Technically, I've been attracted since I was very young according to my Mom. I apparently used to have a crush on the very fat babysitter. I don't recall her though.
I didn't see another fat woman/girl again until 8th grade. For some reason, our school was a bit of an anomaly and we never had a single fat girl in our school until 8th grade. Since then, I've known about it, but denied it until I was 20.
I selected "Since as long as I can remember." since I guess I was always that way.