According to Ernst Wilhelm:
“ALL planets represent necessary functions, only when they are bad to they indicate problems. Saturn’s job is to keep the body clean so that it does not get sick. If his ability to do this is weak, then the body gets a disease. So the stronger Saturn the less chance of disease and the longer the longevity. Then, if Saturn is joined a planet in cleaning the body the part that all the toxis get stuck in are the organ of the planet he is with. Of if he aspects a planet he is an enemy to he will dump toxins there too. But it is not that he is causing the disease, just that the toxins are too much and he has to put them somewhere and so then disease sets in.”
This is a very nice explanation of how Saturn can work in Vedic Astrology.