A low urine specific gravity test indicates that the concentration of your urine is close to that of water. This is usually not a cause for concern and likely indicates that you are very hydrated.
Low specific gravity (1.001-1.003) may indicate the presence of diabetes insipidus, a disease caused by impaired functioning of antidiuretic hormone (ADH). Low SG also may occur in patients with glomerulonephritis, pyelonephritis, and other renal abnormalities. In these cases the kidney has lost its ability to concentrate due to tubular damage.Ideally, urine specific gravity results will fall between 1.002 and 1.030 if your kidneys are functioning normally.
To find out more, click here:
HealthMatters.io - Lab results explained 