What's one health habit you've started that's actually made a difference?

Cutting out sugar/refined carbs. No longer pre diabetic, lost weight and feel better.

I do several.
Most important one for me is to drink good quality orange juice. I need vit c daily for all sorts of reasons.

Next is I drink milk.
I get cramp if I dont, plus see too many people suffer from not drinking enough of it I assume.
I want good strong bones.

Well I haven't chosen it myself...but being diagnosed with Coeliac Disease and having to be gluten free. It's an anti- social and isolating auto immune disease. But at least now I'm no longer suffering malabsorption and stomach pains, vomiting and diarrhea with extreme weight loss. So being gluten free has made me feel more like myself. Although I still get very tired as at this age it takes much longer for the small intestine to recover, if it ever does completely. I've stopped drinking wine too..but do miss it but thought I'd best give my guts a chance to heal. It's dull though!