It was Christmas week 1990 in Oakland. Steven Bloom was wandering through The Lot, that timeless gathering of hippies that springs up in the parking lot before every Grateful Dead concert, when a Deadhead handed him a yellow flyer.
Because of the general safety of the vitamin, upper limits for normal intake do not exist. If your blood values for the vitamin fall below a range of 170 to 250 picograms per milliliter, you may develop a B12 deficiency.
Her B12 level was slightly over 200 picograms per milliliter (the normal range is considered 200 to 800 pg per ml). After several weeks of B12 injections, then 1,000 milligrams daily in pill form, her B12 is now over 600 pg per ml and she says she feels better.er B12 level was slightly over 200 picograms per milliliter (the normal range is considered 200 to 800 pg per ml). After several weeks of B12 injections, then 1,000 milligrams daily in pill form, her B12 is now over 600 pg per ml and she says she feels better.