Eating 3.3 servings or more of fruits and vegetables made research subjects notably more attractive.
Via LA Times:
On average, a difference of about 2.9 servings of fruits and vegetables a day was enough for the students to discriminate on the basis of healthy appearance, with more servings associated with looking healthier. Similarly, about 3.3 servings a day was enough for them to discriminate on the basis of attractiveness — with more servings associated with better looks. (A caveat: One weakness of the study is that most of the participants, and all the artificial faces, were Caucasian.)
There you have it: Hoover up 3.3 more servings a day of fruits and vegetables and watch what happens.