You can, but it'd be obnoxious and rude af. Humans in general are really good at storing fat because of starvation selection in early humans. Most people, at least in "developed" countries, are over-nourished and/or don't have a balanced and diverse diet like our ancestors did. That's a great recipe for obesity and obesity-related illness that I won't blame on anyone. but ofc, that's where public health education and policy comes in. we can inform people of how their bodies work and what's in their food so people can make the best diet, exercise, and other lifestyle choices they can to counteract any genetic predispositions that might be stacked against us.