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Bad Influence

How the Internet Hijacked Our Health

Deborah Cohen author

Format:Hardback

Publisher:Oneworld Publications

Publishing:22nd Jan '26

£18.99

This title is due to be published on 22nd January, and will be despatched as soon as possible.

Bad Influence cover

When did we start trusting attractive influencers over qualified doctors?

When did we start trusting influencers over doctors?

You used to see a doctor. Now you go online.

'Your definitive guide to separating medical facts from online fiction.' Adam Kay, author of This is Going to Hurt

'This superb book is an essential guide to the wild world of internet health.' Chris van Tulleken, author of Ultra-Processed People

Need to focus? Want to lose weight? Build muscle? Get pregnant? Advice is just a click away.

With long waits for treatment and fewer face‑to‑face GP appointments, influencers have stepped into the breach. From doctors promoting untested therapies to celebrities selling solutions, these self-styled experts radiate wellness and guarantee results.

Exploring the transformation of a healthcare system driven by online trends, Dr Deborah Cohen reveals the truth behind Ozempic influencers, AI-powered diagnoses, ‘preventative’ screening and Instagram’s favourite wearable tech.

Bad Influence is about the commodification of health in an age of anxiety and why we can no longer distinguish medicine from marketing.

'In a world where online medical opinions are fast and often dodgy, this is the perfect antidote.' Prof. Kevin Fong

'This superb book is an essential guide to the wild world of internet health – a series of cautionary tales, brilliantly told, about the perils of health influencers and the messages they peddle.' —Chris van Tulleken, author of Ultra-Processed People


'Uncomfortable but essential reading. Your definitive guide to separating medical facts from online fiction.' —Adam Kay, author of This is Going to Hurt


'Exhaustively researched – documents the tensions between amazing modern medicine and twenty-first-century quackery. An important reminder of how technology's tentacles are reaching into every corner of our lives, and the challenge to work out what's real.' —Laura Kuenssberg


'In a world where online medical opinions are fast and often dodgy, this is the perfect antidote.' —Prof. Kevin Fong


'This book tackles one of the most important health issues of our time. It isbrilliant, thorough and vital. Empowering for anyone who has ever come across health information, stories, or advice online – which is pretty much all of us.' —Prof. Daniel M. Davis, author of Self Defence: A myth-busting guide to immune health


'This book is a much-needed prescription for the unregulated world of online health misinformation by an expert, who knows and understands what she is talking about. The influence we are all under now to buy products, tests and gadgets that often have no proven value for our health is terrifying for society and actually bad for our health. I'll be telling my patients to read this!' —Dr Ellie Cannon


'In a world ever more obsessed with popularity, Deborah Cohen is that rare thing – a truth seeker. Razor sharp, prodigiously researched and written with a balance that is the hallmark of true intellect, Bad Influence is essential reading for anyone needing to navigate the increasingly murky interface between medicine and the online world which – let’s face it – is all of us.' —Dr Gabriel Weston, author of Direct Red


'Bad Influence arrives at a moment when fascination with health, longevity and "optimised living" has never been greater... With a reporter’s eye and a scientist’s precision, Deborah dissects the interventionist claims of the wellness industry and exposes the shaky evidence underpinning it. Her diagnosis is uncomfortable but urgent: that those selling us control over our health may, in fact, be the ones making us sick. Bad Influence is a must-read for anyone who has ever turned to the internet in search of better health – and a timely warning about the seductive power of bad influencers.' —Natasha Loder, Health Editor, Economist


'Eye-opening and concerning. This book will hopefully influence how you access healthcare information and maybe think twice before you make (often complex) decisions about your body based solely on your social media feed.' —Prof. John Tregoning, author of Live Forever?


'A timely and eye-opening investigation into how social media is reshaping the way we think about health... Bad Influence takes readers inside a world where personal narratives and viral trends have more power than peer-reviewed research... Essential reading for anyone with a social media account – or anyone who cares about the future of evidence-based medicine in an age of influence.' —Rebecca Coombes, Head of Journalism, British Medical Journal

ISBN: 9780861549887

Dimensions: 216mm x 135mm x 33mm

Weight: unknown

384 pages