[Dodoerabe]

After taking a blood sample the worried nurse has discovered that the oxygon level in his blood was a constant even though he stopped breathing altogether. Apparently during deep meditation the metabolism is so slowed down that the body does not need to breathe.

When one starts to practice zazen you are told to keep concentrated in your breath. Also to have a count of it... one, two, three... As you practice constantly there is a shift from breath as the focus of concentration to forget about breathing and just watching your thoughts. When this happens breathing becomes very very slow. Also you are not aware any more about your breathing or keeping a count on it. So I do not find neither dangerous nor impossible to stop breathing when one reach deep meditative states.