# Nutrition with Kidney Failure and Dialysis
Fluid intake
In kidney failure, the kidneys can no longer properly excrete fluid. This fluid excess can accumulate in the body, leading to swelling, breathing problems, and extra strain on the heart. Dialysis removes fluid excess, but between treatments fluid can accumulate again.
Many people on dialysis are told they need to limit their fluid intake. This is not arbitrary advice, but a necessary precaution. The amount depends on how much urine someone still produces and how well the dialysis works. This differs per person and changes over time.
ProveniIncluded in official guidelines, or approved by EMA or FDA
Fluid restriction helps prevent or reduce irregular heartbeats, high blood pressure, and lung congestion. Regular monitoring of body weight between dialysis sessions provides insight into fluid accumulation.
Fluid restriction requires creativity: using small cups, addressing dry mouth with syrups or ice, and understanding which foods contain a lot of fluid (soup, fruit, yogurt). This is not easy and requires practice. A dietitian can help with practical tips.
Proteins
The kidneys excrete protein breakdown products. With dialysis, proteins are also lost. This risk of protein loss and muscle weakening is an important concern.
At the same time, people with kidney failure should not eat too much protein-rich food, because protein breakdown produces toxic substances (such as urea and creatinine), which dialysis must handle. This is a difficult balancing act: enough protein for muscle strength, not so much that it overburdens the dialysis work.
ProveniIncluded in official guidelines, or approved by EMA or FDA
Adequate protein (though less than for healthy people) helps maintain muscle mass and prevent malnutrition. This is especially important because people with kidney failure more quickly experience eating problems, nausea, and muscle loss.
Recent research (*The Challenges of Establishing an Optimal Link Between Nutritional Requirements, Dietary Knowledge and Culinary Skills in Chronic Kidney Disease*, 2026) emphasizes that many patients do not know well which foods are suitable, and that the gap between nutritional advice and practical cooking can be large. This is not something to feel guilty about — this is a systemic issue.
Some dialysis patients have amino acids added to their dialysis fluid, especially with peritoneal dialysis.
ResearchediPositive results in clinical studies, not yet standard treatment
This can help compensate for protein loss, but the benefits and best way of application are still being researched.
Electrolytes (sodium, potassium, phosphorus)
The kidneys regulate salt balance. In kidney failure, sodium can accumulate, which worsens thirst and fluid retention. This makes salt restriction important.
ProveniIncluded in official guidelines, or approved by EMA or FDA
A low salt intake helps keep blood pressure stable and reduces thirst, which in turn reduces fluid intake.
Potassium and phosphorus are two electrolytes that receive a lot of attention. A sick pair of kidneys cannot excrete potassium well, causing it to accumulate in the blood. Too much potassium can disturb heart rhythms. Dialysis removes potassium, but it builds up quickly again, especially through diet.
ProveniIncluded in official guidelines, or approved by EMA or FDA
Low-potassium eating (less potatoes, bananas, nuts, chocolate, dried fruit) helps keep potassium levels balanced. This varies depending on how much urine a person still produces and how well their dialysis works.
Phosphorus binds together with calcium in the blood. Too much phosphorus leads to bone deterioration and hardening of tissues around the heart. Phosphorus is found a lot in milk, cheese, meat, and whole-grain products. This is difficult because much of it sounds healthy.
ProveniIncluded in official guidelines, or approved by EMA or FDA
Lower phosphorus intake helps prevent bone and vessel loss. Many dialysis patients also receive medications (binders) that trap phosphorus in the stomach so it is not absorbed. This makes diet alone not enough.
Vitamins and minerals
With dialysis, many vitamins are lost, especially the water-soluble ones (B vitamins and vitamin C).
ProveniIncluded in official guidelines, or approved by EMA or FDA
Dialysis patients usually receive additional vitamins. This is not something for self-care — the dosage and type depend on blood and nutritional status.
Vitamin D plays a role in bone strength and calcium absorption. In kidney failure, the body cannot activate vitamin D properly.
ProveniIncluded in official guidelines, or approved by EMA or FDA
This is one reason why many dialysis patients are prescribed vitamin D replacement or stronger forms.
Iron can be lost through blood loss via the dialysis machine.
ProveniIncluded in official guidelines, or approved by EMA or FDA
Anemia is frequent in kidney failure; iron supplementation helps combat this, but this is medication, not nutrition.
Calcium and magnesium: also difficult to keep in balance. Too much or too little calcium leads to bone problems. This is part of medication and dialysate, not nutrition alone.
Self-management and nutritional knowledge
Recent research (*Renal nutrition knowledge among haemodialysis patients*, 2026) shows that many dialysis patients lack sufficient knowledge of their dietary restrictions and make many mistakes. This is not unusual: nutrition for kidney failure is complicated, sometimes contradictory, and difficult to manage alongside work, family and taste.
ResearchediPositive results in clinical studies, not yet standard treatment
Better nutritional education and practical support (for example, cooking together, cards with food choices) help people eat more safely and strongly.
Therapy adherence (adherence to nutrition, medication and dialysis) is strongly linked to how someone experiences themselves and whether they feel supported.
ResearchediPositive results in clinical studies, not yet standard treatment
Fear of deterioration and feelings of guilt can worsen dietary choices, while self-compassion and support can help.
Nutrition and different dialysis methods
**Hemodialysis** (usually 3–4 times per week, a few hours per session): here blood is purified via a machine. More electrolytes and water are lost. This places strict demands on nutrition between treatments.
**Peritoneal dialysis** (peritoneal lining is used; more frequent, at home): here fluid excess diffuses through the abdominal wall. Patients lose more protein, so protein is somewhat less restricted here. Dialysate contains glucose, which is partially absorbed, so nutrition here also depends on the type and number of exchanges per day.
ResearchediPositive results in clinical studies, not yet standard treatment
Protein-containing dialysates (amino acid-based) are being investigated to prevent protein loss in peritoneal dialysis.
The dialysis schedule, body weight and kidney function together determine what someone is allowed and must eat. This is not the same for everyone.
When is someone undernourished or overfed?
Undernutrition is frequent and harmful in kidney failure: it leads to muscle loss, less resistance to infection and slower healing. But it is subtle — weight alone does not tell the whole story.
Severe obesity can further deteriorate kidney function (the case of anabolic steroids combined with high protein intake shows how extreme nutrition can harm).
A dietitian assesses together with your healthcare provider via blood values, weight trend and body composition whether nutrition is on track.
Summary
Nutrition for kidney failure and dialysis is not a one-size-fits-all recipe. It requires:
- understanding of fluid intake, salt, protein, potassium, phosphorus and vitamins
- adjustments depending on the dialysis method
- regular monitoring via blood values
- practical support and patience
A dietitian with experience in kidney failure is a valuable partner. Self-care helps, but dialysis patients do not always feel at home with the rules — this is normal and not a shortcoming.
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_This information never replaces a doctor's judgment. Always discuss your situation with your own healthcare provider._