In today's workplace, Pachter said, handshake behavior is no longer based on gender; it's based on rank and host/visitor status.

So even though the woman looks better, she steps on the scale, sees a number she doesn’t like and then gets discouraged.

It’s unfortunate that our culture is so weight-obsessed when the problem isn’t really weight itself, it’s fat. For most men, runway models are way too skinny to be considered an ideal body type.

But if you're worried about confusion arising when the bill comes, he said you should address the issue head-on when you accept the invitation.

"Set that expectation that you're going to share costs," he said.

(This study and others can be found in The Evolution of Desire by David M Buss) Now I am not saying go cancel your gym membership and eat a tub of ice cream on the couch.

Weight means your entire body weight – muscle, organs, fat, water, etc. Fit means that you have a low body fat percentage (for women, having a body fat percentage in the lower 20s is good).

"Just turn around and say, 'thank you.'" An important note: Both Pachter and Senning mentioned that what you do in your personal relationships is your own business.

You and your partner, or your friends, can figure out what feels right for you, whether that means having the man pay the bill or carry the packages.

There was a study I read in college about body weight and attractiveness in women.

They had hundreds of men look at pictures of women’s bodies and rate them according to which they found the most attractive.

Then, hundreds of women looked at these same pictures and rated how they than what the women believed to be the ideal weight that men want.