Estimated BMI: 21

This "Bootylicious" songstress gets called curvy by the tabloids, but by BMI standards, she's perfectly proportioned. Our experts estimate that Beyonce is a svelte 130 lbs. At 5'6", that gives her an estimated BMI of 21—well within the "normal" range.

So if Beyonce's BMI is right on target, what about all the super-skinny celebs that make her seem shapely?