[nszceta]

Look no further than a basic hormone - leptin - to see how you can't give people more of it to lose weight while in fact leptin is the main mediator of obesity. Modern medicine hasn't produced a magic leptin pill to stop obesity because the biology is very complicated. You can't just inject leptin and lose weight (unless you don't produce leptin if you were severely damaged in an accident).

[JamesBarney]

Recent research suggests leptin doesn't really regulate body weight in both directions. It only really protects the body from weight loss, not weight gain.

Think of it like a thermostat with leptin being a temperature sensor hooked up to the heater, and the gravitostat is a temperature sensor hooked up the A/C. If you're trying to make the house cooler it doesn't matter how much you tell the heater not to turn on.

[UniverseHacker]

Why though? I’m a little out of date on this, but it seems leptin does strongly inhibit appetite when injected directly into the CSF, but mostly fails to do this in real life because of “leptin resistance.” For example, high triglycerides, block leptin transport across the blood brain barrier.

[moremetadata]

Ursolic Acid. Check it out!