The strange phenomenon of vitamin B12

  Variation vitamin intake
  of vitamin is required for one of the various nutrients the human body, is a necessity. In order to ensure that the body is not deficient in vitamins, people strive to ensure a balanced diet and even eat vitamin tablets. But in fact, vitamins do not all need to be taken from the diet. For example, vitamin Q (also known as coenzyme Q10, ubiquinone) is very important to the human body (it plays an important role in the conversion of nutrients into energy in the granules), but it is not necessary because the human body can synthesize itself to create this kind of Biomolecules. In other words, vitamin Q can be ignored in the daily diet.
  In fact, it is common for most animals, especially primates, to synthesize and absorb vitamins by themselves. Vitamin C is an example. It is not necessary for most animal diets, only for human diets. It is estimated that the genetics of human ancestors in ancient times may be mutated, destroying the genes that synthesize vitamin C in the body, leading to the need to take in the diet.
  From the perspective of the survival of the fittest, these so-called evolutions are undoubtedly problematic, which increases the dependence of humans on specific foods in the outside world, and to some extent this leads to a decline in viability. Among these mutations, vitamin B12 is one of the most serious manifestations.
  Both necessary, and important
  vitamin B12, vitamin is the only metal element. Its molecular structure contains cobalt ions, so it is also called cobalamin, which is the only biological use of cobalt. It is extremely important for human survival. Every cell in the human body needs to operate normally, and it is inseparable from vitamin B12.
  Vitamin B12 is indispensable in the production of fatty acids, amino acids, and the replication and repair of DNA. Moreover, many fatty acids are used to make myelin, which re-encapsulates neurons and nerve bundles, which makes the nervous system particularly dependent on vitamin B12.
  A serious consequence of the lack of vitamin B12 is malignant anemia. Bone marrow stem cells can divide to produce red blood cells, which is one of the most active dividing cells in the human body. In the process of cell division, when DNA replication is impaired, if there is no repair of vitamin B12, the number of red blood cells will be greatly reduced, the human body function will be disturbed, and the immunity will also decrease. If pernicious anemia lasts for a long time, it will endanger life.
  On the other hand, plants and fungi do not require vitamin B12, and they do not contain vitamin B12. That is to say, from a dietary point of view, vitamin B12 can only be taken from animal foods, which is the only nutrient element in human diets that must be taken from meat. Most animals contain vitamin B12 in their bodies, and soy products are partially fermented. For strict vegetarians, not eating eggs, milk or soy products is very dangerous.
  Derived from microorganisms manufacturing
  since animal foods are the only source of vitamin B12, then herbivores in nature but also how to survive?
  In fact, the vitamin B12 in meat foods is not made by animals themselves. It is synthesized by microorganisms, and the synthetic site is in the intestines of animals. There are bacteria in the intestines of animals, and they are symbiotic. Animals provide food and shelter for bacteria, while bacteria produce vitamin B12 during metabolism, and animals absorb and use it. Herbivores rely on this way to survive.
  This symbiotic model is no stranger to the human body. The synthesis of vitamin Q is like this, and vitamin K is also. They are all produced by the intestinal bacteria of the human body and are directly absorbed by the body in the intestines. Vitamin K plays an important role in blood coagulation, but because it can be produced and absorbed in the body, it is not very popular, and it is not “famous” in the nutrition list.
  If vitamin B12 is also the case, is human survival more powerful? In fact, many bacteria that produce vitamin K also produce vitamin B12. So why can’t people produce vitamin B12 in the human body?
  Intestinal transformation
  Studies have shown that the problem lies in the absorption process, and the human digestive system has a “dysfunction.” For humans, bacteria that make vitamins K and B12 live in the large intestine, but the place where they can be absorbed is not the large intestine. Vitamin K can be absorbed in the large intestine, but vitamin B12 can only be absorbed in the small intestine, but not in the large intestine.
  The small intestine is located in front of the large intestine, and food cannot enter the small intestine from the large intestine during digestion. Bacterial vitamin B12 eventually enters the toilet with food debris. The study also found that the cobalt content in human feces is very high enough to meet the daily vitamin B12 requirements of the human body. Of course, no one wants to use feces as a source of vitamin B12.
  How this digestive dysfunction is produced is still a mystery and science is difficult to explain. Most of the primates closest to humans are herbivores. Archaeology also found that early humans were mainly vegetarian, so human ancestors could certainly absorb vitamin B12 produced by intestinal bacteria, otherwise they would not survive.
  Later, when humans began to eat meat, accompanied by hunting and animal husbandry techniques, the vitamin B12 provided in the diet was gradually stable and rich, so scientists speculated that it was at this time that the function of absorbing vitamin B12 gradually shifted from the large intestine to The small intestine, then the large intestine is “gloriously retired”.