Many metabolic wastes of the normal human body are excreted by the kidneys, such as creatinine, urea, uric acid and trace amounts of protein, so the tension of urine performance changes, and foam will appear. normal urine can have foam, which is nothing to worry about, and this foam does not last long, and can dissipate on its own after a few minutes of resting. But if there is a significant increase in the foam in the urine, foam like laundry detergent or beer foam, we should be alert to kidney disease, common causes are glomerulonephritis, nephrotic syndrome, diabetic nephropathy, iga nephropathy, lupus nephritis, etc., resulting in positive urine protein, there will be a lot of foam, you need to go to the hospital to check the urine routine, screening for kidney disease. If there is urine protein +, it indicates kidney damage, and you need to clarify the cause and treat it symptomatically to prevent further kidney damage.