I dramatically cut down my consumption of added sugars several years ago (added sugars are, as the term suggests, those "added" where they wouldn't be on their own -- eg a bowl of blueberries on its own clearly has sugars. Package those blueberries in a preserve and the preserve will have "added" sugar, not just the sugar from the blueberries themselves).

On the one hand, I'm afraid to say that I can't report any dramatic night and day difference. I do have in general more energy, better dental health, etc, but subjectively that all felt _slightly_ better, not click-baity better. On the other hand, I can report it hasn't been all that dramatic -- I didn't upend my life, made what really felt more like slight changes. Probably the biggest change for me was breakfast -- instead of carbs it's generally Greek yogurt, frozen fruit, nuts, and raisins (for sweetness), and coffee. I also check labels more -- who knew, for instance, that tomato soup had so much added sugar!

I take that as a win since, objectively, it _is_ much healthier to have less added sugars in my diet, and I got this gain without anything overly dramatic or disruptive. And it kicked off a gradual changing of other habits -- I got back to going to the gym regularly a few years after that, and have gotten better at keeping a regular bed time.

The tl;dr I'm trying to make here -- smaller, gradual changes do make a difference, are worth doing, and don't have to be dramatic (and are easier to stick to).