I woukd never feed it my rats, not so much because theres conclusive evidence that its bad but because I am personally very sensitive to it and it gives me horrible 3 day migraines. I know other people who are the same and it can cuase them to feel badly neusious, headches, shaky etc. Most people seem unaffected but can you imagine if a rat suffered from a reaction like that, a rat cant tell you hes got a headache or feels ill, you can tell jn more serious cases but you cant tell everything. For me its not worth the risk.
I do think theres a lot of strange studies done on asparteme out there, such as them apparently prooving it cant trigger migraines. For a start I dont think even doctors fully understand migraines so its odd they are so sure, and theres no way im not, in some cases ive had a 3 day migraine start 30 mins after drinking some sugar free lemonade ( one sip actually). Ive also barely had any migraines since cutting it out of my diet and I used to get them at least weeklh, now its a short one maybe once a month at most. It makes me think there are people out there desperate to provw it safe ratner than to do an unbiased study. Any way its a personal pet hate lol. For me sucrulous and stevi a is fine.