It all depends upon many factors -the educational, familial, sociocultural, &/or socioeconomic background of the man in question. Men from the upper socioeconomic class who are oftentimes more educated prefer thin, physical fit women. They want women to reflect their status. A thin, physical fit woman is considered to be the epitome of class & discipline as they have unlimited access to the highest quality of nutritious food, health care,& beauty regimens to assist them in being thin. They also believe that thin women are more healthier hence more beautiful than the heavier women whom they perceive to be lazy, sloppy, & unattractive.
Men from the lower socioeconomic classes who are less educated prefer women who are overweight as both aren't strict adherents to a proper diet & physical fitness. There are men from some sociocultural backgrounds who prefer heavier women because such women are viewed as healthier & more sensual than thin women. Men from some sociocultural backgrounds believe that heavier women make better cooks & are attracted to them because of this. They feel that thin women really don't know their way in the kitchen & may see them as undernourished.
Among the middle class, the preference for women vary. The more educated upper & solidly middle classes know the importance of a nutritious diet & exercise. So it goes to reason that such men want a physical fit, thin woman. The lower middle class know less about nutrition & the importance of exercise so such men tend to be attracted to a heavier, even overweight woman.