Å·±¦ÓéÀÖ

The human immune system is very complex. So complex, that the author starts out by writing, "The immune system is too complicated for you to understand so I'm going to talk down to you." What a statement! And it's true--the writing is definitely easy to understand, because all of the interactions and components are spelled out in metaphors. This puts the concepts in human terms, ones that we all can understand. Just as a couple of examples:

"... the killer T cell is a dude with a hammer that bashes heads in while laughing maniacally."

or this quote:

"The awakening of the adaptive immune system usually begins in the lymph node dating pools, where dendritic cells covered in hot dog buns filled with antigens try to find the right T cells.

You get the picture. He compares bacteria with viruses using a simile; bacteria are like soldiers fighting in open battles at Troy, while viruses are hiding in a Trojan horse. But, to his credit, the author admits when the metaphors start to break down.

The book talks a great deal about immune cells killing themselves. For example, a dendritic cell spends a week or so in a lymph node to activate a helper T cell, before it kills itself.

The end of the book discusses the Covid-19 pandemic. There is a discussion about why some people died from the disease, others recovered with complications, most people had mild symptoms, and some had no symptoms at all. The reason seems to be that people's MHC II molecules are diverse, and they react to diseases differently. This gives the human species a better chance at survival when a terrible plague arrives.

Moreover, when you are looking for a partner, you use your sense of smell to ensure that he or she has MHC II molecules that are different from your own! This also helps to avoid inbreeding. Your partner's immune system is one of the factors that makes him or her attractive to you!

There is some good advice here about how to react to people who claim that they never get sick. Just nod politely and change the subject.

There is some really important information that should make anti-vaxxers think twice about their attitudes. It has to do with the pernicious side of measles. The number of deaths due to measles is increasing rapidly, due to anti-vaxxers. Children who get measles and recover have a greater chance of getting other diseases afterwards. That is because the measles virus kills memory cells. It deletes your acquired immunity. Measles is more highly contagious than the novel coronavirus. Measles also deletes the memories you gained from other vaccines. When it comes to measles, "what does not kill you makes you weaker, not stronger. Measles causes irreversible, long-term harm and it maims and kills children."

There is a discussion about why the immune system sometimes seems to act against your best interests. That is because humans evolved when today's big diseases did not exist. Instead, humans evolved when our worst problems were caused by parasitic worms. The author suggests that "One of the worst things to do late at night is to google infections by parasitic worms. You can ruin your life even more if you click on image search."

There are things you can do to improve your immune system. Stop smoking is number one. If you are obese, lose weight so your internal inflammation is reduced. Reduce your chronic stress, which is a big factor in weakening your immune system. When it comes to "boosting" your immune system, the author writes, "Boosting the immune system is a horrible idea that is used by people trying to make you buy useless stuff!" Luckily the danger is mild because nothing you can legally buy can boost the immune system. What you really want is a balanced immune system. Auto-immune diseases that are so prevalent now, and cancer, have to do with immune systems going out of balance. This book describes how and why. It also describes why allergies seem to be so prevalent in many areas, these days.

I highly recommend this book to all who care about their immune system. It gets rather technical at times, but it doesn't swarm in complexity.