The only nutrient that vegan cannot consume is vitamin B12.


Vegan only receives nutrition from botanical foods. There are nutrients (vitamin B12) that can be taken from animal foods but not from plant foods. I take vitamin B12 as a supplement.

Here, I will also introduce the function of vitamin B12, folic acid, and recommended nutritional yeast.

Recommended for such people!
  • Vegan doesn’t eat meat and fish, but I’m worried that I’m nourished properly!
  • What is Vitamin B12? How does it work? What should I take from?
  • I want to know recommended nutritional east!
  • Is folic acid often heard with vitamin B12 important?

I’m careful about vitamin B12, so I’d like to introduce it this time.

Where Does Vitamin B12 Come From

Vitamin B12 in the soil

Vitamin B12 is originally made by microorganisms in the soil.

An animal that eats plants with soil will get vitamin B12, so if you eat that meat, you can get vitamin B12 through it.

However, due to soil pollution, the amount of vitamin B12 in the soil is now low.

Therefore, vitamin B12 has been added to the livestock feed.

It can be consumed by eating soiled vegetables grown in high quality soil.

However, the vegetables that are lined up in the supermarket are so washed that they cannot take vitamin B12.



For that reason, vitamin B12 should be taken as a supplement.

Vitamin B12 can be consumed in trace amounts, and according to the “Japanese Dietary Intake Standards”, recommendation is 2.4 μg per day.

However, many vitamin B12 supplements are 2,000 μg/tablet. Therefore, the content per tablet is so high that one tablet is taken in half. Many supplements are so soft that they melt under the tongue.

Therefore, even if you do not use a pill cutter, which is a tool for cutting tablets, you can easily halve it by breaking it with your fingers. Also, supplements are usually red, the color of vitamin B12.

Functions of vitamin B12


Vitamin B12 plays a role in maintaining the functions of cranial nerves and peripheral nerves, and also has a hematopoietic effect.

This hematopoietic action does not work without folic acid.

Therefore, I think it is more effective to take supplements after eating meals containing folic acid-containing ingredients such as beans and green vegetables. Vitamin B12 deficiency can cause pernicious anemia, impaired nervous system function, and later Alzheimer’s disease.

Vitamin B12 is absorbed in the stomach by combining with a protein called “intrinsic factor”. People who have poor stomach function and elderly people often have less secretion of intrinsic factor. Therefore, if you take vitamin B12, it will not be absorbed and you will be deficient in vitamin B12.

Therefore, elderly people and those with poor stomach function need to be aware of ingestion. It is also recommended for people who don’t eat much meat or vegetarians.

Here are the types of vitamin B12.

2 types
  • Active vitamin B12 ➡ Absorbed in the body
  • Inactive vitamin B12 ➡ Difficult to be absorbed in the body

Nori seaweed also contains vitamin B12, but since it is inactive, it is not absorbed by the body. (From research data at

What is Nutritional East


Nutritional yeast is a non-living yeast with a cheese flavor. It also contains vitamin B12, which makes it popular among vegans.However, it has been suggested that this nutritional yeast is an inactive form that is not easily absorbed by the body.

Also, nutritional yeast contains folic acid as a vitamin B enhancer, but there are two types of folic acid.

2 types
  • Folate ➡ Natural origin
  • Folic Acid ➡ Artificial production

In Japan, these two types are collectively called folic acid, but they are sold under different names overseas.

Folic acid increases the risk of colorectal cancer, breast cancer, prostate cancer, childhood asthma, birth defects of the fetus, etc. I will. In particular, it is said that if “folic acid” is taken during pregnancy, the risk of death from breast cancer will be doubled compared to women who do not take it. (British Medical Journal 2004)

Therefore, when purchasing Nutritional Yeast, make sure that the folic acid contained is folic acid or foreic acid, and be careful.


I use the one sold online at this store in Hamamatsu City, Shizuoka Prefecture.

Japan’s first additive-free nutritional yeast.

This is a store I thought I could trust.

( ※I’m not a turn around in this shop.


If you are interested, please check out Nutritional East yourself. There are various information and experiences, so I can not say whether it is good or bad.


It is said that the most efficient method is ingestion from supplements.

Vitamin B12 is water-soluble, so it is not accumulated in the body and is excreted as urine. Therefore, it should be taken regularly. I take supplements once or twice a week.

I think it’s a hassle for people who don’t take supplements on a regular basis. I was like that at the beginning.

But it’s not a fixed time every day like a pill, just a tablet when you remember it, so it’s not a burden.


If you’re trying to go vegan, don’t forget to buy vitamin B12 supplements.