Well, my appetite increases drastically at 50 mcg, and T3 can increase protein synthesis. I imagine to stay at say 8% bf year round is way easier. Plus comsuming more food at the same time equals more energy. And ramp up at 500 kcal rather than 100 kcal per week from cut to bulk (reverse dieting). I’m not the naturally lowfat skinny type either, and I have read that T3 usually works best at that body type, and not causing flatness. I really doubt 25-50 mcg is close to natural levels, but I guess that depends from person to person.