What Do Urine Tests Say About Diabetes?

Medically Reviewed by Michael Dansinger, MD on August 25, 2022
4 min read

When you have diabetes, you’re no stranger to tests that keep track of your disease. Most look at your blood, but there are others. Two simple ones that check your urine can help you and your doctor watch for kidney disease and severe high blood sugar.

About one-third of people with diabetes have problems with their kidneys. But early and tight control of your blood sugar and blood pressure, plus help from certain medications, can keep these organs working like they should

To check for problems, your doctor can do a test that measures the amount of protein in your urine, called microalbuminuria. It shows up when small amounts of albumin (the main protein in your blood) seep into your pee. Without treatment to slow the leak, your kidneys could be damaged and eventually fail.

You should get this test every year starting as soon as you’re diagnosed with type 2 diabetes. That’s because high blood sugar is usually present many years before you find out you have the disease.

If you have type 1 diabetes, you probably won’t get the test until you’ve been diagnosed for 5 years.

If the test is positive, your kidneys are leaking protein into your urine. This is a sign that your kidneys are not working as well as they should -- even if you feel fine and have no symptoms. Your doctor will suggest medications or lifestyle changes to help control these conditions:

  • Kidney damage. You may start specific medicines to prevent further harm. If your microalbumin level is high, your doctor may suggest another type of test that requires you to collect samples for 24 hours. This can better tell the extent of damage to the kidneys and see how well they’re working.
  • High blood sugar. Studies show tight control of your blood sugar can lower kidney damage, so your doctor may put you on more aggressive treatments.
  • Blood pressure. Lowering blood pressure reduces your risk of diabetes-related kidney damage. Get it checked each time you have an office visit. The recommended reading for most people with diabetes is less than 130/80.
  • Cholesterol. Since increases in microalbuminuria over time has been linked to heart disease risk, your doctor will work with you to keep your cholesterol and other fats in a healthy range.
  • Other factors that can increase the risk of kidney disease are being overweight or obese and smoking.

If you have type 1 diabetes, your doctor could ask you to check the urine for ketones. Your body makes them when it doesn’t have enough insulin and turns to fat stores to create energy for your cells. Ketones are toxic in large amounts. Too many of them can cause a life-threatening emergency condition called ketoacidosis.

Your doctor can check for ketone levels, or you can do it at home with an over-the-counter kit. You simply dip a test strip into your urine. It will change color, and you’ll compare it to a chart to see what your reading means.

If you have type 1 diabetes, you may need to check your urine for ketones if:

  • You feel sick (have a cold, the flu, or other illness) and have nausea or vomiting.
  • You’re pregnant.
  • Your blood sugar level is over 300 mg/dL.
  • You have symptoms of high blood sugar including extreme thirst or tiredness, a flushed or foggy feeling, or your breath smells fruity.
  • The doctor tells you to.

If you have type 2 diabetes, there isn’t much chance you’ll have too many ketones, even if you’re taking insulin. But it could happen during a severe illness. Your doctor may tell you to check your urine when:

  • You have a cold, the flu, or other illness or have unexplained nausea or vomiting.
  • Your blood sugar level is over 300 mg/dL and continues to rise throughout the day.

A urine test for ketones should always be negative. Report a positive result to your doctor immediately. You should also let them know right away if your blood sugar remains high or if you have stomach pain, nausea, vomiting, rapid breathing, sweet-smelling breath, or if you’re peeing a lot.

The doctor may tell you to:

  • Drink plenty of water and fluids to lower the amounts of ketones and stay hydrated.
  • Continue to check your blood sugar. If it’s high, you may need to give yourself a small amount of rapid-acting insulin.
  • Go to the local emergency room so you can get intravenous fluids and insulin.

Keep detailed records of any urine or ketone tests you perform. These can help alert you and your doctor to any problems. Bring them with you on every office visit.