Diseases are from three things

Three are they the causes of destruction for humans,
And call the healthy to diseases.
Alcoholism, too much lovemaking,
and eating food upon food.

The Imam was an accomplished doctor as well as a Jurist, and he was often mistaken as a doctor by other doctors who were always very impressed by his deep knowledge of the human body.
His advices of giving up alcohol and not overeating are easily acceptable and have vast amounts of medical research to back them up. As for his advice about too much lovemaking, there are different medical and psychological opinions on the matter, and the advice varies from person to person. But by and large, if lovemaking overtakes other more important things in ones life then this can clearly be from the "causes of destruction for humans". Medically the opinions are more murky but once again there is evidence to suggest that one can do more harm than good by over-stretching oneself.