https:\/\/doi.org\/10.1016\/j.cmet.2018.04.010\" rel=\"nofollow noopener\" target=\"_blank\">previous research<\/a> \u2013 including lower blood sugar levels, lower blood pressure, and <a href=\"https:\/\/www.sciencealert.com\/experts-reveal-how-to-actually-lower-your-cholesterol\" rel=\"nofollow noopener\" target=\"_blank\">lower cholesterol<\/a> \u2013 didn&#8217;t show up in the data, raising questions about just how effective these timed fasting routines are.<\/p>\n<p>&#8220;The beneficial cardiometabolic effects described previously might be induced by TRE-mediated calorie restriction and not by the shortening of the eating window itself,&#8221; <a href=\"https:\/\/doi.org\/10.1126\/scitranslmed.adv6787\" rel=\"nofollow noopener\" target=\"_blank\">write<\/a> the researchers in their published paper.<\/p>\n<p>&#8220;In this nearly isocaloric trial, no improvements in metabolic parameters were observed after two weeks of TRE.&#8221;<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/nz\/wp-content\/uploads\/2026\/01\/GlucoseProfile.jpg\" alt=\"Glucose level chart\" width=\"642\" height=\"420\" class=\"wp-image-187651 size-full\"   loading=\"lazy\"\/>The researchers looked at health indicators like glucose levels. (Peters et al., Sci. Transl. Med., 2025)<\/p>\n<p>The findings suggest it may be <a href=\"https:\/\/www.sciencealert.com\/weight-loss-involves-more-than-calories-in-calories-out-heres-how\" rel=\"nofollow noopener\" target=\"_blank\">calorie reduction<\/a> rather than time-restricted eating itself that boosts key indicators of health inside the body, although it&#8217;s important to bear in mind this was a relatively small-scale, short-term study.<\/p>\n<p>In addition to the study&#8217;s modest reductions in body weight, researchers observed changes in participants&#8217; body clocks. The timing of their <a href=\"https:\/\/www.sciencealert.com\/scientists-explain-why-you-wake-up-minutes-before-your-alarm\" rel=\"nofollow noopener\" target=\"_blank\">circadian rhythms<\/a>, including those that nudge the body towards sleep, was shifted based on the TRE schedule.<\/p>\n<p>It&#8217;s more evidence that our internal clocks can be partially controlled by when we drink and eat, as well as through other triggers (such as when <a href=\"https:\/\/www.sciencealert.com\/stunning-sunset-images-on-the-moon-could-help-solve-enduring-mystery\" rel=\"nofollow noopener\" target=\"_blank\">the Sun goes down<\/a>). This could play into health problems associated with eating late at night, for example.<\/p>\n<p>&#8220;Those who want to lose weight or improve their metabolism should pay attention not only to the clock, but also to their energy balance,&#8221; <a href=\"https:\/\/www.dzd-ev.de\/en\/article\/intervallfasten-ohne-kalorienreduktion-verbessert-nicht-die-stoffwechselgesundheit-verschiebt-aber-die-innere-uhr\" rel=\"nofollow noopener\" target=\"_blank\">says<\/a> biologist and nutritionist Olga Ramich, from the DIfE.<\/p>\n<p>Improving metabolic health is particularly important when tackling insulin resistance and  <a href=\"https:\/\/www.sciencealert.com\/diabetes\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73018\" data-postid=\"187648\" rel=\"nofollow noopener\" target=\"_self\">diabetes<\/a>. Future findings like these may change how diets are structured for people with conditions like these or who are <a href=\"https:\/\/www.sciencealert.com\/caffeine-in-your-blood-could-affect-body-fat-and-diabetes-risk-study-reveals\" rel=\"nofollow noopener\" target=\"_blank\">at risk of developing<\/a> them.<\/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.newsbeep.com\/nz\/wp-content\/uploads\/2026\/01\/1767449653_841_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>The researchers are keen to continue investigating the relationship between calorie consumption and calorie timing. It&#8217;s possible that in hypocaloric scenarios (when calories are restricted), timing may have some influence on biological markers of health.<\/p>\n<p>Various types of intermittent fasting continue to be analyzed by researchers, but studies <a href=\"https:\/\/www.sciencealert.com\/study-reveals-intermittent-fasting-has-2-key-benefits-for-people-with-obesity\" rel=\"nofollow noopener\" target=\"_blank\">can differ substantially<\/a> in terms of the diets that are allowed, the participants, study duration, and the health benefits measured.<\/p>\n<p>&#8220;Our findings suggest the importance of calorie restriction for metabolic improvements in TRE,&#8221; <a href=\"https:\/\/doi.org\/10.1126\/scitranslmed.adv6787\" rel=\"nofollow noopener\" target=\"_blank\">write<\/a> the researchers.<\/p>\n<p>&#8220;Whether the timing of eating under the hypocaloric conditions can additionally contribute to metabolic changes and whether the optimal eating timing differs between individuals warrants investigation in future studies.&#8221;<\/p>\n<p>The research has been published in <a href=\"https:\/\/doi.org\/10.1126\/scitranslmed.adv6787\" rel=\"nofollow noopener\" target=\"_blank\">Science Translational Medicine<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"The notion behind intermittent fasting is simple: eat less for a time, improve your metabolism. The reality is&hellip;\n","protected":false},"author":2,"featured_media":219712,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[36],"tags":[134,1021,111,139,556,69],"class_list":{"0":"post-219711","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-nutrition","8":"tag-health","9":"tag-msft-content","10":"tag-new-zealand","11":"tag-newzealand","12":"tag-nutrition","13":"tag-nz"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/219711","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=219711"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/219711\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/219712"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=219711"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=219711"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=219711"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}