Under normal circumstances, the surface tension of urine is relatively low, basically does not produce foam. If there is foamy urine, it means that the urine contains substances that raise the surface tension of the urine, such as organic proteins, etc., and the cause should be found in time. For example, liver and kidney damage, proteinuria or urinary occult blood and other conditions will appear proteinuria, often a large number of bubbles in the urine and long-lasting situation, indicating that it contains protein. In addition, also includes diabetes mellitus urine sugar and urine ketone bodies, urine surface tension increases will appear foamy urine. In addition, when there is a urinary tract infection, the presence of bacteria in the urine will also produce foamy urine.