Why is it ok for guys to be overweight but not girls?

Socialy acceptable? Well among men there is nothing more horrible than being underweight stick. That, if you ask me makes it harder for guys. Not ok to be fat or a stick. Women seem to only be judged for overweight (they just get way more obsessed about it). But women with little extra have still more takers than fat boys do.
And as "socialy acceptable" is maybe still bit more determined by men in society, it causes that its womens figure that is looked more closely. Men don't that much care what men look like.

Generally speaking, women are less discriminating than men are when it comes to looks. It goes straight back to evolutionary psychology. Men look for women that will produce good babies and women look for men that will be able to provide for and protect their babies. Deep down our brains still respond to our environment just as they did 20,000 years ago. From a man's perspective, logically we may look for more than just a pretty face, but a nice personality isn't what's going to make us walk across the street to ask you your name and see if you want to grab coffee later on.

I don't really understand his either, it's weird, right, if people age (say a couple for example) and the guy gets bald and a beer gut and the woman gains a little weight (maybe due to childbearing/whatever) usually the woman is looked down upon more for her appearence. The guy just says screw it, and the girl usually tries to keep improving her apearence during the latter years of their life. This example kind of reminds me of my grandparents - my grandfather has had a beer belly for as long as I can remember, but my grandmother still likes to get dressed up and put on make up. And some of my friends grandparents are this way too, its funny. But to stop and think about it, it's like guys are just catching up to girls with the idea of keeping up our appearance to stay healthier in our latter years like you girls do. Look at the average ages of males and females and how long it takes both sexes to get ready for the day when they wake up, but girls however, are usually their own toughest critic on how their appearence is, or a lot more than guys are. And if somebody pokes fun at something that you may be even tougher on yourself about, it's going to hurt a lot more than if it was something you feel like you had little thought about in the first place. Then you would start to think about it, and now it has started to happen to guys too, it's just something that had more concern amongst girls before it did with guys. So now we got to catch up and get rid of the beer gut's.

I don't understand, either

personally find it equally unacceptable in both sexes to be fat.

I don't hate them per se. It is very rude to call them names, especially since they have enough problems to worry about. The nasty comments are just insult to injury (the "injury" being the health problems associated with obesity).

Because girls are thought to be prettier and are often valued solely for their physical appearance. Plus guys are just a lot more visually stimulated than we are. So the object of their attentions needs to be visually pleasing.

Although I have to admit I'm totally weird about this with guys. I don't think I could date a fat guy, and lots of my friends have been with guys that I consider to be gross just because of their weight. I'm pretty sure I'm atypical in this regard, though.

I think a lot of it has to do with the fact that girls tend to be more critical of their own bodies. We compare ourselves to and judge each other while men seem to be a lot more comfortable as they are. The media has obviously picked up on that, because you can't open a magazine or turn on the TV without hearing about workouts for the "perfect bikini body" or weight loss supplements--and they're almost always aimed toward women. That puts the idea into people's minds that women need to be thin, so everyone is more critical.

I don't think people consider it socially acceptable for men to be overweight though. I think it's put into boys' minds from a young age that being "fat" isn't a good thing, so being thin or having a little extra weight is acceptable for them. Meanwhile, women aren't just trying to be thin, they feel like they have to have the perfect curves in order to be more feminine and sexy.

Personally I think guys can carry a little extra weight better than women. When it comes to obesity I find that it is equally "not ok" for men and women. It is unfair that men can carry weight better but they are a different shape to women.

B/c society is used to skinny models in magazines and thin actresses on tv and in movies. They are used to seeing that. Guys just aren't like that. I don't understand this either.

seriously, I guess it is the difference in the make. girls somehow seem to be judged harshly on the parameters of weight, body shape, etc while guys seem to enjoy the benefits of not being judged so much on appearance.

I don't really understand it either, it's really unfair.
I mean, if you think about it, guys aren't judged as harshly as girls at all. It's accepted for them to be a bit overweight, hairy, and even average-looking.
Girls, however, are expected to be perfect, or to try to be :/