No daily fluid intake recommendations apply to everyone with diabetic kidney disease. “Optimal water intake should be individualized, based on clinical assessment and risk factors rather than a universally recommended amount,” says Abbal Koirala, MBBS, an assistant professor of medicine at Johns Hopkins University in Baltimore. “Both excessive and insufficient water intake may be harmful, and the ideal range depends on a person’s CKD stage, other medical conditions they may have such as heart failure, and their risk of fluid overload or low sodium in the blood, also known as hyponatremia.”
Boonphiphop Boonpheng, MD, a clinical assistant professor of medicine at University Hospitals in Ohio, suggests considering additional factors when determining ideal fluid intake:
- A person’s metabolism
- Insensible losses (the tiny but constant loss of water through the skin and during exhalation)
- The impact of fever, sweating, or exercise, especially in those who live in a hot or humid climates
- Diarrhea
Dr. Boonpheng highlights other considerations that can make water recommendations with CKD and diabetes complex. “In advanced kidney disease or for those on dialysis, you might need to restrict water intake to prevent low sodium levels in the blood,” says Boonpheng. “However, if you have a history of kidney stones, higher fluid intake helps prevent recurrence. Aim for about 70 to 85 ounces (roughly 2 to 2.5 liters) of fluids per day, spaced throughout the day, and try sipping some water after supper. If your blood sugar is poorly controlled — above 180 mg/dL — your kidneys excrete extra sugar through urine, which causes additional water loss. You may need to drink more to keep up.”
Hydration considerations may be even more complicated for people with advanced kidney disease. “People with stage 4 or 5 CKD often receive the advice to limit fluid intake to less than 1.5 liters per day to avoid hyponatremia, but a healthcare professional should adjust this for hot climates or increased insensible losses,” says Dr. Koirala. If you don’t have low sodium, Koirala recommends drinking water if you’re thirsty.
Fluid Options for People With CKD and Diabetes
- Ice
- Soups
- Stews
- Protein drinks
- Dairy and nondairy milk
- Frozen fruits
While these options provide a sense of variety, extra caution may be necessary for some people adhering to restricted fluid intake. “In most cases, people with CKD and type 2 diabetes don’t need to track foods with high water content closely,” says Boonpheng. “The exception is when there are other electrolyte problems, such as low sodium levels in the blood. In those cases, it may be helpful to track total fluid intake, including soups, fruits, and other foods high in water.”
Koirala recommends that people with advanced CKD track their consumption of foods with high water content. “These can contribute to water retention in advanced CKD, leading to hyponatremia,” he says. He also suggests keeping an eye on fruit and vegetable intake due to their potentially high potassium content, which can increase the risk of high potassium levels in people with advanced CKD. Many people with advanced CKD need to restrict their potassium intake.