Vitamin B12(ビタミンB12)

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Characteristics of nutrients

  • It is mainly present in animal foods (rarely in vegetable foods)
  • Water-soluble vitamin
  • Oxidized by light and air
  • Called “vitamins of hematopoiesis”
  • Helps to synthesize hemoglobin
  • It is based on the synthesis of amino acids together with folic acid
  • Attention when the stomach is weak because it is absorbed together with the secretory substance of the stomach

Function of nutrients

  • Prevention of malignant anemia
  • Synthesize nucleus of nerve cell
  • Protein synthesis
  • Synthesis of nucleic acids
  • Synthesis of erythrocytes
  • Preparing the rhythm of sleep

When nutrients are deficient

  • Malignant anemia (headache, dizziness, nausea, loss of appetite)
  • Numbness of limbs, decrease of concentration
  • Stiff shoulders, low back pain, neuralgia

When nutrients overdose

  • No worry of excessive intake
  • Even if overdosed, it is not absorbed more than necessary

Food that contains a lot of Vitamin B12

FoodstuffIngredient per 100g (㎍)
Shijimi (boiled)81.6
dried young anchovies64.5
ark shell59.2
seasoned laver58.1
sujiko(salmon roe)53.9
Beef liver (raw)52.8
Short-neck clam52.4
Sweetfish Internal organs49.6
Sakhalin surf clam47.5
ikura(salmon roe)47.3
Hard clam45.4
Chicken liver (raw)44.4


  • Soluble in water with water soluble vitamins
  • Much contained in animal food
  • Even if you take too much, it is not absorbed more than necessary
  • It is absorbed along with stomach secretions and tends to run out when the stomach is weak
  • Involved in amino acid synthesis with folate
  • It is water soluble, so it is recommended that you can eat the whole soup