Designing the Daily Food

Common principles for the diet plan.The major role of the kidneys is to remove waste products and purify blood.

Besides this, the kidney plays an important role in removing extra water, minerals and chemicals; it also regulates water and minerals like sodium, potassium, calcium, phosphorus and bicarbonate in the body.

In patients suffering from chronic kidney disease (CKD), regulation of fluids and electrolytes may be deranged. Because of this reason even normal intake of water, common salt or potassium can cause serious disturbances in fluid and electrolyte balance.

To reduce the burden on the kidney with impaired function and to avoid disturbances in fluid and electrolyte balance, patients with chronic kidney disease should modify their diet as per the guidance of the doctor and the dietitian. There is no fixed diet for CKD patients. Each patient is given a different dietary advice depending on clinical status, the stage of kidney failure and other medical problems.

Dietary advice needs to be altered for the same patient at different times.

Goals of dietary therapy in CKD patients: Slow down the progression of chronic kidney disease and to postpone the need for dialysis.

Reduce the toxic effects of excess urea in the blood.

Maintain optimal nutritional status and prevent the loss of lean body mass.

Reduce the risk of fluid and electrolyte disturbances.

Reduce the risk of cardiovascular disease.

General principles of dietary therapy in CKD patients

Restrict protein intake to <0.8 gm/kg of body weight/day for patients not on dialysis.

Patients already on dialysis require an increased amount of protein (1.0 -1.2 gm/kg body weight/day) to replace protein that may be lost during the procedure.

Supply adequate carbohydrates to provide energy.

Supply a moderate amount of fats. Cut down the intake of butter, ghee and oil.

Limit the intake of fluid and water in case of swelling (edema).

Restrict the amount of sodium, potassium and phosphorus in the diet.

Supply vitamins and trace elements in adequate amounts. A high fiber diet is recommended.

Details of selection and modification in diet of patients with CKD

High Calorie Intake :The body needs calories for daily activities and to maintain temperature, growth and adequate body weight. Calories are supplied chiefly by carbohydrates and fats.

The usual caloric requirement of CKD patients is 35 – 40 kcal/kg body weight per day. If caloric intake is inadequate, the body utilizes protein to provide calories. This breakdown of protein can lead to harmful effects such as malnutrition and a greater production of waste products. It is thus essential to provide an adequate amount of calories to CKD patients. It is important to calculate the caloric requirement according to a patient’s ideal body weight, and not current weight.

Carbohydrates

Carbohydrates are the primary source of calories for the body. Carbohydrates are found in wheat, cereals, rice, potatoes, fruits and vegetables, sugar, honey, cookies, cakes, sweets and drinks. Diabetics and obese patients need to limit the amount of carbohydrates. It is best to use complex carbohydrates from cereals like whole wheat and unpolished rice which would also provide fiber. These should form a large portion of the carbohydrates in the diet. All other simple sugar containing substances should form not more than 20% of the total carbohydrate intake, especially in diabetic patients.

Non-diabetic patients may replace calories from protein with carbohydrates in the form of fruits, pies, cakes, cookies, jelly or honey as long as desserts with chocolate, nuts, or bananas are limited.

Fats

Fats are an important source of calories for the body and provide two times more calories than carbohydrates or proteins. Unsaturated or “good” fats like olive oil, peanut oil, canola oil, safflower oil, sunflower oil, fish and nuts are better than saturated or “bad” fats such as red meat, poultry, whole milk, butter, ghee, cheese, coconut and lard.

Patients with CKD should reduce their intake of saturated fats and cholesterol, as these can cause heart disease.Among the unsaturated fats it is important to pay attention to the proportion of monounsaturated and polyunsaturated fats. Excessive amounts of omega-6 polyunsaturated fatty acids (PUFA) and a very high omega-6/omega-3 ratio is harmful while low omega-6/omega-3 ratio exerts beneficial effects. Mixtures of vegetable oil rather than single oil usage will achieve this purpose. Trans fat containing substances like potato chips, doughnuts, commercially prepared cookies and cakes are potentially harmful and should be avoided.

Restrict Protein Intake Protein is essential for the repair and maintenance of body tissues. It also helps in healing of wounds and fighting against infection. Protein restriction (< 0.8 gm/kg body weight/day) is recommended for CKD patients not on dialysis to reduce the rate of decline in kidney function and delay the need for dialysis and kidney transplantation. Severe protein restriction should be avoided however because of the risk of malnutrition.

Poor appetite is common in CKD patients. Poor appetite and strict protein restriction together can lead to poor nutrition, weight loss, lack of energy and reduction in body resistance, which increase the risk of death.

Proteins with high biologic value such as animal protein (meat, poultry and fish), eggs and tofu are preferred. High-protein diets should be avoided in CKD patients. Likewise, the use of protein supplements and drugs such as creatine used for muscle development are best avoided unless approved by a physician or dietitian.

Salt (Sodium) Restriction in Diet

Why is a low sodium diet advised for patients with CKD?

Sodium in our diet is important for the body to maintain blood volume and to control blood pressure.

Our kidneys play an important role in the regulation of sodium. In patients with CKD, the kidneys cannot remove excess sodium and fluid from the body so sodium and water build up in the body.

An increased amount of sodium in the body leads to increased thirst, swelling, shortness of breath and increase in blood pressure.

To prevent or reduce these problems, patients with CKD must restrict sodium intake in their diet.

What is the difference between sodium and salt?

The words sodium and salt are commonly used as synonyms.

Common salt (table salt) is sodium chloride and contains 40% sodium. Salt is the principle source of sodium in our diet. But salt is not the only source of sodium. There are quite a few other sodium compounds in our food, such as:

Sodium alginate: Used in ice-cream and chocolate milk

Sodium bicarbonate: Used as baking powder and soda

Sodium benzoate: Used as a preservative in sauce

Sodium citrate: Used to enhance flavor of gelatin, desserts and beverages

Sodium nitrate: Used in preserving and coloring processed meat

Sodium saccharide: Used as artificial sweetener

Sodium sulfite: Used to prevent discoloration of dried fruits

The above mentioned compounds contain sodium but are not salty in taste.

Sodium is hidden in these compounds.

How much salt should one take?

A typical daily intake of salt is about 10 to 15 grams (4-6 grams of sodium) per day. Patients with CKD should take salt according to the recommendation of the doctor. CKD patients with edema (swelling) and high blood pressure are usually advised to take less than 2 grams of sodium per day.

Which foods contain high amounts of sodium?

Foods high in sodium include:

Table salt (common salt), baking powder Processed foods like canned foods, fast foods and “deli” meats

Readymade sauces Seasonings and condiments such as fish sauce and soya sauce.

Baked food items like biscuits, cakes, pizza and breads Wafers, chips, popcorn, salted groundnuts, salted dry fruits like cashew nuts and pistachios

Commercial salted butter and cheese Instant foods like noodles, spaghetti, macaroni, and cornflakes

Vegetables like cabbage, cauliflower, spinach, radish, beetroot, and coriander leaves Coconut water

Drugs like sodium bicarbonate tablets, antacids, laxatives

Non-vegetarian foods like meat, chicken, and animal innards like kidneys, liver and Brain

Sea Foods like crab, lobster, oyster , shrimp, oily fish and dried fish

Practical Tips to Reduce Sodium in Food

Restrict salt intake and avoid extra salt and baking soda in diet.

Cook food without salt and add permitted amounts of salt separately. This is the best option to reduce salt intake and ensure consumption of the prescribed amount of salt in everyday diet.

Avoid foods with high sodium content (as listed above).

Do not serve salt and salty seasonings at the table or altogether remove the salt shaker from the dining table.

Carefully read labels of commercially available packaged and processed foods. Look not only for salt but also for other sodium containing compounds.

Carefully check the labels and choose “sodium-free” or “low-sodium” food products. Make sure however that potassium is not used to substitute sodium in these foods.

Check sodium content of medications.Boil vegetables with high sodium content. Throw away the water. This can reduce sodium content in vegetables.

To make a low salt diet tasty, one can add other spices and condiments such as garlic, onion, lemon juice, bay leaf, tamarind pulp, vinegar, cinnamon, cloves, nutmeg, black pepper, and cumin.

Caution! Avoid the use of salt substitutes as they contain high amounts of potassium.

High potassium content of salt substitutes can raise the potassium levels in blood to dangerous levels in CKD patients.

Do not drink softened water. In the process of water softening, calcium is replaced by sodium. Water purified by reverse osmosis process is low in all minerals including sodium.While eating at restaurants, select foods that contain less sodium.