Wikipedia says, "He worked as a herbalist, selling lingzhi, goji berry, wild ginseng, he shou wu and gotu kola along with other Chinese herbs, and lived off a diet of these herbs and rice wine."
If this really was what he ate, it's a pretty well-balanced, tonifying diet. The lingzhi would benefit the immune system, the goji berry (gou qi zi) and he shou wu would tonify liver blood and kidney essence, and the ginseng (probably Panax ginseng), would tonify Qi. I really wonder what the "other Chinese herbs" were.