After cancer treatment twelve years ago I could not absorb vitamin B12 in the normal way. I found out myself - no one told me! - that I had to use a high-strength supplement, but less often, of 1000 mcg. So I did that happily for years and years and it worked fine. Eight months ago I needed some more, and as my usual brand, Lamberts, did not seem to supply them at the time, I ordered them from Nutriseed. Bad mistake. I am now suffering from peripheral neuropathy which is no fun at all. I searched the internet and discovered there are two main versions of B12: methylcobalamin and cyanocobalamin. Methyl is excellent; cyano cheap rubbish. The Lamberts one I used to take says 'methylcobalamin'; the Nutriseed one I bought last spring did not say anything. It took me over 14 days to get hold of them and yes, Nutriseed contains the bad, cheap version, cyanocobalamin. Which did not work. I may never get rid of the neuropathy, such are the dangers of lack of vitamin B12. DO NOT buy from Nutriseed, however fanciful their paper packaging!