Unknown facts of nutrition and kidney diseases

54-year old Abdul Latif, both a diabetes and high blood pressure patient, lost an alarming 10 kilos over the course of a few months. His dietary intake was compromised because of nausea and vomiting. He was referred to a Nephrologist (Kidney Specialist) and diagnosed with End Stage Renal Disease (ESRD). He was highly concerned about his health; with uncontrolled diabetes, high blood pressure and ESRD, he was now provided with a long list of dietary restrictions. He was really confused – what could he eat? Like Abdul Latif, many people lead a poor quality life with declining nutritional status due to lack of awareness and inappropriate dietary guidance.

In Pakistan, the frequency of renal disease is rising every day. The estimated incidence of End Stage Renal Disease (ESRD) in Pakistan is 100 per million populations. Chronic kidney failure is typically a progressive disease, defined as the presence of markers of kidney damage or pathological abnormalities in blood or urine tests for more than 3 months. Diabetes, high blood pressure, recurrent kidney stones or infections, Nephrotic syndrome and polycystic kidney disease are various causes of kidney-related diseases. Once renal function is affected, it gradually declines towards its end stage; but if properly managed, it can be delayed. There is a need to create awareness about renal diseases and their management among people who are suffering from the conditions mentioned above. There is a lack of awareness about diet among people, especially regarding what to eat and what to avoid in regards to different conditions and diseases, while maintaining a good nutritional status and healthy lifestyle. Patients are less often referred to a Registered Dietitian or Nutritionist.

Unknown facts of nutrition and kidney diseases
FAYZA KHAN, MSc (Nutrition), Registered Dietitian, The Kidney Centre PGTI President, Pakistan Nutrition and Dietetic Society (PNDS)

Kidneys play an important role in maintaining fluid and electrolyte balance, excretion of waste products and regulation of certain hormones. Therefore, people with kidney failure suffer from a variety of abnormalities and complications such as malnutrition (due to low appetite & anorexia, excess potassium in the blood (due to decreased potassium excretion), mineral imbalance and bone disorders, anemia due to impaired kidney function and decreased iron stores, and cardiovascular disorders (increased levels of fat in the blood).

Malnutrition is commonly seen amongst patients with kidney diseases due to inappropriate dietary intake and low appetite. Poor dietary management, lack of awareness and misconceptions regarding diet can affect the nutritional status of a patient very badly and make the prognosis worse. Nutritional status is affected by many underlying causes such as patient’s socioeconomic status, physical and psychological conditions. Timely and appropriate dietary advice with nutritional counseling plays an important role in combatting malnutrition and maintaining quality of life.

The aim and purpose of nutrition therapy is to maintain a good nutritional status and to prevent further complications of the disease which arise due to malnutrition. Whether it is early stage kidney disease, dialysis or post kidney transplant – at each stage, dietary management is slightly different according to the degree of kidney damage. There is no one diet that is right for the different types of kidney disease. When kidneys are damaged, toxic substances build up in the body. What you eat and drink can help slow down chronic kidney disease by reducing the accumulation of waste products in the blood. There are various recommendations and evidence-based clinical practice guidelines available for each stage of kidney disease, which are used by healthcare providers worldwide. It is important to talk with a registered dietitian about your individual nutrition needs, appropriate to the stage of kidney damage.

In early stages of CKD the nutritional goal should be well-controlled blood sugar, blood pressure and sodium restriction. In advanced stages, dietary modifications aim to help control associated complications. The diet should mainly focus on:

Energy and Protein Intake: Sufficient energy and protein intake is important to maintain an adequate nutrition and health status. Starch and cereals are the main source for providing energy, so keep a good portion at every meal. Unless you are overweight or have uncontrolled blood sugars, you may eat as you desire from this group. Easily digestible starch like rice and porridge can be a healthy alternative to roti in kidney patients who are already suffering from nausea and decreased appetite. Fat is the second important source of energy. Avoidance of preparing separate ‘special low fat meals’ for the patient can further deteriorate his/her nutritional status. Malnourished patients can include heart-healthy oils in the form of paratha, egg white omelet or liquid/soft margarine in their diet.

Protein: These include fresh meats, chicken, fish or egg white, and small servings of dairy products. Getting enough calories is an important way to use these smaller amounts of protein for important needs such as building muscles, healing wounds and fighting infection. Patients with chronic kidney disease often restrict meat completely. Moderate Protein instead of a NO Protein diet is recommended. However, excessive intake of protein should be restricted during the early stages of disease. Once dialysis is initiated, the patient requires a good amount of protein due to the increase losses of protein during dialysis.

Sodium: A mineral naturally found in foods, sodium intake is restricted in order to control high blood pressure and fluid retention. It is found in large amounts in table salt and in foods that have added table salt such as seasonings like soy sauce, teriyaki sauce, most canned foods and processed meats. As a replacement, fresh herbs, lemon, vinegar, green chilies and mint can be used to make meals palatable.

Potassium: Another important mineral found in food, potassium helps the muscles and heart to work properly. Too much or too little potassium in the blood can be dangerous. In case of potassium restriction, one should be careful about completely eliminating potassium rich foods as it can compromise the caloric requirement of patients.

  • All fruits and vegetables have some potassium. Certain fruits and vegetables have more than others and should be limited, or avoided, depending on the patient’s potassium blood level.
  • Portion control is of prime importance in maintaining potassium levels.
  • Leaching out water from vegetables and daals (legumes) can reduce their potassium.

Traditionally in illness, patients and caregivers increase the use of meat extracts / broths and juices. These should be completely avoided due to their high potassium content.

Calcium and Phosphorus: Bone-mineral disorder is a complication that may also occur due to hormonal imbalance. Calcium is an important mineral for building strong bones. However, foods that are good sources of calcium are also high in phosphorus. Eating foods high in phosphorus will raise the amount of phosphorus in blood. Rich sources of phosphorus include processed meats such as deli meats, sausages and hot dogs, bakery products and some beverages such as cola and malt-based drinks. One should include one cup of milk or milk products in his or her diet on a daily basis. In case of complete avoidance of any food group for a longer duration, certain deficiencies may develop which actually increase the risk of many other complications. The use of a phosphate binder, as prescribed by your physician, is very important for phosphate control.

Fluids: It is a common misconception among people that drinking excess fluids is beneficial for kidney disease, but this is not true for all types of kidney problems. Kidney failure or Nephrotic syndrome patients often require severe fluid restriction, while renal stone disease patients are suggested to increase their fluid intake. ‘Fluid’ is any food or beverage that is liquid at room temperature. Some examples are ice; beverages like coffee, tea, sodas, juice and water; frozen desserts such as ice cream, sherbet or popsicles; as well as gelatin, gravy and soups. Fluid intake is usually not restricted in the early stages of kidney disease. But fluid restriction may be advised at the later stages of renal failure to control edema & fluid retention. The patient may need to be given thirst quenching tips in case of fluid restriction. Use of ice bars and low intake of salt can help in reducing fluid intake.

Nutritional Assessment: This is most important in the diagnosis of any disease. After assessing the nutritional status, the dietitian can suggest a customized diet which can help the patient maintain his weight and good nutritional status. It is very important for people suffering from chronic kidney disease to consult a dietitian on a monthly basis. If any restrictions have to be included in the diet, then some replacement for that particular food should be suggested so that dietary restrictions may not affect the nutritional status. If the nutritional status is compromised and condition is critical, then visits should be more frequent, i.e. on a weekly basis. Disease-specific nutritional supplements / formulas can be used to meet the body’s increased nutritional needs during illness. Malnutrition is a vicious cycle. The person who is malnourished is likely to have more complications, frequent episodes of illness and hospitalization. Similarly, frequent hospitalization and episodes of illness make the person malnourished. So it is highly important to understand and realize the importance of early diagnosis of malnutrition in the management of any disease.

Timely nutrition intervention and counseling by a qualified Registered Dietitian / Nutritionist plays a crucial role, not only in prevention, but also in the management of certain conditions and diseases. It is the joint responsibility of the government, teaching institutions and media to create awareness about the importance of a healthy diet and lifestyle to prevent / help manage different diseases, amongst both health professionals and the general public.