Nutritional considerations for kidney dialysis patients

General rules

Hemodialysis is a method of treating patients with end-stage chronic renal failure , the essence of which is the use of hardware methods to cleanse the patient's body of toxic substances and normalize the water-salt balance (programmed hemodialysis / peritoneal dialysis ). Unfortunately, regular hemodialysis does not fully replace renal function, which contributes to the persistence of a number of metabolic characteristic of patients with chronic renal failure.
In addition, dialysis has side effects that lead to the loss of a number of food nutrients and the development of protein-energy malnutrition. Therefore, the condition of patients who are on hemodialysis is largely determined by proper diet therapy. The diet of such patients depends on a number of factors: the frequency/duration of procedures, the degree and nature of metabolic changes, the characteristics of dialysis solutions and the presence/severity of complications. Thus, nutrition during hemodialysis is a dynamic concept that requires individual selection of diet.

In addition to maintaining the necessary nutritional status of the patient, therapeutic nutrition is aimed at slowing the development of cardiovascular diseases and cerebrovascular changes, preventing mineral-bone disorders and correcting metabolic disorders resulting from uremic intoxication, and often inadequate kidney dialysis. At the same time, despite the need for an individual approach to the nutrition of patients undergoing regular hemodialysis, there are general principles of nutrition, which are presented below.

The diet for kidney hemodialysis is based on treatment table No. 7 G according to Pevzner, which in a number of ways differs from therapeutic nutrition in the pre-hemodialysis period. The diet is aimed at a balanced supply of food macro/micronutrients, taking into account individual metabolic characteristics and relieving the side effects of hemodialysis.

The diet provides for an increase in protein consumption to a level of 1.0-1.2 g/kg body weight/day (60-75 g), which is caused by protein losses during the hemodialysis procedure, a deterioration in its digestion and an increase in the rate of its breakdown. It is with this amount of protein consumption that the level of albumin and a positive/neutral nitrogen balance is maintained. However, protein consumption at this level does not induce uremic intoxication.

Insufficient protein content in the diet contributes to the development of protein-energy malnutrition (decrease in body weight index, levels of prealbumin , albumin , cholesterol ) and increases the risk of death. Excessive protein content in the diet contributes to an increase in nitrogenous waste in the blood and the development of uremia. Protein should be predominantly of animal origin, the source of which can be dietary red meat, rabbit, poultry, moderately fatty fish, chicken eggs, cottage cheese, milk and fermented milk drinks.

The energy value of the daily diet is calculated from the ratio of 35-40 kcal/kg/day (2800-2900 kcal/day). At the same time, a neutral energy balance is achieved with a consumption of 35 kcal/kg/day. Elderly people or those on bed rest are allowed to reduce the energy value of the diet to 2400-2500 Kcal/day.

The content of fats and carbohydrates in the diet must correspond to the physiological nutritional standards of a particular patient and provide the necessary energy value of the diet. On average, 100-110 g of fat and 400-450 g of carbohydrates per day. However, given the frequent disorders of lipid metabolism, the diet of such patients should not be overloaded with fats rich in cholesterol and saturated fatty acids.

It is advisable to include in the diet various vegetable oils and fish oils, which are sources of polyunsaturated fatty acids. In case of poor appetite and signs of hypoglycemia , it is permissible to increase the content of easily digestible carbohydrates in the diet (confectionery, honey, jam, jelly, mousses). However, if you have diabetes , carbohydrates in the diet are limited.

The content of table salt and free liquid has a special place in the diet of hemodialysis patients. Their quantity is determined individually depending on the level of blood pressure and the degree of water retention in the body. During hemodialysis, as a rule, the amount of urine excreted continuously decreases, which leads to sodium retention in the body, and even a slight increase in its consumption increases thirst and increases the consumption of free fluid, which contributes to the development of arterial hypertension and edema .

In addition, excessive salt consumption in hemodialysis patients leads to an increase in body weight in the period between hemodialysis sessions, myocardial hypertrophy, and the development of heart failure . Therefore, the sodium content in the diet is limited to 2.0-2.8 g/day (4-5 g of table salt). The food is not salted. In the absence of edema and high blood pressure, 2-3 g of salt are acceptable in the diet for adding salt to prepared foods, and if they are present, salt is completely excluded from the diet, and salty foods are also excluded - semi-finished products, canned food, smoked meats and pickles.

The amount of free fluid consumed is calculated from the ratio: 600 ml + daily diuresis volume + extrarenal causes of dehydration. On average - 800-1000 ml of liquid. To monitor fluid intake, it is necessary to weigh the patient daily and determine urine output for the previous day. The increase in body weight between dialysis sessions should not be more than 1.5-2 kg. Excessive consumption of free fluid promotes overhydration hyponatremia develops , and edema appears.

To compensate for the loss of vitamins during regular hemodialysis, it is recommended to supplement the diet with multivitamin preparations (group B, C, E), 1-2 tablets per day and taking vitamin D , since such patients develop D-hypovitaminosis . Additional intake of beta-carotene and vitamin A is undesirable.

The intake rates for phosphorus, potassium and calcium are determined primarily by laboratory and clinical indicators. In hemodialysis patients, hyperkalemia is associated with a high risk of death. Therefore, the amount of potassium intake in dialysis patients should not exceed 3 g potassium/day. Potassium is found mainly in fruits/dried fruits (raisins, dates, apricots, figs), bananas, nuts (peanuts, walnuts, pistachios, hazelnuts), legumes, mushrooms, garden greens (spinach, parsley, dill), rice, baked goods from wholemeal flour, vegetable broths, chocolate, fruit juices, ketchup, instant coffee, cocoa. The patient can eat no more than 1 vegetable and 1 fruit (in any form) per day. At the same time, raw vegetables and fruits must be peeled, washed with water and left in water for 2-3 hours, since potassium dissolves well in water.

The requirement for magnesium in patients on hemodialysis is 200–300 mg/day. Hypermagnesemia due to the relatively low content of magnesium in food and its low absorption in the intestine (40-50%) is less common than hyperkalemia, however, it is important to control the prescription of drugs containing magnesium ( magnesium sulfate , antacids), since it can cause severe hypermagnesemia with respiratory depression, neurological disorders.

The calcium requirement of patients on hemodialysis is at least 1.5 g/day. Excessive calcium intake is caused by the prescription of calcium-containing agents designed to bind phosphates ( calcium acetate , calcium carbonate , calcium gluconate ). Excessive calcium intake leads to hypercalcemia as well as vascular/tissue calcification. If there is no need to control phosphorus with calcium-containing products, it is recommended to reduce calcium intake to 900-1000 mg/day.

The need for phosphorus in the diet of a healthy person is 1600-1700 mg/day. During one hemodialysis procedure, an average of 250 mg of phosphorus is removed. That is, hemodialysis does not ensure the removal of phosphorus from the body in the required amount and cannot of hyperphosphatemia Since increased phosphorus content significantly increases the risk of myocardial infarction and the development of cardiovascular diseases, phosphorus intake during dialysis should be strictly limited. Since organic phosphorus is the most bioavailable, it is necessary to limit the content of animal products first of all to animal products containing it in large quantities and to a lesser extent to plant products.

Considering that protein is the main source of phosphorus, it seems advisable to include in the diet foods with a minimum phosphorus content in relation to protein - egg whites, sea fish, chicken drumstick, beef, turkey fillet, pork, cod and limit foods such as cheese, milk, muesli, bran, whole grain bread, legumes, cocoa, cereals, cottage cheese, nuts. If it is impossible to normalize phosphorus levels, calcium-containing/calcium-free drugs that bind phosphates are prescribed.

The diet for kidney hemodialysis involves the exclusion of a number of foods from the diet. List of products prohibited for consumption during dialysis: concentrated broths with meat/fish/mushrooms, fatty meat of animals and waterfowl, legumes (except soy protein), sausages, smoked meats, liver, brains, kidneys, canned snack foods, hard/processed cheeses, salted/fermented foods and vegetables rich in oxalic acid, hard-boiled eggs, refractory animal fats, margarine, chocolate, peaches, apricots, grapes, cherries, figs, black currants, bananas, dried fruits, peppers, cinnamon, horseradish, mustard, cocoa .

To diversify the diet and improve the taste of salt-free dishes, various methods of culinary processing of foods are used, including frying and stewing, adding spices, natural vinegar, citric acid, and using homemade sauces.

To improve suppressed appetite, the list of products can be expanded by including alcoholic beverages in the diet (in the absence of contraindications) - dry/semi-dry grape wine, vermouth, sherry or spirits, the volume of consumption of which (in terms of ethyl alcohol) should not be consumed by women exceed 20 g/day and 40 g/day for men. It is advisable to eat meals in small portions 5-6 times a day.

The essence of the diet

Hemodialysis is the purification of the patient’s blood using a machine that duplicates the work of the kidney. Treatment will not bring proper results if the patient does not follow table No. 7d.

The diet aims to provide the body with balanced nutrition, taking into account the characteristics of metabolism and protect it from unwanted intoxication.

Table No. 7g has a good energy value of 2800-3000 calories, which satisfies the patient’s physiological nutritional needs.

Chemical composition of the diet:

• Carbohydrates – 400-450 grams (100 grams of sugar);
• Proteins – 60 grams;
• Fats – 100-110 grams.

In case of kidney disease, first of all, the amount of consumption of protein-containing foods is reduced, so diet No. 7a allows only 20 grams of protein, diet No. 7b - 40 grams of protein per day. During hemodialysis with severe renal failure, the protein norm is higher, because the artificial kidney device helps break it down.

The volume of free fluid is reduced to 600-800 milliliters per day.

Diet No. 7g is salt-free, all food is consumed in fresh form. In cases where there is no edema or hypertension, the urologist makes an exception and allows the patient to consume 2-3 grams of sodium chloride per day.

Authorized Products

The diet of hemodialysis patients includes the consumption of salt-free bread and vegetarian soups with the addition of vegetables and cereals, as well as cabbage soup, beetroot soup, and borscht. For main courses, we recommend lean types of red meat (veal, beef), chicken, turkey, rabbit, which are served boiled. Pre-boiling the meat is mandatory, since the process of cooking in large quantities of water removes nitrogenous substances from the food.

After boiling, the meat can be further cooked. For fish, low-fat sea fish or river fish (pollock, pike, hake, pike perch, cod), which are prepared in a similar way, are recommended.

Vegetables and garden herbs (tomatoes, carrots, dill, lettuce, cucumbers, beets, parsley, cauliflower, tomatoes, green onions, potatoes) that are boiled or stewed are allowed as side dishes. Chicken eggs are allowed to be consumed in the amount of 2-4 pieces per week in the form of a steamed protein omelet or soft-boiled. In the absence of restrictions, it is allowed to include milk and fermented milk products in the diet in the amount of 200-300 g per day.

Homemade white sauces with sour cream/milk, unsalted vegetable vinaigrette, and vegetable/fruit salads are allowed. Unsalted butter and various vegetable oils are recommended as fats. Fruit/berries can be consumed in various forms, taking into account the potassium content, if its limitation is prescribed to the patient. Drinks you can drink include rosehip infusion, weak tea and coffee, and freshly prepared fruit juices.

Table of permitted products

Several daily menu options

Creating a special diet is a responsible matter. There are ready-made examples of diet menus for dialysis. We offer the most popular list of dishes for any day of the week:

Fully or partially limited products

The diet for patients undergoing hemodialysis involves the exclusion from the diet of concentrated meat/fish/mushroom broths, various refractory animal fats, fatty meats, foods high in salt (canned food, hard/processed cheeses, chips, bouillon cubes, salted nuts, sausages, sauces, marinades, ketchups, salted butter, margarine, canned vegetables), legumes, liver, brains, kidneys, smoked meats, hard-boiled eggs, cereals and pasta, dairy products.

Limit the consumption of foods containing a lot of potassium - curry, mushrooms, coffee, milk powder, fruit juices, sorrel, bananas, sea fish, seeds, sesame, nuts, soy products, chocolate, milk formula, dried apples, peanut butter, dried fruits, rhubarb , ketchup, spinach, beets, beer, avocado, fruit juices, tomato sauce, apricots, molasses, grapes, cherries, figs, lentils.

Products containing phosphorus are subject to restrictions: bran, nuts, whole grain bread, cereals, cocoa milk, cheese, eggs, legumes, muesli, cottage cheese. Strong tea/coffee, cocoa, and sodium mineral waters are excluded from drinks.

Table of prohibited products

Reviews and results

A strict diet for patients on hemodialysis is a vital necessity, especially for patients with high blood pressure, edema and disorders of phosphorus-calcium metabolism. According to patient reviews, it is difficult to get used to unsalted or low-salt food; the dishes are tasteless, but there is no choice.

• “... After toxic damage to the kidneys and the development of chronic kidney disease, I was prescribed hemodialysis. There were bad tests, constantly elevated blood pressure, and swelling. A therapeutic salt-free diet was prescribed. It was very difficult to get used to unsalted food right away. Garden herbs (parsley, dill, garlic, onions, parsnips) helped out, and I also made sauces based on milk and cream. I had to strictly control my diet. I cook everything in vegetable oil. So far I’m sticking to the diet normally, and there’s nowhere to go, you need to adapt if you want to live.”

Energy and Protein

Nutritional status is one of the main factors determining the quality and length of life on dialysis, as well as the effectiveness of the treatment. The more protein a patient consumes, the longer his life expectancy. Long-term survival on a diet with a daily protein content of 1.29 g/kg/day is 10 times higher than on a protein quota of 0.63 g/kg/day.