Signs and Symptoms of Type 2 Diabetes

by LAURIE MARBAS, M.D.  Last Updated: Feb 22, 2016

Type 2 diabetes is usually asymptomatic at diagnosis. Type 2 diabetes is the most common type of diabetes and is caused by elevated blood glucose levels, decreased insulin production and/or insulin resistance. Most Type 2 diabetics do not have signs of the disease, but rather it is discovered on routine laboratory results. For example, an individual would have an elevated glucose result, and this would prompt further evaluation to determine if Type 2 diabetes was present.

Classic Symptoms of Type 2 Diabetes

Even though most individuals are asymptomatic at diagnosis, there are some classic symptoms to be aware of, and medical attention should be sought if any of these symptoms are occurring:

1) Increased urination (polyuria) occurs when blood glucose levels in the urine are greater than 180 mg/dL, which is the kidney’s glucose threshold. This excess of sugar in the urine (a condition known as glycosuria) can be assessed by taking a urinalysis.

2) The increased urine glucose causes increased urination through osmotic diuresis. Osmotic diuresis is increased urine amount due to certain substances being present in the filtering component of the kidney. When a substance, such as glucose, cannot be reabsorbed in the kidney, an increased amount of fluid is pulled into the kidney leading to increased urination.

3) The increased urination can lead to a state called hypovolemia, which is a low volume of fluid inside the body, otherwise known as dehydration.

4) When a person is dehydrated he has increased thirst. If an individual attempts to replenish his fluid loss with ingestion of fluids that have a high concentration of sugar (such as sodas), the situation is dramatically worsened, increasing the urination and fluid loss even further.

5) Nocturia, or increased urination at night, may also be present.

6) Blurred vision can occur due to the elevated glucose concentration in the blood.

7) Occasionally, weight loss will occur in some individuals, especially if they cannot produce much insulin. When the body does not have enough insulin to drive glucose into cells for energy, it will begin to break down fat and protein. This causes rapid weight loss, but it’s typically temporary. Weight gain will occur after the diabetes is properly treated.