What kind of rationalists are you? There is one way to lose weight with tons of research backing it, and perfectly valid molecular explanation how it works - one ECA pill every morning until you're done, if you're losing weight faster than 1kg/week definitely eat more as that's not very healthy.

You should behave like proper rationalists now, read some pubmed, order some pills, and lose as much weight as you want. No significant side effects observed, unlike "natural" dieting which causes hunger, loss of willpower, loss of energy etc. Your appetite will be so low you'll have to use alarm clock to remind yourself to eat, but it won't hurt when you do, so no willpower expended either way. Ask any random bodybuilder for advice if you need it, they mastered the art of getting rid of fat without harming rest of the body.

I'm 79 kg (bmi 22) down from 106 kg (bmi 30) five years ago, so unlike 95% of after-diet rebouncers I know what I'm talking about.