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May 27, 2021 - August 27, 2023
The brain is an organ of the body. So, if the insula creates an image of the body, that image must also include the on-board computer in our head. It has some interesting areas, such as those responsible for social empathy, morality, and logic. The social areas of the brain might give rise to negative feelings when we argue with our partner; logic regions might induce despair when we try to solve a difficult puzzle. In order for the insula to create a reasonable image of our self, it probably also takes in perceptions of our environment and experiences from the past. So, when we are cold, we
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So, the insula creates a picture of our entire feeling body. We can then use our complex brain to embellish this image. Bud Craig believes the picture is refreshed approximately every forty seconds. Through time, those images merge into a kind of movie—the film of the self, of our life.
Almost every body smell is, in fact, produced by bacteria.
Our gut’s microbiome can weigh up to 4½ pounds (2 kilos) and contains about 100 trillion bacteria.
The vast majority of our immune system (about 80 percent) is located in the gut.
all living things of any size have at least one other living thing that helps them in some way and is allowed to live on or in them in return. This explains why our cells are constructed in such a way that bacteria can easily dock with structures on their surface, and it explains why certain bacteria have coevolved with us over many millennia.
While 100 percent of the cells that make us up when we start life are human cells, we are soon colonized by so many microorganisms that only 10 percent of our cells are human, with microbes accounting for the remaining 90 percent. We cannot see this, because our human cells are so much larger than those of our new lodgers.
it will be about three years before the gut flora develops to the right level and then stabilizes.
if we are allowed to kiss and cuddle with our mother regularly, we will be protected by her microbes.
Children with insufficient Bifidobacteria in their gut in their first year have an increased risk of obesity in later life compared with infants with large populations.
In Japan, the gut population has entered into a trade relationship with marine bacteria. They borrowed a gene from their sea-living colleagues that helps break down the kind of seaweed used in Japanese cuisine to make sushi,
the composition of our gut population can depend to a large extent on the tools we need to break down certain foodstuffs.
IN TERMS OF our microbiota, we reach adulthood around the age of three.
Sometimes we alter our gut flora, and sometimes it alters us.
Our flora can take care of us, or it can poison us.
For bees, having more diverse gut bacteria has been a more successful evolutionary strategy. They were only able to evolve from their carnivorous wasp ancestors because they picked up new kinds of gut microbes that were able to extract energy from plant pollen. That allowed bees to become vegetarians.
They then go on to divide everything in the first drawer into three categories: eukaryotes, Archaea, and bacteria.
Modern biologists divide eukaryotes into six subgroups: crawly amoeboid microbes, microbes with pseudopodia (foot-like protrusions that aren’t real feet), plant-like organisms, single-celled organisms with little mouth-like feeding grooves, algae, and opisthokonts. For those unfamiliar with the term opisthokont (it comes from the Greek words for “rear” and “pole”), it describes the group that includes all animals—humans as well—and also fungi.
The most common eukaryotes found in the gut are yeasts, which are also opisthokonts.
There is one species of Archaea often found in our gut that thrives on the waste products of other gut bacteria and can glow.
bacteria make up more than 90 percent of the population of our gut. Biologists divide bacteria into more than twenty phyla or lineages.
Most of the inhabitants of our gut belong to one of
five phyla: mainly Bacteroidetes and Firmicutes, with a smattering of Actinobacteria, Proteobacteria, and Verrucomicrobia.
Everyone has their own personal collection of bacteria. It could even be described as a unique bacterial fingerprint. If you were to take swabs from a dog and analyze the genes of its bacteria, the dog’s owner could be easily identified with reasonable certainty.
Taken together, our gut bacteria have 150 times more genes than a human being. This massive collection of genes is called a biome.
no one needs breast-milk-digestion helpers forever. The latter disappear gradually after weaning.
The guts of obese people are often found to contain more bacterial genes involved in breaking down carbohydrates.
The genes of our gut bacteria also inform us about our body’s abilities. The pain-relief drug acetaminophen can be more toxic for some people than others: some gut bacteria produce a substance that influences the liver’s ability to detoxify the drug. Whether you can pop a pill to cure your headache without a second thought is decided partially in your gut.
Soy’s ability to protect against prostate cancer, cardiovascular disease, or bone disorders, for example, has now been proven. More than 50 percent of Asians benefit from this effect. Among people of European heritage, the beneficial effect is found among only 25 to 30 percent of the population.
PERSON’S ENTEROTYPE depends on the family of bacteria that dominates the microbe population of their gut.
Classical Chinese medical theory has always divided people into three groups according to how they react to certain medicinal plants, such as ginger.
The families of bacteria in our bodies also have different characteristics. They break down food in different ways, produce different substances, and detoxify certain toxins but not others.
Furthermore, they may also influence the gut flora by either encouraging or attacking bacteri...
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Bacteroides ARE THE best-known family of gut bacteria and often form the dominant population. They are experts in breaking down carbohydrates, and they possess a huge collection of genetic blueprints, which allows them to manufacture any enzyme they need to accomplish that task. Whether we eat a steak, munch a large salad, or chew on a raffia doormat in a drunken stupor, Bacteroides know straight away which enzymes they need. They are equipped to extract energy from whatever we ingest.
Their ability to extract the maximum energy from everything and pass it on to us has led to the suspicion that they may be responsible for an increased tendency to gain weight. Indeed, Bacteroides do seem to like meat and saturated fatty acids. They are more common in the guts of people who eat plenty of sausages and the like.
Parabacteroides.
This enterotype is also notable, among other things, for its ability to produce particularly large amounts of biotin. Other terms for biotin include vitamin B7 and vitamin H.
eating raw eggs causes vitamin H deficiency, which in turn can lead to skin disease.
I do, however, know who might possibly end up eating so much avidin in the future that they could have problems with vitamin H—pigs who accidently roam into a field of genetically modified corn. Genetic engineers have created transgenic corn with a gene that produces avidin to make it less susceptible to insect damage during storage. When pests—or stray pigs—consume the corn, they are poisoned. When the corn is cooked, it is no longer toxic, just like a good hard-boiled egg.
Biotin is also involved in some of the body’s vital metabolic processes. We need it to synthesize carbohydrates and fats for our body, and to break down proteins.
Skin, hair, and nail problems are not the only effects of biotin deficiency. It can also cause depression, lethargy, susceptibility to infections, neurological disorders, and increased cholesterol levels in the blood.
developing babies use up biotin like aging refrigerators gobble up electricity.
no scientific studies have been carried out to investigate how much biotin our gut bacteria provide us with. We know that they produce some, and that antibacterial medications such as antibiotics can cause biotin deficiency.
IN MANY WAYS, the Prevotella family is the opposite of Bacteroides. Studies have shown that they are more common in the guts of vegetarians, but they also appear in moderate meat eaters and in convinced carnivores.
A very serious lack of vitamin B1 causes a disease called beriberi.
It is now known that polishing rice removes the vitamin B1 it contains, and a diet made up predominantly of this kind of rice leads to an onset of symptoms within a few weeks.
While not resulting in serious neurological or memory disorders, a less severe vitamin B1 deficiency can cause irritability, frequent headaches, and lack of concentration.
More advanced cases can cause a susceptibility to edema a...
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The fact that our gut bacteria help supply us with essential vitamins means they are far more than just a load of flagellating sulfur-poopers—and that is what makes them so fascinating.
Ruminococcus
