Foods That Cause Protein in Urine Protein in urine, also known as proteinuria, is an early sign that the kidneys are under stress or not filtering waste properly. Normally, kidneys filter toxins and retain essential nutrients like protein inside the blood. But when kidney function weakens due to diseases like diabetes, high blood pressure, or chronic infections, proteins start leaking into the urine. One of the major lifestyle factors that can worsen this condition is poor dietary habits. Certain foods can place extra burden on the kidneys and contribute to increased protein leakage.
