Book SummaryThe Cancer Code, by Jason Fung

1-Page Summary1-Page Book Summary of The Cancer Code

Cancer is one of the most frightening diseases in the world today; it’s deadly and often extremely hard to cure. As such, doctors and researchers have spent enormous amounts of time and money trying to figure out exactly what cancer is, how it works, and how to cure it. The Cancer Code by Jason Fung is an overview of scientists’ major discoveries about cancer, starting from ancient times and continuing to the present day. Published in 2020, it’s one of the most up-to-date and comprehensive books on this topic.

Fung breaks down the history of cancer research into three paradigms, which this guide will refer to as Models for simplicity's sake. These Models are different ways scientists of the time understood cancer: why it occurred, how it progressed, and how it could be...

The Cancer Code Summary Model 1: Cancer as Uncontrolled Growth

In order to treat cancer, scientists first had to answer the question: What is cancer? In other words, they needed to figure out what was going wrong with patients’ bodies so that they could determine how to fix the problems.

Fung says that scientists’ earliest understanding of cancer—dating at least back to Ancient Egypt—was simply a description of its symptoms, most notably the tumors that form in patients’ bodies. As such, many scientists developed an understanding of cancer as an abnormal growth that would eventually kill its victim. Others believed that cancer was caused by an imbalance of black “bile” in the body.

(Shortform note: Both this book and Siddhartha Mukherjee’s The Emperor of All Maladies discuss the Ancient Greek belief, dating to around 130 AD, that cancer was caused by an imbalance of black bile (which we now know doesn’t exist). However, Mukherjee adds that the theory—though wrong—was extraordinary for its time because it recognized that cancer was a systemic problem rather than a localized growth....

The Cancer Code Summary Model 2: Cancer as the Result of Genetic Mutations

Early doctors’ concept of cancer as simply a harmful tumor wasn’t enough for them to truly understand or treat it. Fung tells us that it took until the 1900s—when scientists began exploring the field of genetics in earnest—to develop a more accurate model of cancer.

This new model, which we’re calling Model 2, described cancer not merely as a growth but also as the result of harmful mutations in a cell’s DNA. Those mutations caused normal processes, such as energy production and cell division, to run wild.

In short, Model 1 described cancer’s symptoms, while Model 2 described its mechanisms: the biological processes behind the disease. By learning how malignant cells functioned, scientists believed that they would be able to develop treatments that disrupted those functions, thereby curing the disease.

What Are Mutations?

In simple terms, a mutation is a change to a cell’s DNA (its genetic information). DNA carries instructions for building various proteins; those proteins go on to perform countless different functions, including...

The Cancer Code Summary Model 3: Cancer as an Evolving Species

Having dismissed both of the previous models, Fung presents a newer hypothesis. Model 3 was not proposed by a biologist, but by physicist Paul Davies, whom the National Cancer Institute reached out to in 2009 in the hope that an outsider’s viewpoint could provide some new insights about cancer.

Model 3 suggests that cancer is an atavism: an evolutionary throwback in which ancestral traits reemerge in modern organisms. In this case, Davies proposed that cancer is the re-emergence of traits from the earliest single-celled organisms, caused by evolutionary pressure from carcinogens. (We’ll explain this evolutionary pressure in more detail later.)

In short, Model 1 described what cancer is, Model 2 described how it works, and now Model 3 offers a theory about why it happens.

(Shortform note: In The Selfish Gene, biologist Richard Dawkins gives an idea of what these earliest organisms might have been like. He describes simple molecules that gained the ability to replicate themselves using resources in the...

Shortform Exercise: Reflect on What You’ve Learned From The Cancer Code

The Cancer Code divides cancer research into three different Models—though each new Model doesn’t truly replace the old one so much as build upon it. Reflect on what you’ve learned about cancer from these Models and consider how you might apply that knowledge in your everyday life.

What was the most interesting or surprising thing that you learned about cancer from this guide?