|  | Conditions Treatments | Kidney Disease

What Are the Causes of Low Specific Gravity?

Specific gravity measures the density of a substance in relationship to the density of water. Water is assigned a density of 1. Some materials, like rocks, have a fixed specific gravity while other substances, like human urine, fluctuate. Urine specific gravity measures the concentration of particles, with a normal reading falling between 1.020 and 1.028. Fewer particles lower the reading. Different factors can lead to a low specific gravity.

  1. Excessive Fluid Intake

    • Drinking water regulates specific gravity.

      Drinking more water than you normally do will cause your urine's specific gravity to decrease, while drinking less water causes the specific gravity to increase. Prior to a urine test, or urinalysis, it is important not to drink more or less water than normal. Otherwise, the reading may not be indicative of your true health. The color of urine indicates the concentration of particles. According to WebMD, the lightness or darkness of urine indicates the amount of water consumed. Drink enough water and you will have clear urine and a lower specific gravity.

    Diabetes Insipidus

    • Diabetes insipidus, known as "water diabetes" or DI, has some of the symptoms of diabetes, like increased urine and thirst, but differs in its causes. According to The Diabetes Insipidus Foundation, Inc., four different types exist. All cause a low specific gravity due to increased water in the urine. Vasopressin is a hormone secreted by the pituitary gland that prompts the kidneys to produce less urine as a means of increasing concentration. In Pituitary DI, the hormone is not produced, causing constant thirst and urination. The cure is an artificial hormone that replaces vasopressin. Gestational DI refers to the same condition during pregnancy. A third type, Nephrogenic DI, occurs when the kidneys fail to respond to vasopressin. Dipsogenic DI results from a failure in the brain to regulate thirst. No matter how much water a person drinks, he is always thirsty and eventually may suffer from water intoxication, or too much water in the body.

    Kidney Infection

    • Kidney infection, or pyelonephritis, also results in a low specific gravity. It can be caused by bacteria from the bladder that has spread to the kidneys. According to the National Kidney and Urologic Diseases Information Clearinghouse, other causes include kidney stones, enlarged prostate and defects in the urinary tract. Bacterial infection is treated with antibiotics. Symptoms include frequent painful or burning urination, fever, nausea and back pain. Kidney infections, if untreated, can lead to kidney failure.

    Diuretics

    • A diuretic is any substance that causes the body to remove water. Diuretics increase urine flow. According to WebMD, diuretics such as caffeine and alcohol can lower specific gravity. Diuretic medicines are used to reduce swellling from conditions such as hypertension.

Kidney Disease - Related Articles