Comment by AstralStorm

It does. But not exactly in healthy humans by any sizable amount. Works pretty well for diabetics and prediabetics, and in cases of PCOS. Otherwise the effect is rather small and depends on prevention of diabetes and a few kinds of cancer.

It has a side effect of reducing muscle gains from exercise.

As for life extension by GLP-1 active drugs, it's much more of a guess. Mechanism is relatively similar. Side effects might not be...