Why weight loss slows down, and what it usually is not

Almost everyone slows down eventually. The reason is usually much more boring than the internet suggests.

A lighter body costs less to run. Every pound you lose takes roughly 13 calories a day off what you burn. Lose 20 pounds and you are burning about 270 fewer calories a day than when you started, so eating the same amount is now a much smaller deficit. Nothing has gone wrong. The arithmetic just moved.

Then there is everything else. Portions creep up over a few weeks without anything feeling different. Water shifts from a new workout routine, more salt, poor sleep, or a period can hide real fat loss for a week or two. And sometimes not enough time has passed for the trend to separate from normal daily noise.

Your metabolism adapting is real, but it is far down this list, and it is smaller than most people think. It slows loss, it does not stop it. Anyone selling you a fix for a "broken metabolism" is selling something.