More on this book
Community
Kindle Notes & Highlights
Read between
June 8 - June 13, 2022
The immune system is the most complex biological system known to humanity, other than the human brain.
Liong and 3 other people liked this
In the animal world, sponges, the most basic and oldest of all animals, which have existed for more than half a billion years, possess something that probably was the first primitive immune response in animals.
The total surface area of your skin is about two square yards (meters) (about half the size of a pool table)
Your real weak points to infections are your mucous membranes—the surface that lines your windpipe and lungs, eyelids, mouth, and nose, your stomach and intestines, your reproductive tracts and bladder.
on average there are about 200 square yards (meters) of mucous membranes in a healthy adult (about the same as a tennis court), most of them being your lungs and your digestive tract.
if we took all the blood vessels and capillaries from your body and laid them out in a straight line, they would be a baffling 10,000 miles (16,000 kilometers) long—three times the circumference of Earth—with about 1,400 square yards (1,200 square meters) of surface area.
Some of the most common proteins are extremely plentiful inside your cells, with up to half a million individual copies. Others are specialized and exist fewer than ten times in total.
The vast majority of your cells actually do not have DNA. Red blood cells in particular make up around 80% of your cells by pure numbers, and they don’t have a nucleus, because they are filled head to toe with iron molecules that transport oxygen.
according to even the most conservative estimate, bacteria have at least ten times more mass than all animals combined. In one gram of soil, there are up to fifty million bacteria doing their thing.
We have data from a Boston hospital from 1941 that shows that 82% of bacterial infections of the blood resulted in death.
Cells killing themselves is nothing special in your body, every second at least one million of your body cells go through some form of controlled suicide.
Depending on your age, it takes your skin between thirty and fifty days to completely turn over. Every single second, you shed around 40,000 dead skin cells.
A healthy individual’s skin holds up to forty different bacteria species, as different areas of your skin are drastically different environments with their own specific climates and temperatures. Your armpits, hands, face, and buttocks are pretty different places and house different guests.
Overall, an average square centimeter of your skin is home to around a million bacteria.
mitochondria, the powerhouse of the cell, were ancient bacteria that merged with the ancestors of your cells to become a symbiotic organism. Today they are organelles inside your cells that provide the cell with useful energy. Your immune system still remembers them as bacteria though, as intruders that have no business being outside cells. So if your cells burst and your immune system detects mitochondria floating around, your immune cells will react
A signal needs to pass a specific threshold to compel a cell to do something. This is one of the ingenious regulatory mechanisms of your immune system.
Your heart pumps and transports nearly 2,000 gallons of blood through your body every single day, while your lymphatic system only transports around three quarts from your tissues back to your blood.
bean-shaped Lymph Node megacities—the organs of your immune system. You have around 600 of them spread all over your body.
Monocytes are basically reinforcement cells that can transform into Macrophages and Dendritic Cells. About half of them patrol in your blood right now where they represent the largest single cell that floats through your cardiovascular system.
All in all, around 30% of your poop consists of bacteria—and a lot of them have been clumped up by IgA Antibodies (most disturbingly, around 50% of them are still alive when they leave you).
Influenza A has specialized in infecting the epithelial cells of the respiratory system in mammals. Since this includes humans, influenza A has been responsible for four major influenza pandemics in the twentieth century alone,
There are diseases though that are able to destroy your immunological memory. To kill the memory cells that defend you. It is tragic that one of these diseases is currently making a huge comeback: Measles.
Globally, measles killed more than 200,000 people in 2019, most of them children, a 50% increase since 2016.
If you have measles, you’re so contagious that 90% of all susceptible people that come close to you will be infected just by being in your vicinity.
In the twentieth century alone, smallpox killed more than 300 million people,
Think of Ebola, even this pretty disgusting and horrible disease needs about six days to kill you. Your immune system has the power to kill you in about fifteen minutes.
When your immune system loses its self-composure, it becomes deadly, killing a few thousand people by anaphylactic shock each day.
There are nearly 300 species of parasitic worms who can infest humans. And while only around a dozen of these species are widespread, they still infect up to two billion people, close to a third of humanity.
The latter half of the twentieth century saw two really weird and counterintuitive trend lines in developed countries. While dangerous infectious diseases like smallpox, mumps, measles, and tuberculosis were successfully pushed back and in some cases got to the verge of elimination, other diseases and disorders began to grow or even skyrocketed. The rates of diseases like multiple sclerosis, hay fever, Crohn’s disease, type 1 diabetes, and asthma have increased by as much as 300% in the last century.
It seems like you can draw a direct line from how developed and rich a society is to how much of its population suffers from some kind of allergy or autoimmune disorder.
The number of new cases of type 1 diabetes is ten times higher in Finland than it is in Mexico, and 124 times higher than in Pakistan. As many as one in ten of all preschool children in Western countries suffer from some form of food all...
This highlight has been truncated due to consecutive passage length restrictions.
virtually every infectious disease we know today arose in the last ten thousand years. From cholera, smallpox, measles, influenza, and the common cold to chicken pox.
Even the mere term “strong immune system” is a misnomer. Over everything else, you want a balanced immune system. Homeostasis.
At least for now, there are no scientifically proven ways to directly boost your immune system with any products that are easily available. And if there were, it would be very dangerous to use them without medical supervision.
chronic stress seems to disrupt the ability of the body to shut down inflammation and causes chronic inflammation.
if you are still looking for ways to boost your immune system, an actual tangible thing you can start doing today is to try to eliminate stressors in your life and to take care of your mental health.
benign tumors do not invade other organ systems, like cancer cells.
Cancer can emerge from basically every type of tissue and cell in your body. And since you are made up of many different types of cells, it is not really a single type of cancer, but hundreds of different ones.
Almost one in four people alive today will get cancer during their lifetime. And one in six people will be killed by it.
All in all, the easiest way to get cancer is to be alive long enough. It is statistically impossible to not develop some cancer at some point in your life, even if it ends up not being the cause of your death.
In 2017 only 12% of all cancer deaths happened to people younger than fifty. And so, if you are lucky enough to get old, you are almost certain to have some amount of cancer cells inside you, it might just be that other things kill you before those get a chance.
smoking is bad in many different ways that are closely related to the immune system. In a nutshell, you break the mechanisms that protect you against disease and cancer, while making it more likely to get an infection or cancerous cells!
nicotine, the magic and vile substance that makes smoking addictive, suppresses your immune system. It makes your immune cells slow and ineffective.
