aspartame triggering insulin response?

i stumbled on some articles (nothing peer reviewed) recently citing some studies somewhere, one said baldly that 25% of people sampled have an insulin response to aspartame (equal).  The release of insulin, if i understand correctly, stops or prevents fat loss?

can anyone point me toward some sources for these studies?  or is it one of those things that get cited so often people accept it as fact, but has no actual basis?

i'm not a fan of aspartame, never liked the taste, gives me headaches, always kind of suspicious of the health impact, it gets a lot of bad press. 

i thought this might be relevant to the recent post querying about diet sodas as well.

About two weeks back I read an article on a low carb site about sucralose (splenda).  It branded splenda as the insulin villan along with sugar alchohols and vindicated aspartamine (nutrasweet).  Just like what you heard, no links to any reputable studies.

I use both and I like both.  As long as they don't slow my wl, all things in moderation.  I'm very 'carb sensitive' (my own term), but I've noticed no difference in progress when I use these and when I don't.