The last few years have seen a proliferation of popular science books in the mental health and neuroscience fields. Some of these are excellent but, sadly, many are low on evidence and big on hype and self-promotion. Phillip Gold's book on the causes and treatment of depression is a very welcome change. It is written by an expert clinician scientist who has dedicated his entire professional life – 50 years and counting – to researching and treating depressive disorders. Gold has made an enormous contribution to psychiatry and has an infectious optimism about how current and imminent discoveries will soon be translated into better treatments for patients.

There are many excellent aspects to this book. The most striking is the way in which complex science is communicated in simple and compelling language. In the early chapters, Gold suggests that depression should be considered ‘an adaptive stress response gone awry’ and explains how an otherwise normal stress response can, in some people, ‘morph into a pernicious state of anguish and despair’. He reminds us that we have evolved to react to threat situations with a narrowing of our attention, with increased heart rate and blood pressure, increased blood glucose, and with increased inflammation and blood clotting (in preparation for injury). For most of us, these responses resolve as the threat dissipates but for individuals made vulnerable by their genetics and previous experiences, this can become a sustained response that results in depression. This sustained stress response also explains the long-term physical sequelae of depression, such as obesity, diabetes, osteoporosis, cardiovascular disease, stroke and premature mortality. It also explains why depression should be considered a whole-body disorder.

Throughout the book Gold discusses the presentation and pathophysiology of two main subtypes of depression: melancholic depression and atypical depression. He suggests that melancholic depression is an exaggerated expression of a healthy stress response whereas atypical depression represents a stress system ‘locked in the off position'. The evidence presented in support of this (much of it based on Gold's own research) is compelling and has important implications for the way in which we assess and treat patients with depressive disorders.

Another strength of this book is the way that case histories of patients that Gold himself has treated are used to illustrate the relevance of the science he discusses. These histories are highly engaging and described with empathy and compassion. Gold trained in psychoanalytic psychotherapy before his research career began and throughout the book he emphasises the importance of combining biological treatments with long-term psychotherapeutic insights and approaches.

Many of the chapters cover familiar ground – including antidepressants, genetics, lithium and ECT – but each chapter provides novel insights. Gold's long and distinguished career at the US National Institute of Mental Health (NIMH) gives him a unique perspective on how these areas of discovery science began (often serendipitously) and then subsequently evolved. I particularly enjoyed the chapters on circadian rhythms and hormones, both of which communicate the excitement of scientific discovery and how this leads on to new thinking about how we should diagnose, classify and treat depressive disorders. It also clear from these chapters that NIMH was (and remains) a unique place in which to conduct world-leading mental health research.

There are also two very important chapters on psychedelics and ketamine, which provide state-of-the-art summaries. These treatments clearly have pros and cons but, on balance, they are likely to become available to more and more patients with severe depression within the near future. As psychiatrists, we all need to understand the science behind these treatments and this book is a great place to start.

I have two minor criticisms of this book. Firstly, it is sometimes overly US-centric and neglects to credit the achievements of researchers working in other areas of the world over the last 50 years. Science is a global endeavour and open science practices (including collaboration, data sharing, transparency in methods, and commitments to equality and diversity) have always been critical for success. Secondly, I was a little uncomfortable with the way in which the value of the contribution of named colleagues and researchers in this book was (at least in part) measured in terms of where they studied (usually Yale or Harvard), how famous their mentors were, how many publications they had (apparently Eric Nestler has 650!), and whether or not they had been awarded a Lasker or Nobel prize. Perhaps I am being unfair, but these metrics are not really how we should be measuring success, especially when science is such a collaborative effort.

Overall, I am extremely enthusiastic about this book. It is short, readable, and full of compassion and important insights. I wish this book had been available when I was a trainee in psychiatry and I'm sure it will be enjoyed by many psychiatrists, patients and their families. I am grateful that Phillip Gold has found the time to write this excellent summary of his life's work and I commend it to anyone with an interest in the science and treatment of depression.