--- title: Chronic-Fatigue Syndrome Reamed Systemic-Exertion-Intolerance Disease description: Chronic-fatigue syndrome has been renamed systemic-exertion-intolerance disease (SEID) and proclaimed real by the Institute of Medicine canonical: https://time.com/3706453/chronic-fatigue-syndrome-systemic-exertion-intolerance-disease/ author: Sabrina Toppa article:opinion: false article:content_tier: free article:published_time: 2015-02-12T08:30:56.000Z article:modified_time: 2026-03-31T08:11:28.878Z article:section: Health og:title: Chronic-Fatigue Syndrome Proclaimed Real and Renamed og:description: It's now called systemic-exertion-intolerance disease (SEID), and your doctor is wrong about it not being genuine og:url: https://time.com/3706453/chronic-fatigue-syndrome-systemic-exertion-intolerance-disease/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt4401ad42a2168fe2/69877eeb2dce0132a39dd851/482136845.jpg?branch=production&width=1200&quality=75&auto=webp&crop=16:9 og:image:width: 5119 og:image:height: 2879 og:image:alt: 482136845 og:type: article twitter:card: summary_large_image twitter:title: Chronic-Fatigue Syndrome Proclaimed Real and Renamed twitter:description: It's now called systemic-exertion-intolerance disease (SEID), and your doctor is wrong about it not being genuine twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt4401ad42a2168fe2/69877eeb2dce0132a39dd851/482136845.jpg?branch=production&width=1200&quality=75&auto=webp&crop=16:9 ---  # Chronic-Fatigue Syndrome Is Real and Is Now Called Systemic-Exertion-Intolerance Disease > Sponsored content. 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Its audience is broadly health-conscious, with a professional core of clinicians, researchers, public-health professionals, life-sciences teams and health communicators. by [Sabrina Toppa](https://time.com/author/sabrina-toppa/) ## Sabrina Toppa Feb 12, 2015 8:30 AM UTC  Hispanic teenage girl covering eyes in bed Hispanic teenage girl covering eyes in bed Getty Images by [Sabrina Toppa](https://time.com/author/sabrina-toppa/) ## Sabrina Toppa Feb 12, 2015 8:30 AM UTC Sufferers of chronic-fatigue syndrome have long complained about what they regard as a trivializing name for their condition. Now, they can claim two victories: it was [renamed](http://www.npr.org/blogs/health/2015/02/11/385465667/panel-says-chronic-fatigue-syndrome-is-a-disease-and-renames-it) systemic-exertion-intolerance disease (SEID), and was proclaimed to be a real disease by a panel from the Institute of Medicine, an influential government advisory body. The 15-member panel, which released a 235-page report Tuesday also offered new and simplified diagnostic criteria: profound fatigue, total exhaustion after even minor physical or mental exertion, unrefreshing sleep and “brain fog.” The disease, afflicting anywhere from 860,000 to 2.5 million Americans, can leave sufferers incapacitated, incapable of attending school or going to work. The majority are undiagnosed because there is no test and sufferers battle a prevailing stigma that their ailment is primarily psychological. \[[_NPR_](http://www.npr.org/blogs/health/2015/02/11/385465667/panel-says-chronic-fatigue-syndrome-is-a-disease-and-renames-it)\] ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/3706453/chronic-fatigue-syndrome-systemic-exertion-intolerance-disease/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/3706453/chronic-fatigue-syndrome-systemic-exertion-intolerance-disease/"},"headline":"Chronic-Fatigue Syndrome Is Real and Is Now Called Systemic-Exertion-Intolerance Disease","datePublished":"2015-02-12T08:30:56.000Z","dateModified":"2026-03-31T08:11:28.878Z","description":"Top medical advisory body publishes comprehensive report","url":"https://time.com/3706453/chronic-fatigue-syndrome-systemic-exertion-intolerance-disease/","keywords":["Research","health","Report","diseases"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt4401ad42a2168fe2/69877eeb2dce0132a39dd851/482136845.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Sabrina Toppa","jobTitle":"","url":"https://time.com/author/sabrina-toppa/"}],"articleSection":"Health","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt4401ad42a2168fe2/69877eeb2dce0132a39dd851/482136845.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"482136845","caption":"482136845","creditText":"Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/health/","name":"Health"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/research/","name":"Research"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/3706453/chronic-fatigue-syndrome-systemic-exertion-intolerance-disease/","name":"Chronic-Fatigue Syndrome Is Real and Is Now Called Systemic-Exertion-Intolerance Disease"}}]}] ```