My wife's self body image tends to frustrate/annoy me?

My wife is utterly beautiful in my eyes. Sometimes she makes comments about herself like how she would like to have bigger breasts and better skin. I don't like it when she does this and I continue to tell her I love her just the way she is. She is a striking woman, but I don't know why she cannot be content with her beauty.

I try to make it better, but it seems it is not enough. I get annoyed and she notices.. What do I do to make it better for the both of us?