Jenna Macciochi - Staying Well: How to Build a Healthy Immune System in the Modern World

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First published by Thorsons 2020

FIRST EDITION

Dr Jenna Macciochi 2020

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A catalogue record of this book is available from the British Library

Dr Jenna Macciochi asserts the moral right to be identified as the author of this work

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Source ISBN: 9780008370268

Ebook Edition: March 2020 ISBN: 9780008370275

Version: 2020-03-12

To Luca and Isabella who have given me so

much in such a short time.

And to all those who believed in me when

I struggled to believe in myself.

In this book I have sought to present some of the current and big ideas in my field, fusing them with my own stories, personal anecdotes and my passion for this subject. My aim was also to convey a sense of wonderment for this silent system and the vast and complex science it encompasses. I am acutely aware that this is not and could never be an exhaustive text on the immune system. In my attempt to keep the narrative and scientific ideas as clear as possible for the general reader, I could not cover all the topics I wanted to or discuss them in the depth they may warrant. And rather than present a complete textbook-level description, I have deliberately chosen to focus on the broader contemporary issues to bring an awareness to how modern lifestyles and our rapidly changing environment interact with and shape our immunity and, ergo, our health. In my quest to be evidence-based I have dived into the scientific literature, consulted with colleagues and reached out to other experts along the way, combining this information with case studies and alternative health literature to give a balanced and holistic overview. In some cases the only evidence available is weak or at least not the most rigorous, so I have made efforts to state this where appropriate. Ultimately, any one book can only tell part of a story and this, I hope, is just part one.

There is no permanent ideal of disease resistance, merely the shifting sands of impermanent obsolescence.

MATT RIDLEY , author

Described by the US National Library of Medicine as the most complex system that the body has, our immune system is a vast constellation of cells and molecules spanning every nook and cranny of our bodies.

WHATS IMMUNITY AND WHY SHOULD YOU CARE?

Immunity, from the Latin immunis meaning exempt, refers to the art and science of the human immune system the various biological defence systems that keep us well. The immune system is a silent wonder. While we are very aware of our hearts beating and the breaths we take, we are much less aware of our immune system and the many jobs it performs to keep us well. This mighty system protects our health by resisting uninvited infections, maintaining order and balance in our bodies, and healing wounds. It is our foundation to wellbeing.

Immunology, the extraordinarily rich, yet complex study of the immune system, has changed the face of modern medicine over the last 30 years. There has never been a more fascinating time to delve into immunology and harness its power to improve your health. And that is what this book will do for you. Based on cutting-edge, evidence-based scientific research, this book takes you on an empowering journey through the latest astonishing discoveries in immunology. You will get to know the immune system inside out and come to an intimate understanding of how it works.

It is not often that one body system touches so many aspects of human biology in both sickness and health. Although it is seemingly esoteric and beyond comprehension at first blush, the immune system is the epitome of versatility and simplicity of purpose.

When it comes to maintaining good health, the immune system is our most precious asset, yet we rarely appreciate our essential defences until something goes wrong. We thank our immune system when we catch a cold and scramble for vitamin C supplements in the winter months. But what about all the other wonders it works? If it only existed for the first few weeks of chilly weather every year, wed all be in serious trouble. Most of the time our immune system is working away in the background and we dont even notice it. Deeply entwined with every aspect of our physical and mental health, it lays the foundations of our health and longevity.

Immunity is a sophisticated system, with astonishing complexity. But there is a lot that can go wrong, from autoimmune diseases and allergies, to mental-health problems and metabolic issues even cancer. We have an obsession with looking healthy and being well, and yet we are sicker and unhappier than ever before. Thats because our delicately balanced immunity is easily compromised by our ever-accelerating pace of life, with its relentless stress, pollution, overconsuming and under-moving. What modern life deems healthy may not actually be so. Today, were more likely to die from a lifestyle-related disease than any other cause, and many of these would be preventable if we took better care of our health.

On our journey through modern immunology, youll discover why the immune system is your sixth sense, connecting your health to your environment, feelings and emotions; why some people rarely get sick; what to do if you have a chronic illness; and what it really means to boost your immunity.

My endless wonder at this vast and elegant system, integral to our wellbeing, has been the driving force behind both my career and personal life. From an early age I was intrigued by the human body, health and disease. My mum, a trained cook, strongly believed that health was in our own hands and taught me the old-fashioned cookery basics that have become a vital tool in my modern-day mumlife toolbox. She was the original purveyor of old wives tales. Yet there was a wealth of untapped wisdom in her words that left me with a lingering curiosity, shaping my path as I embarked on my scientific career.

As Ive discovered more about the immune system, Ive found myself changing how I live in response to what Ive learned. Im driven to question what modern life tells us is healthy, yet makes our immunity go awry. Every day I find myself hunting for clues, researching the evolution of the immune system and thinking about the traditional ways of life that have shaped our health. Have we thrown the baby out with the bathwater by swapping old ways for new and shiny modern ones? This is a question I keep coming back to, and one which Ill answer in the chapters that follow, while also exploring how we can reclaim our innate knowledge of immunity through traditional rituals, supported by science. Keep in mind as you move through the chapters that the immune system is a bit like a wiggly moving octopus. Its undulating nature makes it difficult to cover it in a linear, page-by-page fashion. And one of its slippery charms is that the answer to many questions about it begin with It depends or Its complicated. Understanding the secrets of how to be well requires a balance between openness to new ideas (no matter how counterintuitive they may seem) and ruthless scrutiny of all concepts both old and new.