> when I have those 70+ (rare) or even 55+ (more often) hour weeks This is likely a different phenomena. You're burning more fuel by working longer. Especially

> when I have those 70+ (rare) or even 55+ (more often) hour weeks This is likely a different phenomena. You're burning more fuel by working longer. Especially if it comes with less sleep as well. The brain is quite a fuel-hungry organ and will crave sugars and carbs when stressed. If you're also sleeping less, you're burning more physical energy as well simply by being active longer. I regularly lose weight during hard weeks unless I compensate by eating more.