[npunt]

Bringing your own cup is also healthier, because paper cup linings are made of plastic that when exposed to hot liquids are likely to turn into microplastics.

My rule is: 1) keep hot stuff away from plastic, and 2) assume everything is/has plastic unless you know for certain.

[HDBaseT]

Reusable cups might be healthier assuming regular cleaning in the bottle, mouthpiece and lid.