Discover the truth about our immune system and learn how to stay healthy – from the world-leading scientist our health experts turn to.

‘Astounding. Will change how you think about your body and live your life’ – CHRIS VAN TULLEKEN, author of Ultra-Processed People

‘Incredibly impressive … Brilliant’ – LIZ EARLE, author of How to Age

‘A great book from a world expert’ – TIM SPECTOR, author of Food for Life and co-founder of ZOE

Is it true that orange juice wards off colds? Are mental health and inflammation really connected How do we distinguish bogus claims from useful advice – and what can we actually do to support our immune system and stay healthy?

Globally renowned immunologist Daniel M. Davis cuts through the noise to reveal the truth about our immune system – from the effects of diet, exercise and the microbiome to stress, sleep and old age. In an era of misinformation and marketing slogans, this ground-breaking guide equips us all with the key insights we urgently need to make wiser decisions for our health.

‘Illuminating ... fascinating’ – DAILY MAIL ** BEST BOOKS OF THE YEAR 2025 **

‘Bridges the gap between scientific research ... and what people want to know about immunity’ – TIMES LITERARY SUPPLEMENT

‘Exceptional’ – SCIENCE

*Published in hardback as Self Defence: A Myth-busting Guide to Immune Health

"As renowned immunologist Davis argues, the immune system is extremely complicated and widely misunderstood … Offers an illuminating picture of a fascinating area of science" - Daily Mail, Best Health Books of 2025

"Bridge[s] the gap between the scientific research of [Davis'] day job and what people want to know about immunity .. The immune system can be hard to unravel ... Daniel M. Davis follows the twists and turns of the evidence and offers nuanced responses to immune health questions ... Above all, his friendly tone and clear writing give the reader a much deeper appreciation of the complexity of the human body" - Times Literary Supplement

"Top immunologist Daniel M. Davis separates fact from fiction in this insightful guide" - Woman's Weekly

"Treads familiar questions with exceptional sharpness … The book succeeds in inoculating the reader against easy health answers, headlines, and platitudes" - Science

"Eradicate[s] long-held myths and replace[s] them with wonder at the complexity of the body’s defence system" - New Scientist

"Davis’ work shines a light on how immunology can influence our health, demystify the science behind many diet and lifestyle claims, and helps his audiences understand just how complex our biological systems really are" - British Society for Immunology

"For each topic, Davis presents a story of twisting lanes driving readers towards actionable ways to optimise health" - Commentary