If we take youth as a proxy for health, and assume that the more youthful qualities are desirable, then it becomes apparent that sexuality is somewhat of a necessary evil.
It seems like my preferences have become progressively more sexual with age.
age 0 - 10: I like girls with pretty faces. I don't pay attention to their bodies at all.
age 11 - 14: I start paying attention to girls' stomachs. I start masturbating at 12.
age 15 - 19: I start to like breasts. I get a girlfriend.
age 20: I start to like women with small waists, and round curvy butts.