well, season 1 really didn't have any supernatural elements.
It's maybe a bit trickier with season 2 (which I sometimes like to consider as a different series altogether), but the physical prowess of the familiars is explained as a product of selective breeding through the ages. Still well in the realm of science (or pseudo-science), I would think. S2 also has a brainy guy who's able to predict the future, but it's supposed to be statistical analysys and probabilities calculations. It's been a while since I've seen S2 but I don't recall straight-forward supernatural elements.
As for pseudo-science: yes, most of it, obviously.