I’ve watched this documentary several times. I found it very informative, and it points out the scare tactics that are commonly used by idiots like Spurlock.
In “Super Size Me” Spurlock did include testimony from one man who said he’d subsisted on an all-McDonald’s diet and maintained a normal, healthy weight.
Spurlock himself (experimenting with the McDonald’s diet) was eating far in excess of what any normal person should have eaten.