01/03/2026
Have you ever lost weight, only to feel hungrier, more tired, and pulled right back to your old weight? There’s a biological reason for that.
Leptin is the hormone that tells your brain you have enough energy stored. When you lose weight and leptin drops, your brain doesn’t see success — it sees a threat. It responds by increasing hunger, slowing metabolism, and trying to get you back to your previous weight.
GLP-1 medications don’t change leptin, but they override that hunger response. This gives your brain enough time — usually 12 to 24 months — to accept a healthier weight as the new normal.
Once that happens, maintaining your results becomes much easier, even if you don’t use medication forever.