'Back in 1994 when I was focusing on learning as much as I could about vitamin B12, an experiment came to mind which I decided to try on myself. I saw a bottle of DMSO (dimethylsulfoxide) on the shelf of my health food store and remembered that DMSO is not only absorbed directly through the skin, but it also would carry with it any impurities dissolved in it. This can be a serious problem if the impurities are toxic.
However, I also realized that if I dissolved vitamin B12 in it, it might carry it directly to my blood stream through my skin. I tried it and the results were dramatic for me, far greater than any impact I had ever felt from oral or sublingual tablets. I put some of my vitamin B12 tablets obtained at a health food store into a two liquid ounce bottle with an eyedropper and filled it with DMSO. It took a couple of days for the tablets to fall apart. Once they did, I put an eyedropper load on one arm and rubbed it in. In approximately one hour I started to feel very good, which was a sense of general strength and well being. This lasted all day.
When I tried it again the next day, I got no such feeling. I also didn't experience any bad effects either. Since I knew that approximately one month’s requirement of B12 is stored in your liver, I reasoned that my system was simply fully supplied with Vitamin B12 and that I wouldn't need to use it again for a month or so. When I tried it again a month or so later, I got a significant boost from it again. Since then I have continued to use it on a once every month or so basis.'
We need extremely low amounts of B12. Vitamins can to a certain degree be absorbed through the skin. Maybe one of several reasons that some vegans in 'primitive' cultures (the earlier mentioned Iranian case) don't develop signs of B12 deficiency simply is that they both get more sunlight, are exposed to organic dust from soil (through their mouth/nose*), and maybe walk barefoot and even are in touch with the earth with their hands daily, and therefore absorb a tiny bit of cobalamin from the soil?
*Some people insist that the best way to absorb B12 actually is by using B12 nasal spray - but I don't know if this is correct.