Since we're discussing the 80/10/10 diet, I read the B12 chapter again and I will try to summarize
what this particular book says since so many people care about B12.
According to the "80/10/10 diet" vitamin B12 can be obtained from natural plant sources.
Vitamin B12 is made by bacteria. It was not discovered until 1948. In 1942 some pharmaceutical companies
started using leftover chemical weapons from WWII as pesticides and insecticides. Plants soak up vitamin B12
(among other vitamins) from the soil where the said bacteria live. As a result of the use of chemicals, the soil has been sterilized
so the plants cannot extract the B12 from the soil.
Therefore most nutritional researches encounter no vitamin B12 in plants.
Organically grown plants cultivated in an organically composted soil can contain plenty of vitamin B12.
We can also obtain it from the environment:
A hundred years ago people did not wash their food so much and some of the soil which clung to carrots, lettuce,
celery and such got eaten and it often contained B12. B12 can also be contained in the dirt which
accumulates around the stem of apples, pears, peaches, apricots, etc.
(That is what I meant about getting it from the environment. For example, I wash my fruit in the city
but when I'm on my granny's farm, I would just wipe the dirt off and eat it. Some friends of mine and
I went to the mountains on bikes this Saturday and I bought some apples from a local shop in a village -
an "industrial shop", and I just wiped them and ate them. There's some chance that I got B12 from
the area around the stem. Still, it wasn't an organic shop so who knows
So yes, now that you made me read this again, I know more about B12:)
Moral of the story: stick to organic farming, to produce from organic soils and you'll have no B12 deficiency!
This would also explain how vegans did not die enmass from B12 deficiency before its discovery in 1948.