Dietary Related Information for Kidney
Sufficient calorie requirement is very important in patients with chronic kidney disease. If the calorie requirement is not adequate, proteins of body are used as a source of energy. This will not only lead to malnutrition but also lead to production of greater amounts of waste products of protein breakdown.
Most patients with chronic kidney disease say ‘I have kidney problem and thus I should not be consuming food items that contain protein.’
But this is just a myth. Protein builds, repairs and maintains body tissues. It also helps the body fight infections and heal wounds. As the body breaks down protein foods, a waste product called urea is formed. If this is not eliminated, too much urea in the blood may cause tiredness, nausea, headaches and a bad taste in your mouth. But if you eat too little protein, muscle mass may be lost leading to fatigue and weight loss . Therefore, enough protein is required for the body, at the same time limiting the amount of urea formed.
Foods like meat, fish, poultry, eggs, tofu, milk and milk products are high in protein.
The excretion of sodium decreases as renal failure progresses leading to increase in blood pressure and swelling. In such cases, sodium has to be restricted. If the blood pressure is normal and there is absence of edema, in such cases sodium need not be restricted and can be taken in moderation. Thus, sodium requirements should be totally indivualized.
Most of the convenient and popular food items such as farsan, chips, biscuits, sandwiches, noodles, chinese, chaats, panipuri, pizzas, papads, pickles etc are all high in sodium.
The failing kidney cannot excrete potassium adequately. This increases the potassium concentration in the blood which may cause heart problems. In such cases potassium has to be restricted. Leaching of vegetables and low potassium fruits should be encouraged. Fruit juices, coconut water, soups, dry fruits are high in potassium. However not all patients retain potassium and thus diet should be individualized based on the patients requirements.
Phosphorus is a mineral which helps keep bones strong and healthy. It may be referred to as phosphorus or phosphate. As kidney function declines, the blood phosphate level will rise, causing itchy skin, painful joints, and loss of calcium from bones. Therefore, the amount of phosphorus in the diet needs to be controlled. Phosphorus rich foods include milk and milk products, meat, fish and poultry. However, milk products and protein foods are also needed for overall good nutrition. Generally, foods with very high levels of phosphorus, such as seeds, nuts, dried peas, beans and bran cereals, are not included in the daily eating plan.
Read product labels carefully for hidden sources of phosphorus such as phosphoric acid and sodium phosphate.
Calcium & Vitamin D
Calcium and Vitamin D are needed for strong bones and are carefully regulated by healthy kidneys. Damaged kidneys may not be able to activate Vitamin D into a usable form. People with chronic kidney disease should only take calcium and Vitamin D as prescribed by their physician and monitor their levels regularly. Dairy products such as milk and milk products (curd, paneer) are good sources of calcium.
As kidney function decreases, the kidneys may not produce as much urine as before, and your body may become overloaded with fluid. In such cases, it is necessary to restrict the intake of fluids. Excessive fluid intake results in swelling, breathlessness and high blood pressure. In some cases where urine output is adequate and there is no swelling, fluid restriction may not be necessary. Fluids include any liquid at room temperature i.e. water, ice, milk, buttermilk, soup, juices, soft drinks, dal, ice creams etc.
Once a patient with chronic kidney disease is put on dialysis, they need to be counseled again. Reframing of the diet is very important as otherwise the patient continues the same diet which was previously prescribed for conservative management of kidney disease.
High energy is recommended to meet the body needs and minimize tissue protein breakdown.
During every dialysis, 12-20g of protein is been lost. The protein requirement increases due to loss of protein during dialysis. If enough protein is not being consumed, there will be muscle breakdown leading to fatigue and weakness. Atleast 50% of the protein should be of high biological value (HBV). HBV sources are eggs, milk and milk products. This protein intake helps to maintain positive nitrogen balance, replace losses and prevent undue accumulation of nitrogen waste between treatments.
Sodium restriction is necessary to control fluid retention and hypertension. Most convenient and favorite foods items such as farsans, chips, biscuits, sandwiches, noodles, Chinese, chaats, panipuri, pizzas, papads, pickles etc all are high in sodium. Check all labels to see how much salt or sodium foods contain per serving Make use of herbs and spices such as imli, kokum, lemon, ginger and garlic.
Potassium should be restricted moderately to prevent high concentration of potassium in the blood. Fruit juices, coconut water, dry fruits, soups are high in potassium.
Phosphorus is a mineral which helps keep bones strong and healthy. It may be referred to as phosphorus or phosphate. As kidney function declines, the blood phosphate level will rise, causing itchy skin, painful joints, and loss of calcium from bones. Therefore, the amount of phosphorus in the diet needs to be controlled. Phosphorus rich foods include milk and milk products, meat, fish and poultry. However, milk products and protein foods are also needed for overall good nutrition. Generally, foods with very high levels of phosphorus, such as seeds, nuts, dried peas, beans and bran cereals, are not included in the daily eating plan. Read product labels carefully for hidden sources of phosphorus such as phosphoric acid and sodium phosphate.
Vitamins and Minerals
A daily supplement of water soluble vitamins like vitamin B and C and minerals are usually given as these are lost during dialysis. Fat soluble vitamins (vitamins A, D, E and K) may be retained. Thus their supplements are avoided except vitamin D. Supplements of minerals like calcium, iron and zinc are recommended.
Usually 500 ml + urine output is recommended to avoid excessive fluid retention.
Limiting fluid may lead to increase in thirst. To help quench thirst, these options may be tried:
• Chew gum
• Drink from small cups
• Rinse your mouth
• Suck on a piece of ice, mints or hard candy (remember to pick sugar free candy if you have diabetes)
Myth 1- Diet for all kidney patients is same
Fact – Patients with diseases having normal kidney function such as urinary tract infection (UTI), kidney stones can have a liberal diet, and lots of water, coconut water etc but patients with poorly functioning kidneys such as chronic kidney disease need a more restricted diet.
Myth 2- I can use dietary salt substitutes such as Lona to reduce my blood pressure.
Fact – Do not use salt substitutes when kidney function is poor. Most of these use potassium instead of sodium which can lead to heart stoppage in a patient with kidney disease. Normal iodized salt should be used. Amount of salt intake depends on Fluid overload and sodium restriction. Sodium rich foods should also be restricted.
Myth 3- My kidneys are not functioning well hence I should drink more water.
Fact – Some people need to limit their fluids while others can drink any amount they wish or they feel thirsty. As kidney function decreases, the kidneys may not produce as much as urine as before & your body may become overloaded with fluid. On the other hand, patients with normal kidney function and with kidney stone or UTI need to drink plenty of water. Drinking extra water helps to flush substances that form stones from the kidneys.
Myth 4- I feel very weak, I should have fruits, fruit juices, dry fruits, coconut water, soups, and milk.
Fact – Fruits, fruit juices, coconut water vegetable soups will have lot of potassium, thereby, need a restriction in patients with chronic kidney disease. Dry fruits, beans, peas, dairy products are rich in phosphorus and thus should be avoided or be consumed in desirable amounts. But for patients having kidney stone consuming potassium rich foods will be helpful in treating the disease. Consuming excess salt, alcohol, animal protein, and carbonated beverages, oxalate rich foods such as spinach, chocolate, nuts should be avoided.
Myth 5- I have kidney disease I should avoid tomatoes, ladies fingers, brinjals as they contain seeds.
Fact – Most of the vegetables can be consumed, but if potassium in your blood is high you need to boil the vegetables / dal in water & discard the water. Even for kidney stone patients most of the vegetables are allowed in desirable amounts.
Myth 6- I should not have dal / pulses at all.
Fact – Dal / pulses can be consumed in moderate quantity prepared in medium consistency. Whole pulses & sprouts can be consumed occasionally. Soya has renoprotective properties so should be incorporated in the diet in desirable amounts. On the other hand, patients on dialysis should consume dal / pulses / milk and milk products / chicken / fish to meet their protein requirement. It is also important to eat the right amount of calories and other nutrients when receiving dialysis.
Myth 7- I should eat palak (spinach), beetroot to increase my haemoglobin.
Fact – The anemia (less blood), is not due to iron deficiency but deficiency of hormone called Erythropoietin, which is available in the market as injections and hence eating these food items is not likely to increase your haemoglobin.
Myth 8- I can’t work / exercise with my kidney disease.
Fact – Moderate exercise/ walk is permitted as per the comfort of each patient. Normal routine work should be promoted for such patients and is not harmful to the kidney.