In a world where money has no value, everyone can afford to have proper nutrition and medical care, reducing obesity. Furthermore, if one is in a pseudo military organization, one would probably have to be physically active and fit.
Beyond that, Starfleet is supposed to be the best of the best of the best. While that doesn’t extend the aesthetics it is reasonable to believe that people so driven would tend to look good.
In a world where money has no value, everyone can afford to have proper nutrition and medical care, reducing obesity. Furthermore, if one is in a pseudo military organization, one would probably have to be physically active and fit.
Beyond that, Starfleet is supposed to be the best of the best of the best. While that doesn’t extend the aesthetics it is reasonable to believe that people so driven would tend to look good.