Ahem - Kristen, be careful with the hyperlinks! This is scientific and all - but you know some people.....
Watching a curvaceous woman can feel like a reward in the brain of men, much as drinking alcohol or taking drugs might, research now reveals.
...researchers had 14 men, average age 25, rate how attractive they found pictures of the naked derrieres of seven women before and after cosmetic surgery that gave them more shapely hips. These operations did not reduce weight but just redistributed it, by implanting fat harvested from the waists into the buttocks.
Brain scans of the men revealed that seeing post-surgery women activated parts of the brain linked with rewards, including regions associated with responses to drugs and alcohol.
...
Shapely hips in women are linked with fertility and overall health. As such, it makes sense evolutionarily speaking that studies across cultures have shown men typically find hourglass figures sexy.
Skippy - you may want to investigate here.
Hat tip Mrs. Salamander.