Diabetes and Dehydration: Signs and Causes


If you live with diabetes you know the importance of maintaining healthy blood sugar levels.

If this option is not checked, high blood sugar can damage the blood vessels and nerves in your body. It can also cause complications like kidney failure, blindness, and cardiovascular disease.

While medications, exercise, and a healthy diet can lower your blood sugar, staying hydrated is also important. High blood sugar can lower the levels of fluids in your body, which can lead to dehydration.

Dehydration and diabetes can go hand in hand. Thirst and dry mouth – both signs of mild dehydration – are often the first indicators of diabetes. But what is the connection between diabetes and dehydration?

This connection has everything to do with how the body reacts to high blood sugar.

Diabetes means that your body is not making insulin or is not using insulin properly. Insulin is a hormone that enables your body’s cells to absorb sugar in your bloodstream and then use that sugar for energy.

If your body doesn’t use insulin properly, sugar can build up in your bloodstream. When your blood sugar stays high for an extended period of time, your kidneys have to work harder to filter and remove the excess glucose. It does this through urination.

It is this increase in urination that leads to dehydration, especially if you don’t replace lost fluids.

Diabetes thirst

Excessive thirst is a first symptom of diabetes as well as a symptom of mild dehydration.

Diabetes thirst increases when your body loses too much water through urination caused by high blood sugar. Even if you drink often, you may still feel thirsty or dehydrated.

This is because your kidneys keep making more urine to flush out excess glucose. This cycle lasts as long as your blood sugar is too high.

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is a complication of diabetes that occurs after prolonged high blood sugar and is more common in type 1 diabetes.

When your cells cannot absorb sugar for energy, your body begins to burn fat for fuel. This process produces a type of acid called ketones, and having too many ketones in your bloodstream can lead to serious complications.

This condition can cause your body to lose a large amount of fluids, which can put you in a state of shock. Severe symptoms of diabetic ketoacidosis include:

  • dry skin
  • flushed face
  • a headache
  • Muscle stiffness
  • Vomit
  • diabetic coma

Diabetes insipidus

Diabetes insipidus is a completely different condition from diabetes mellitus and can either be due to the pituitary gland not producing vasopressin properly or the kidneys being unable to respond to it. Vasopressin is an antidiuretic hormone and it causes the kidneys to be unable to hold back water.

When this happens, your kidneys will pass a large amount of urine, which can lead to dehydration.

Keeping your blood sugar in a normal range helps your body maintain healthy fluid levels. But it also helps to stay hydrated. In addition to fighting dehydration, drinking water can help your body get rid of excess glucose.

If you live with diabetes, you should drink plenty of fluids – about 1.6 liters (L), or 6.5 cups a day for women; and 2 liters or 8.5 glasses a day for men.

While water is a great all-round drink and is highly recommended for increasing fluid intake and preventing dehydration, other drinks are also effective for dehydration.

Add a few dashes of fresh lime or lemon juice to add flavor to the plain water. You can also stay hydrated by drinking decaffeinated herbal teas, skimmed milk, and sugar-free coffee.

However, you should avoid energy drinks, fruit juices, and sodas. These drinks are high in sugar and can further increase your blood sugar. Sparkling water is fine as long as it’s sugar-free.

Also, keep in mind that with diabetes-related dehydration, it doesn’t always cause symptoms. Sometimes symptoms are not apparent until severe dehydration.

Common symptoms of mild dehydration include:

If you are severely dehydrated, you may experience low blood pressure, weak pulse, and confusion.

Some factors can make dehydration worse or increase your risk. This includes exposure to hot, humid weather and strenuous exercise. Dehydration can also worsen if you drink alcohol or beverages containing caffeine.

If you are showing signs of mild dehydration, drinking more water and treating your diabetes can help balance your fluid levels and improve hydration.

Nevertheless, if you cannot control your blood sugar with medication or lifestyle changes, see a doctor. Your doctor may need to adjust your diabetes medication.

You should also see a doctor if you have severe symptoms of dehydration, such as confusion, low blood pressure, and a weak pulse, or if you have symptoms of diabetic ketoacidosis. These symptoms include:

  • Nausea or vomiting
  • fruity smelling breath
  • shortness of breath
  • confusion

Also see a doctor if you have signs of dehydration but your blood sugar remains within a normal range.

Diabetes is a chronic condition that, if left untreated, can cause serious complications. Increased urination and thirst are signs of dehydration. It is important to take steps early to rehydrate your body and maintain healthy blood sugar levels.

If this option is not checked, dehydration can become life-threatening and increase the risk of kidney failure, seizures, and even coma.