Why should patients with chronic kidney disease have a low protein diet?
When kidney function is normal, protein in food is digested, absorbed and decomposed, and some of the protein and amino acids are absorbed and used by the body to maintain the normal physiological function of the body, and some of them are decomposed to produce nitrogenous waste products such as urea nitrogen, which are excreted from the kidneys. In chronic kidney disease, the ability of the kidneys to excrete these metabolic wastes is greatly reduced, so the protein catabolic wastes such as urea, creatinine, guanidine, etc. will accumulate in the blood and become uremic toxins. Reducing the protein intake of food, i.e. low protein diet, can reduce the production and accumulation of proteolytic metabolites, thus reducing the high workload of damaged kidneys and delaying the progression of renal insufficiency. Therefore, low-protein diet therapy is an important tool for non-dialysis treatment of patients with chronic kidney disease.
When is it appropriate to start a low protein diet?
The onset and progression of chronic kidney disease is a very slow process. Early treatment of chronic kidney disease is very important for the development and prognosis of the disease. The current accepted view is that protein restriction in the diet should be started as soon as kidney function is impaired.
What should I pay attention to when adhering to a low protein diet for a long time?
A reasonable low-protein diet can enable patients with chronic kidney disease to avoid malnutrition and requires the following points to be noted in daily life.
Low protein diet is not unlimited low, in general, ensure 0.6~0.8g protein/kg body weight per day.
Low-protein diet must have 50% from high-quality protein, such as milk, eggs, fish, poultry, meat and soybean products. The rest of the protein is provided by cereals, vegetables, fruits, etc.
Adequate calorie supply of 30~35 kcal//kg body weight per day must be ensured to maintain the ideal body weight.
Foods high in calories and low in protein, such as white potatoes, yams, taro, pumpkin, lotus root powder, potatoes, etc., should be consumed as much as possible. When patients eat less calories, they can add some foods with high sugar content such as honey, glucose, or vegetable oil to increase calories and meet the basic needs of the body.
In addition to this, pay attention to calcium supplementation, 1g~1.5g of calcium per day, while limiting the intake of phosphorus. Vitamin supply should be sufficient.
When urine volume decreases, below 1000ml per day, water intake should be appropriately restricted as well as water in food.
Can patients with chronic kidney disease eat soy products?
Although soy products are vegetable proteins, the essential amino acids (EAA) in their proteins are close to those of animal proteins in terms of quantity and proportion. Animal proteins contain about 45% EAA; plant proteins contain 35%-40% EAA (cereal proteins contain 35% EAA, bean proteins contain 39-40% EAA), bean proteins contain EAA is not much less than animal proteins, is the best plant-based high-quality protein. And legumes are rich in protein, while cholesterol content is much lower than animal protein, and rich in linoleic acid and phospholipids, in reducing vascular sclerosis, delaying the progress of CRF better than animal protein. Therefore, the notion that “soy products are not suitable for CRF patients” should be corrected.
How to calculate protein and calories?
Step 1: Calculate the standard weight: height – 105 = standard weight. A body weight not more than 10% above or below the standard weight is considered ideal weight. More than 20% is obese; less than 20% is wasting. For example, for a patient with a height of 170cm, the standard weight is 170-105=65kg.
Step 2: Calculate the daily calorie requirement, the total calorie requirement for the whole day = standard weight × daily calorie intake standard (30~35 kcal/kg). For example, if a wasted patient with light work should consume 30 kcal/kg per day, the total calorie requirement for the whole day is 30 kcal×65kg=1950 kcal.
Step 3: Calculate the daily protein intake: standard body weight × daily protein intake per kilogram of body weight = daily protein intake per day. Chronic kidney disease GRF <60ml, the recommended protein intake 0.6g/kg/day. For example: a patient weighs 65kg, protein intake is: 65×0.6=39g. It should be noted that quality protein should account for more than 50%.
Do you know the protein content of commonly used foods?
(grams or 10 ml of soy sauce). Avoid processed foods, such as pickled products, canned foods, and use soy sauce, umami vinegar, monosodium glutamate, chicken essence, bean paste, chili sauce ketchup and other condiments carefully. Condiments such as white vinegar, pepper, five spice, star anise, lemon juice, cilantro, green onion, ginger and garlic are available to increase the palatability of food. However, it is important to review regularly to avoid excessive restriction of sodium intake and the occurrence of hyponatremia.
What foods are high in uric acid?
Gout is a disorder of purine metabolism. The direct cause of gout is hyperuricemia, which is caused by an imbalance between uric acid production and renal uric acid excretion. Gout can cause kidney damage; reduced uric acid elimination in patients with chronic renal failure can also cause an increase in blood uric acid. Therefore, a high purine diet should be prohibited and a low purine diet should be chosen.
Foods with high purine content (150~1500mg%) mainly include: anchovies, sardines, fish, animal offal, gravy, etc.
Those with high purine content (75~150mg%) also include lentils, carp, cod, halibut, sea bass, eel, shellfish, eel, prosciutto, pork, beef, chicken, duck, rabbit, etc.
Those with less purine content (<75mg%) are asparagus, cauliflower, string beans, green beans, peas, spinach, mushrooms, cereals, mackerel, herring, white fish, ham, lamb, etc.
Those with little or no purine content are cereals, such as rice, flour, soda crackers, macaroni, etc. Vegetables include cabbage, carrot, radish, celery, cucumber, eggplant, kale, lettuce, cut beans, squash, zucchini, tomato, yam, potato, etc. Various kinds of dairy, eggs, fruits, sweets, etc.
Reasonable cooking methods can reduce the purine content of food, such as boiling meat first and discarding the soup before cooking. In addition, chili, curry, chemical pepper, mustard, and other food seasonings can excite the plant nerves and induce acute attacks of gout, and should also be avoided in large quantities.