Although most people don't have to think twice before popping the top on a can of soda, this beverage presents several problems for patients with advanced kidney disease. What type of soda is safe to drink and how much soda can be safely consumed are very real issues for these patients. Because kidney disease affects one in nine Americans, problems relating to soda consumption are widespread.
Liquid
As kidney function declines, many patients become less able to produce urine. Because they are less able to excrete fluids, any fluid that is consumed is retained. Dialysis is necessary to filter the blood and remove excess liquids.
Patients who have limited ability to make urine are instructed to limit their fluid intake. Nephrologists tell patients how much liquid is safe for them to consume between dialysis sessions. Because soda is a liquid, the patients will have to measure how much they consume and make sure that it fits in their total fluid allowance.
Liquid Overload
If you drink so much soda that it exceeds your total fluid allowance, the extra fluid increases the pressure inside your veins and arteries. This increased blood pressure is particularly dangerous because cardiovascular disease is the leading cause of death for patients with limited kidney function. Davita, a leading dialysis provider, reports that excess fluids cause "swelling of feet and legs, shortness of breath, additional strain on the heart, heart failure and fatigue."
Phosphorus
Some sodas, such as colas, are also high in phosphorus. Although consuming excess phosphorus is not an issue for people with normal kidney function, it is a problem for people with advanced kidney disease. Healthy kidneys automatically regulate phosphorus levels in the blood. Diseased kidneys are less able to perform this function, so phosphorus levels can become dangerously high if the patient drinks too much of the wrong kinds of soda.
Consequences
If the patient consumes too much high-phosphorus soda, the excess phosphorus starts to leach calcium from the bones, which weakens them and causes osteoporosis. Calcium that gets leached out goes into the bloodstream. The National Kidney Foundation reports this leads to "dangerous calcium deposits in blood vessels, lungs, eyes, and heart."
References
- Davita: Food That Counts as Fluid on the Kidney Diet
- Davita; Phosphorus and Chronic Kidney Disease; Helen Dorrough
- National Kidney Foundation: Phosphorus and Your CKD Diet
- American Association of Kidney Patients; What to Watch: Fluid and Dietary Intake for Hemodialysis Patients; Lori Hegel; January 2002
