Eggplant is generally not bad for kidneys and is good for the body. However, it may not be suitable for certain people. Eggplants contain oxalates and although they are not as many as they are in other fruits and vegetables, nevertheless, oxalates can improve the formation of kidney stones in some people,e, and kidney stones, if not treated, can lead to kidney death or other kidney injuries. Hence, people who are prone to kidney stones should stay away from eggplant or any oxalates producing fruits and vegetables.