Kidney Disease and Diabetes: How Much Water Do You Need?

Diabetes and Hydration

Hydration plays a crucial role in managing diabetes, especially for individuals who also have chronic kidney disease (CKD). The connection between these two conditions is significant, as CKD affects approximately 10 to 40 percent of people with type 2 diabetes. This combination is often referred to as diabetic kidney disease. Managing both conditions requires careful attention to dietary and fluid intake, as each condition has its own set of recommendations.

Proper hydration is essential for maintaining balanced blood glucose levels. When the body is well-hydrated, it helps regulate blood sugar effectively. Conversely, dehydration can lead to more concentrated glucose levels, which may cause spikes in blood sugar. High blood glucose levels can further exacerbate dehydration due to increased urination and extreme thirst. This cycle highlights the importance of maintaining adequate fluid intake.

Illnesses such as acute diarrhea and vomiting can lead to severe dehydration, increasing the risk of complications like diabetic ketoacidosis (DKA). It's important to prioritize fluid intake when sick, and seek immediate medical attention if symptoms persist for several hours.

Dehydration can also harm the kidneys, as it hinders the delivery of nutrients necessary for their function. Therefore, staying properly hydrated may help reduce the risk of developing diabetic kidney disease.

Chronic Kidney Disease and Hydration

The kidneys play a vital role in regulating fluid balance in the body. They signal thirst when more water is needed and eliminate excess fluids through urine. As chronic kidney disease progresses, this balance becomes increasingly difficult to maintain.

In the early stages of kidney disease, proper hydration supports kidney function by helping to remove waste products from the body. However, as the disease advances, fluid intake may need to be limited to prevent fluid retention. Signs of fluid retention include swollen feet and ankles, breathlessness during minimal activity, and difficulty breathing while lying down. It's crucial to report these symptoms to a healthcare provider promptly.

For those on dialysis, fluid intake must be carefully managed based on the body's ability to produce urine. Dialysis involves filtering blood outside the body, and patients must adhere to strict fluid restrictions to avoid complications.

How Much Water Should You Drink?

There is no one-size-fits-all approach to fluid intake for individuals with diabetic kidney disease. Optimal hydration should be tailored to an individual’s clinical condition, including factors such as CKD stage, other medical conditions, and risk of fluid overload or low sodium levels.

Additional considerations include metabolism, insensible losses (water lost through skin and breathing), and environmental factors such as heat or humidity. For example, individuals living in hot climates may require more fluids due to increased sweating.

Drinking about 70 to 85 ounces (2 to 2.5 liters) of fluids per day, spaced throughout the day, is generally recommended. However, this may vary depending on blood sugar control and other health factors. If blood sugar is poorly controlled, additional fluids may be necessary to compensate for increased urine output.

For those with advanced kidney disease, fluid intake may need to be restricted to less than 1.5 liters per day to avoid complications like hyponatremia. However, healthcare professionals should adjust these recommendations based on individual needs and environmental conditions.

Fluid Options for People With CKD and Diabetes

Water is the safest option for hydration, but other fluids can also contribute to daily intake. These include:

• Ice
• Soups
• Stews
• Protein drinks
• Dairy and nondairy milk
• Frozen fruits

While these options offer variety, individuals with restricted fluid intake should exercise caution. In some cases, tracking total fluid intake, including soups and high-water-content foods, may be necessary, especially if there are electrolyte imbalances.

For those with advanced CKD, monitoring high-water-content foods and potassium-rich fruits and vegetables is important to prevent complications such as hyponatremia and high potassium levels.

Avoiding caffeinated, alcoholic, and sweetened beverages can further support healthy fluid levels.

Hydration and Your Medications

Medications can significantly impact fluid recommendations. For instance, SGLT2 inhibitors, used to manage both diabetes and CKD, can increase urine output and the risk of dehydration. Patients taking these medications should ensure they drink enough water to stay hydrated.

Diuretics, prescribed to manage fluid buildup, can also lead to dehydration if not monitored closely. It's essential to inform healthcare providers about any kidney issues when taking diuretics to receive personalized fluid recommendations.

Dehydration Warning Signs

Prompt medical attention is necessary if dehydration signs are present, including intense thirst, reduced urine output, dark urine, fatigue, dizziness, confusion, and skin that doesn’t flatten after pinching. Fluid overload can also occur, leading to swelling, nutritional deficiencies, high blood pressure, and breathing difficulties.

The Takeaway

Managing hydration with diabetic kidney disease is complex and requires close collaboration with a healthcare team. Fluid needs vary widely and depend on factors such as CKD stage, other medical conditions, and medication use. Tailoring daily fluid intake to individual needs is essential for optimal health outcomes.

Resources We Trust

• Cleveland Clinic: How to Keep Your Kidneys Healthy
• National Kidney Foundation: Healthy Hydration for Your Kidneys
• American Diabetes Association: Why You Should Drink More Water
• Harvard Health Publishing: Caring for Your Kidneys
• American Kidney Fund: Fluids

Editorial Sources

Everyday Health follows strict sourcing guidelines to ensure content accuracy. Sources include peer-reviewed studies, board-certified medical experts, patient experiences, and top institutions.

Sources

• Diabetes - A Major Risk Factor for Kidney Disease. National Kidney Foundation.
• Healthy Hydration and Your Kidneys. National Kidney Foundation.
• 10 Surprising Things That Can Spike Your Blood Sugar. Centers for Disease Control and Prevention.
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• Diabetes Symptoms: When Diabetes Symptoms Are a Concern. Mayo Clinic.
• June 27, 2023.
• Ooi E et al. Clinical and Biochemical Profile of 786 Sequential Episodes of Diabetic Ketoacidosis in Adults With Type 1 and Type 2 Diabetes Mellitus. BMJ Open Diabetes Research and Care.
• December 8, 2021.
• Managing Sick Days. Centers for Disease Control and Prevention.
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• He Y et al. Association between hydration status and the risk and all-cause mortality of diabetic kidney disease. Renal Failure.
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• Fluids. American Kidney Fund.
• Why hydration is important for kidney health. Kidney Research UK.
• Dialysis. Cleveland Clinic.
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• Empagliflozin. MedlinePlus.
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• Diuretics. Cleveland Clinic.
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• Dehydration. Mayo Clinic.
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Meet Our Experts

Igor Kagan, MD
Medical Reviewer
Castle Connolly Top Doctor
Igor Kagan, MD, is an assistant clinical professor at UCLA. He spends most of his time seeing patients in various settings, including outpatient clinics, inpatient rounds, and dialysis units. He is also the associate program director for the General Nephrology Fellowship and teaches medical students, residents, and fellows. His clinical interests include general nephrology, chronic kidney disease, dialysis, hypertension, and glomerulonephritis. He is also interested in electronic medical record optimization and serves as a physician informaticist.

Adam Felman
Author
Adam is a freelance writer and editor based in Sussex, England. He loves creating content that helps people and animals feel better. His credits include Medical News Today, Greatist, ZOE, MyLifeforce, and Rover, and he also spent a stint as senior updates editor for Screen Rant.

As a hearing aid user and hearing loss advocate, Adam greatly values content that illuminates invisible disabilities. (He's also a music producer and loves the opportunity to explore the junction at which hearing loss and music collide head-on.)

In his spare time, Adam enjoys running along Worthing seafront, hanging out with his rescue dog, Maggie, and performing loop artistry for disgruntled-looking rooms of 10 people or less.