General dietary restrictions
Even before dialysis begins, a patient with kidney failure often faces dietary restrictions. In this phase, doctors often recommend a high drinking quantity as well as a low-protein diet. The recommendations for patients on permanent dialysis are often the exact opposite: what is needed now is a diet high in protein and a limited fluid intake.
For acutely ill patients, for whom dialysis is only performed for a limited period of time, slightly different recommendations apply than for chronically ill patients.
High-protein diet
Sufficient energy intake (2250 to 2625 kcal per day at 75 kg body weight) can also counteract increased protein breakdown. For acutely ill dialysis patients, physicians recommend an energy intake similar to that of intensive care patients (approx. 1,500 to 1,875 kcal daily at 75 kg body weight).
Low phosphate diet
Kidney weakness causes phosphate levels in the blood to rise. In the long term, this hyperphosphatemia leads to bone changes, vascular damage and hyperfunction of the parathyroid glands. Dialysis patients should therefore consume as little phosphate as possible. The problem is that phosphate intake is closely related to protein intake.
Dialysis patients should avoid foods that are particularly rich in phosphates. These include nuts, muesli, offal, egg yolks, legumes and wholemeal bread. Foods in which phosphate is added due to production are also more likely to be off limits. Examples include processed cheese, cooked cheese, canned milk and some types of sausage. You may want to ask the butcher’s shop about the phosphate content when purchasing sausage products.
Acutely ill or malnourished patients can also develop a phosphate deficiency. In this case, the missing phosphate must be replaced.
Low potassium diet
A low-potassium diet is not usually necessary for acutely ill patients.
Food selection
The following foods are particularly high in potassium and should be avoided during dialysis treatment:
- Nuts,
- Cereals, oatmeal,
- Dried fruit,
- vegetable and fruit juices, bananas, apricots,
- potatoes or vegetables that have not been properly prepared,
- fresh or dried mushrooms,
- Ready-to-eat potato products (mashed potatoes, potato dumplings, potato chips).
Dialysis patients should expressly avoid so-called dietary salts, which often contain very high amounts of potassium.
Food preparation
Low-salt diet
Dialysis patients often need to limit their salt intake. Table salt is the chemical compound sodium chloride (NaCl). Increased saline in the blood leads to increased blood pressure, accumulation of excess fluid in tissues and an increased feeling of thirst. If dialysis patients subsequently increase the amount they drink, overhydration can occur.
Also avoid highly salted foods during dialysis treatment. This includes pretzel sticks, pretzels, pickled cucumbers, smoked and salted meat and fish products (raw ham, sausage, anchovies, salted herrings, etc.), convenience foods, instant soups, stock cubes, instant sauces and ketchup.
Fluid intake and drinking quantity during dialysis therapy
Since regular determination of urine volume is cumbersome, dialysis patients should monitor their own weight gain by weighing themselves daily. Daily weight gain should not exceed 0.5 to 1 kilogram. Between two dialyses, patients should not gain more than two to three kilograms.
To help manage the feeling of thirst with limited fluid intake, the following tips will help:
- Avoid salty foods! Season instead of salting.
- Avoid sweet drinks.
- Take medications with food (cut down on drinking).
- Suck small ice cubes or lemon pieces.
- Chew gum without sugar or suck acid drops.
Diet for peritoneal dialysis (diaphragm dialysis)
- the amount of drinking,
- the consumption of fruits and vegetables, and
- the intake of foods containing phosphates.
