Answer to Steven's question on colors

Black color of course indicates kidney problems, but bluish not really. As a matter of fact, bluish color often tells stagnation of blood. So, it could be involved with different organs.

For sure the green color is the sign for liver, but please don't think the green color is exactly the one of the leaves of trees or plants, it's rather the color of our vessels, so sometimes it could be a bit bluish, right?

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