I don't know what dietary restrictions (or other protocols) you have in place, and I'm no nutritionist either... but if it's a case of not wanting to eat much (any?) sugar, say, then there are plenty of recipes out there, that feature low-cal (or no-cal) alternatives, whether natural or artificial. And if it's a case of avoiding fats, I'd suggest not doing so, but then that's me, lol. On the other hand, it's pretty easy - there are low fat alternatives to almost
every edible thing these days. Some of them actually taste okay too!
My guess is the former. In which case, maybe look at Stevia (the Reb-A kind, I think?) or sucralose, representing one decent option on either side of the fence. Oh, and you can use other things than flour... in place of flour.
A bit more info might help though.
edit: Hey, just a random recipe from my bookmarks, but if you like protein, and mint, and want to try a proteiny minty gelato... here's one
Is that even slightly close?