All capping agents/reducers we use are safe for humans to ingest.
Gelatine provides a very strong stabilizer that keeps the silver particles tiny and keeps the Colloidal Silver good for a very long time.
Karo works well but only for PPM's of 20 or less though it works well into the higher PPM's IF you're going to then gel-cap as the gelatine becomes the strong stabilizer, which Karo isn't. Above that, for non-gel-capped, use maltodextrin as its a MUCH better stabilizer.
I've never made malto reduced non-gel-capped higher than 80PPM so I can't say how high you can go and keep it stable and good for years but I've had 80PPM that still looks like the day I've made it for years.
And yes, if you prefer, you can use malto as the reducing agent for gel-capped. I've taken it as high as 120PPM and it seems to work well.
There is some research that suggests adding gelatine at the beginning of a higher PPM run yields SMALLER silver particles, closer to 10nm, which is better. I tried it recently instead of adding it after the run and I'm hooked. The result is MUCH clearer and very transparent compared to what I get when I add the gelatine after. The talk that the gelatine slows down reduction may be over-stated unless this applies mostly to higher current, higher PPM runs. The runs I did were at 7.5ma to 120PPM and it may have slowed down reduction a little for being in solution from the beginning of the run but from my observation, not by a whole lot. I also didn't have to do any flame cleaning of my anode half way through the run. This too might be more applicable to the "on the road to 320PPM" path (wink) and I have no desire nor need to ever make 320PPM. 120PPM is plenty good enough for my needs.
Gelatine is also a better stabilizer and the human stomach does not digest nor manipulate protein, which gelatine is (no, vegetable gelatine will NOT work) so everything you ingested gets into the small intestine where a couple enzymes digest the protein and let out the silver to be absorbed.
100% or nearly so of what you ingested makes it into the small intestine though there is no easy way to ascertain what the actual absorption rate into the blood is though given non-gel-capped has been shown to have as much as 25% of the particles agglomerate (stick together) into much larger "chunks" that are not absorb-able, due to the actions of the stomach, if you can get all of it into the small intestine without changing the particle size, which is what gelatine affords you, you stand to absorb a goodly amount of that 25% you'd have lost in the stomach with non-gel-capped.