Not the best answer but I read before the brain gets used to releasing hormones based on sweet flavor not by waiting to figure out what it actually is.
So based on what the brain is used to it'll still release the same enzymes and hormones yet not have the proper sugars to bind with, etc.
HttP00p t1_iy68dz3 wrote
Reply to ELI5: Sugar free drinks contribute to obesity? by YakkoRex
Not the best answer but I read before the brain gets used to releasing hormones based on sweet flavor not by waiting to figure out what it actually is.
So based on what the brain is used to it'll still release the same enzymes and hormones yet not have the proper sugars to bind with, etc.