the healthy noodles shown are made of konjac/glucomannan. it's down on the list of ingredients but only because it's an intense thickening agent in alkaline conditions and you just don't need a bunch. that brand adds a couple of other things to help with the texture but at their core they're still just konjac noodles.
i like these and use them pretty often:
they just add a bit of oat fibre to help with the chew