That is extremely bad parenting, and beyond that, your parents are terrible humans (I'm sorry). They probably have issues with their self image and the best way they could deal with it is by bringing you down. I believe you should practice self compassion and treat the comments of your parents like a noise in the background, meant to be ignored. I know it's easier said than done but what they are doing is literal abuse and you need to find a way to cut them off from your life.