Why is there so much vitamin B12 in Jimmy Joy Plenny?

The level of vitamin B12 in Plenny is high because, sadly, this vitamin can't be easily obtained through a vegan diet. B12 is most commonly present in animal products, such as dairy or meat [6-8]. This is because animals can produce vitamin B12 in the gut. Humans, however, lack specific bacteria needed for that. But luckily we can produce B12 synthetically without using animal products too [7, 8]! 

How is B12 absorbed by the body?

Furthermore, the synthetic form of vitamin B12 (called cyanocobalamin ) can't be absorbed by the body directly. It must first be broken down into the - bear with us - two bioactive coenzymes. There are - bear with us - four metabolic steps necessary for this process. These steps form a metabolic disadvantage, and on top of that, a part of the B12 gets discharged before it's even converted. So in the end, an uptake of 140 mcg cyanocobalamin provides the body with - bear with us - only 2,76 mcg of cyanocobalamin [1-5].

Why do we need vitamin B12 anyway?

As you may remember from biology classes, DNA encodes all information to
build and maintain your body. Vitamin B12 enables the production of DNA's
building blocks, specifically Thymidine (T) [6]. Insufficient B12 can result in less available oxygen in your body, causing tiredness.

How much B12 do you need?

According to the latest research in Europe by the EFSA it is recommended for adults to get 4 to 7 μg of B12 per day. We added 29,3ug per 400kcal of Plenny, which is 11.2 times that amount. This may seem a little too enthusiastic, but no worries, it's by no means dangerous. What you eat is not necessarily the amount of vitamin that reaches your blood. Food needs to be picked up by the epithelial cells in our gut. As we already mentioned, in the case of synthetic vitamin B12, this process causes a great loss. Eventually, only  ~40% what we take in will be effectively absorbed [7].


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steady concentrations of vitamin B-12-related biomarkers in a healthy young
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2(3): p. 299-316.
8. Moll, R. and B. Davis, Iron, vitamin B12 and folate. Medicine, 2017. 45(4): p. 198-203.

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