Who said gaining weight is a bad thing? Your tita shouldn’t think so too, so shock her with a thank you. Show them that there’s nothing wrong on being chubby because you are still the same wonderful person that you are.
Accept it as a compliment and show them how committed you are to eating. HAHA! But, seriously though, no matter what your size is, as long as you’re happy and motivated in life, carpe diem!