So where exactly does uric acid come from? Uric acid is actually a metabolic waste product in the body, produced by the metabolism of something called “purine” (what is purine? We do not need to know, but it is a substance in the body, and it is indispensable). To put it bluntly, uric acid is the garbage in the human blood, which is not good for the body, so it should be excreted, keeping it is nothing to do. In general, most of the uric acid is excreted through the urine, and a small portion is excreted through the feces. This is the reason why many patients with poor kidney function have high uric acid.