My parents used to get it when I was growing up, back in the 1940s. As I recall, it's primary claim to fame was pictures of half-naked women from Africa and Asia. I don't think it ever was scientifically grounded.
Well they did have the cover of the Afghan Girl. That was the high point of their existence.
My parents subscribed to it and through the ‘60s and ‘70s it was a great source of scientific articles.