As interesting as Venus-gate is, I don't think art from the paleolithic really tells us much about the health of the average person. Think of some famous artwork from our era, imagine there is a nuclear disaster and everything is destroyed except that piece of artwork. What incorrect conclusions would a society come to if they just had that piece of artwork? Humans have an incredible ability to see things in nothing. Like this "time traveler" discovered in an old photo.
But Venus isn't the only victim. Particularly since remember here there is no evidence that the Venus of Willendorf was a portrait of a person. It's not an n=1 situation, it's an n=0 situation. There is no way to prove that someone would have had to have been familiar with excess adiposity in order to create a figurine like that and certainly nothing you can draw from that single figurine that would suggest we should eat a low fat diet!
Another great example of grasping at straws to use art in paleopathology (the study of disease in archeological remains, though this is obviously stupid here since there ARE no remains, just random statues) is Male Genital Representation in Paleolithic Art: Erection and Circumcision Before History.
In this paper the authors suggest that various features of phallic figurines from the paleolithic suggest all sorts of pathologies such as phimosis. Furthermore, the authors saw that they show circumcision was practiced, though he admits reluctantly it they could also be retracted penises. There is a reason this isn't in the Journal of Physical Anthropology, but in Urology instead. Here is some of the diagnostic "evidence"
Why are the weird phallic pieces proof of phimosis but the drawings with giant phalli not proof that people back then had abnormally ginormous penises? Why would you assume any sort of anatomical correctness for these sort of things? Just because you didn't put a foreskin in your art doesn't mean they didn't have them. I can report that in bars in Europe where few men are circumcised, when people draw penises in the bathroom (co-ed bathrooms are rather unpleasant BTW), they look like those in Figure 5.
So yeah, using art to muse about what people were like back then is interesting. Using it to diagnose illness or make inferences about the population is just silly.
Edit: is it true that circumcision is practiced by at least 7 forager groups. Interesting.