The Body Summary

1-Sentence-Summary: The Body helps you become smarter about how to take care of and use this mechanism that lets you have life by explaining how it’s put together, what happens on the inside, and how it works.

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The Body Summary

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When was the last time you stopped to think about your body and how miraculous it is? It’s pretty wondrous if you think about it. Our bodies are mysterious and complex, even to those who spend their lives studying them. Bill Bryson’s book The Body: An Occupant’s Guide reveals some of the surprising details that cutting-edge science has told us about our bodies. 

You will be both entertained and fascinated as Bryson explores the human body and explains many of its remarkable abilities you probably don’t think much about. You’ll learn about everything from the ambiguous need we all have for sleep to what we know about the role of the millions of microbes that reside inside our body. By the time you’re done reading, you will marvel at the weirdness and utter brilliance of your human body. 

Here are the 3 coolest lessons I got to discover about our bodies:

  1. Your body is not your own, you share it with trillions of microbes that are vital to your survival.
  2. The brain is a mysterious and extraordinary organ you probably take for granted. 
  3. The new challenge for us as a species now comes from chronic diseases instead of communicable ones, but death is coming for us all anyway. 

How do our insides work? Let’s find out!

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Lesson 1: Trillions of tiny microbes share your body with you wouldn’t be able to live without them.

Most of us probably don’t like to think about the trillions of microbes living inside and on the outside of us. But really, we should be grateful for them. After all, we not only need them to function but to exist. 

One place they are particularly invaluable is in our digestive system. They not only help us break down food to make energy, but they make the vast majority of our digestive enzymes. In truth, microbes in our bodies are basically another organ. 

In addition to bacteria, we also have viruses. It’s okay though, because of the hundreds of thousands of viruses we know of, only 263 of them make us sick. We also are home to archaea, fungi, and protists, other microscopic organisms that do us little to no harm. 

With the advances of medicine in the last century, we have the ability to fight microbes with antibiotics. Unfortunately, antibiotics come with a weakness: they kill our good bacteria too. Also problematic is the fact that the more they are used, the less effective they get due to bacteria’s ability to develop resistance to them. 

Because of this, we are essentially in a crisis in modern medicine where antibiotics are prescribed too widely, leading to the rise of antibiotic-resistant “super-bugs.” Combine this with the problem of people not taking them as directed and the rise of antibiotics in farm animals we consume, and it is becoming a mounting threat for society.

Lesson 2: Your brain is a mysterious and sometimes misunderstood organ that has a miraculous design.

The whole body is really brilliant in its design, but one particularly remarkable component is your brain. It’s also a strange and isolated organ that is sealed off from the outside world. Around 75 percent of it is water, making it a soft, spongy ball that somehow makes us who we are.

There is a myth you often hear that we only use a small portion of our brain’s capacity. This isn’t even a little bit true. We use the whole thing, and it takes 20 percent of our energy to do so. But it’s also really efficient and only needs as many calories as a muffin to function every day.  

It’s composed of 86 billion neurons with trillions of connections between them. In short, there are three main sections: the cerebrum, cerebellum, the brainstem. The cerebrum is the two hemispheres that are responsible for personality, sensory processing, and emotions. 

This is where three of our key senses are based including hearing, sight, and smell. The cerebellum helps us balance and move. The brainstem makes sure that we stay alive by regulating breathing and sleeping. 

Our expressions, which come from the brain, are amazingly broad. Each of us has the ability to produce thousands of different expressions. The six that scientists believe to be universal include fear, surprise, pleasure, anger, disgust, and sorrow.

Lesson 3: We are now more threatened by chronic diseases than infectious ones, but our death will inevitably come either way.

In the year 2011, we crossed a threshold where there were more deaths from non-communicable diseases like heart disease than communicable ones like viruses. This shows us two things: we have come really far with medical science and fighting infectious disease, but we are also letting lifestyles play a bigger role in our deaths. 

Infectious diseases like smallpox used to be rampant in society. Smallpox took around 500 million lives in just the 20th century. But with advances in modern medicine such as vaccines, antibiotics, better sanitation, and a clearer understanding of diseases has helped us overcome the majority of these communicable diseases. 

Now, because of lifestyles changing to be more sedentary and unhealthy eating habits more present, we face different challenges like heart disease, cancer, and diabetes. These are known sometimes as mismatch diseases because they are the result of a discrepancy between modern life and our hunter-gatherer genes passed down through evolution. 

But avoiding death eventually becomes impossible for even the healthiest of us. Scientists tell us that it’s possible to get to the age of 80 with a healthy lifestyle alone, but after that, it’s mostly down to your genes.

Today, only one in ten thousand of us gets to the age of a hundred. Around 60 million people die a year. Of those deaths, one-fifth will be sudden, and another fifth are short notice. As for the other three, they will be more slow and gradual as conditions worsen.

The Body Review

This is one of those book summaries where I feel like I was only able to scratch the surface! The Body is jam-packed with fascinating facts and mysteries about our bodies. It’s also very well-written and witty, making it an easy and enjoyable read for anyone and everyone. It will leave you both fascinated and in awe of the body you probably don’t think much about.

Who would I recommend The Body summary to?

The 59-year-old who loves science, the 39-year-old doctor, and anybody that wants to know how their body works.

Last Updated on July 23, 2023

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Luke Rowley

With over 450 summaries that he contributed to Four Minute Books, first as a part-time writer, then as our full-time Managing Editor until late 2021, Luke is our second-most prolific writer. He's also a professional, licensed engineer, working in the solar industry. Next to his day job, he also runs Goal Engineering, a website dedicated to achieving your goals with a unique, 4-4-4 system. Luke is also a husband, father, 75 Hard finisher, and lover of the outdoors. He lives in Utah with his wife and 3 kids.