Probably hardly any, I would have thought. Maybe mash them up a bit (but not too much) so if the tough skins are broken I guess some nutrition will be gained. I love broad beans, which are large enough to take the skins off, but I don't know how easy they are come by these days.
Sweet corn is something that goes 'straight through' most people (certainly me!) and doctors use it to measure the 'transit time' I believe.
What about falafels & things like that, where the pulses are broken up a bit? Or hummus?
DS is 16 months & also trying to ensure he gets enough protein, fat, etc without overdoing it on cheese. He loves picking up peas too, unfortunately he loves it so much he turfs anything else out of the bowl looking for more of them!