true we all know the meaning of this... right~ enough .. this word has two meaning.. first is enough! (with an exclamation trying to say stop it! or just stop!) but base with your example.. enough is represents "being contented or satisfied" that is true enough~ the answerer is satisfied with the truth that we are not as slender as used to be as we get old. :) so you are right ^ㅅ^

"True enough" is what we call a colloquialism. It means EXACTLY the same thing as "True," but people in certain areas may prefer one over the other. I would only add that "true enough" sounds more casual, so I might use it more with friends and family than with my college professor, but "true" is fine for friends, family, professor and President of the United States. I need to correct your sample sentence though: "We are not as slender as used to be as we get old." We would say instead, "As we get older, we are not as slender as we used to be." OR "We are not as slender as we used to be when we were younger."

true enough= completely true/ I agree