|Water retention is also known by its more medical term, edema. This is a condition that results when water leaks into the body tissues from the blood. In normal circumstances, the fluid is drained from the body tissues through the lymphatic system – a network of tubes throughout the body that removes waste and extraneous material, and empties it back into the bloodstream.
Water retention problems arise when fluid is not removed by the lymph system properly; it is retained in the body tissues where it causes swelling (edema). Water retention in the body is most common in the feet and legs, but it can occur in the hands, arms, abdominal cavity (ascites) and around the lungs (known as pulmonary edema).