With some, perhaps. For most, however, it boils down to preferences and employment. These are "on average," so no one be an asshole by reminding me "not all men/women." Men eat like shit; we shy away from anything "diet," "sugar-free," or "light"; we prefer high-calorie beer; we prefer meaty, fatty meals (sate hunger better for longer); we have more physically-demanding jobs; and we're responsible for most of the "action" when it comes to sex. Women, on the other hand, eat much healthier; prefer no- and low-cal beverages; prefer lower-calorie wine/mixed drinks and require less alcohol; prefer carb-based meals (terrible at sating hunger) over "barbaric" meaty, fatty meals; and don't have physically-demanding jobs. Basically... Guys have plenty of options when it comes to reducing caloric intake. It's not just our size, but we're burning more calories when it comes to employment and sex. When we make changes by reducing or axing certain things, we get greater results for weight-loss. Women, however, have far fewer options since they're already much more health-conscious and aren't as active at their day jobs or in the bedroom.