Protein in urine, also called proteinuria, occurs when the kidneys allow proteins, such as albumin, to leak into the urine. Normally, the kidneys act as a filter, retaining necessary proteins in the bloodstream while removing waste and excess fluids. In healthy individuals, only trace amounts of protein are present in urine, often undetectable by standard tests.
When protein levels in urine are elevated, it may indicate kidney dysfunction, high blood pressure, or other conditions affecting the filtration process. Protein in urine is an important biomarker for evaluating kidney health and overall bodily function.