Can. The kidneys are responsible for the production of bone marrow. The kidneys correspond to the bladder among the six internal organs. The ear is the opening hole. Avoid salt. In addition, the corresponding Five Emotions are fear, which means that fear injures the Kidneys. The corresponding season is winter. This means that winter is the best season to nourish the kidneys. The five colors corresponding to the kidneys are black. Therefore, the black food has the effect of tonifying the kidneys. Like you said, black beans are a kind of, in addition to black rice, black sesame, black fungus, black jujube, He Shouwu, mulberry, goji berries, walnuts, kelp, leeks, garlic, nori, plums, grapefruit, antlers, eucommia, fennel, and so on.