The only source of the property is wearing the ring of slow digestion, though you can gain a similar effect by polymorphing into an inediate monster; the ring is inedible even for monsters that can digest its material normally, including you if you are polymorphed into such a monster.
The following information pertains to an upcoming version (3.7.0). If this version is now released, please verify that it is still accurate, then update the page to incorporate this information.White dragon scales and white dragon scale mail also confer slow digestion.
Slow digestion nullifies the ordinary consumption of one nutrition point per turn, but has no effect on nutrition consumption from all other sources, such as ring hunger - this effect does not stack and further reduce nutrition loss when wearing multiple sources of the property.
If a monster attempts to engulf and digest you while you have slow digestion, you will be expelled immediately (i.e. the ring slows your digestion); putting on a source of slow digestion while being digested will also cause that monster to spit you out.
- You get regurgitated! Obviously the <foo> didn't like your taste.
- You were engulfed by a digesting monster while wearing a source of slow digestion.
- You have slower digestion.
- You have slow digestion as viewed via enlightenment.