Kidney Health and Diet
In today’s world, lifestyle related diseases like diabetes, hypertension, and obesity are the prime causes for initiating and enhancing the rate of progression of chronic kidney disease.
There are many categories of diseases affecting the kidneys but for the sake of brevity we focus on the ones where diet has a role to play. We talk about renal stone disease, nephrotic syndrome, and renal failure particularly CKD (chronic kidney disease) where diet may have a role in preventing or aggravating the condition.
Diet for Chronic Kidney Disease (CKD)
At the outset, the role of dietary modifications are most obvious in renal failure, more so ¡n chronic kidney disease. There are many misconceptions ¡n this regard, causing severe and often inappropriate dietary restrictions of protein, salt and potassium in these patients.
To prevent kidney disease in today’s world it is important to eat a balanced, nutritious diet. It is extremely important to restrict the amount of junk food so that diabetes, hypertension and obesity can be avoided. Excess of animal protein (particularly red meat), high carbohydrate and high salt content foods, fructose-rich foods, artificial sweeteners, sweetened drinks (particularly sodas) are to be avoided.
In the context of renal stones, certain foodstuffs are not recommended. As calcium oxalate stones are the commonest, the usual recommendations for preventing stone recurrence are to ensure adequate fluid intake, reducing the consumption of salt and sugar. eating low fat dairy products and reducing the intake of non-dairy animal protein. It is Important to increase the fruit and vegetable intake in these patients, restrict high oxalate foods and not take vitamin C supplements in heavy doses for prolonged periods.
Diets rich In calcium are helpful ¡n preventing renal stones and recommended doses of calcium supplements do not increase the risk of stone formation. Beverages like tea and coffee do not increase the stone formation risk, while regular consumption of grapefruit juice does.
For patients with nephrotic syndrome (in which case there is massive amounts of protein ¡n the urine), a balanced diet with salt and fat restriction is prescribed. Fluid intake is restricted depending on the severity of the case and whether renal failure has set in.
Note – Cranberry Juice or its extract is useful in preventing urinary tract infections
Renal Diet Basics
All meal plans, including the kidney- friendly diet, should follow the basic rules of a balanced diet’, ensuring that there are appropriate amounts of calories, protein, carbohydrates, fats, minerals, vitamins and fluids. A proper diet plan helps to control diabetes, high blood pressure, hypercholesterolemia and prevents obesity all of which are known factors for the progression of renal failure.
Calories come from the proteins, carbohydrates and fats in our diet. The number of calories one needs depends on the age, gender, body size and activity level.
The current recommendations are that patients with CKD should take about 0.6 -0.8gm/kg body weight of high biological value proteins. There is no doubt that animal proteins have a high biological value, but it is also true that they cause more acid secretion as compared to vegetarian sources of proteins. Hence, a judicious mix of animal and vegetarian proteins should be the best bet for such patients. Ask you dietician or doctor for further details.
Protein Containing Foods In Our Diet
- Egg white
- Pulses and Legumes
- Nuts and Oilseeds
- Cheese and Milk Powder
Healthy sources of carbohydrates include fruits and vegetables. Rice, wheat and other cereals are all sources of carbohydrates in our daily diet. Sugar, honey, hard candies, soft drinks and other sugary drinks contain a lot of free sugar and are unhealthy sources of carbohydrates.
We need some tat to stay healthy. Fat gives us energy and helps us use some of the vitamins in our food. But too much fat can lead to weight gain and heart disease. Try to limit fat in your meal plan, and choose healthier fats when you can.
Too much sodium (salt) can lead to body swelling and raising the blood pressure. This can damage the kidneys more and make the heart work harder. Try eating fresh fruits and vegetables rather than crackers or other salty snacks. Avoid pickles, papads and other namkeen items, bakery products, tomato ketchups, soya sauce and other bottled sauces.
Note – Be careful not to consume salt substitutes or the low sodium salts like Lona, ¡t may contain high potassium and can be dangerous for renal failure patients.
The body needs some potassium to make muscles work, but too much potassium can be dangerous. When the kidneys are not working well, the potassium level may be too high or low. In patients of moderate or severe CKD, potassium intake needs to be limited, otherwise there may be serious consequences including death due to cardiac side effects, mainly arrhythmlas.
Low Potassium Diet (Eat These)
- Apple, pineapple, guava, cranberries, grapes, strawberries, cucumber
- Beetroot, pink radish, bottle gourd, snake gourd, ridge gourd, tinda, parwal, onion, green mangoes
- Rice, rice flakes, wheat semolina, vermicelli
- Fresh fish and chicken
High Potassium Diet (Avoid These)
- Bananas, melons, oranges, prunes, dry fruits and nuts
- Coconuts and coconut water
- Tomatoes, and green leafy vegetables
- Potatoes, sweet potatoes, tapioca Dried peas and beans Bran products and granola, ragi
Healthy kidneys keep the right balance of phosphorus in the body. When the kidneys are not working well, phosphorus can build up in the blood. Too much phosphorus in the blood can lead to weak bones that break easily.
Phosphorus in Foods
- Wheat and Wheat based products
- Legumes, pulses and nuts
- Milk and milk products meat, poultry, eggs and fish
- Carbonated drinks
- Rice and rice based products
- Fruits and vegetables
As kidney disease advances, the ability of the kidneys to excrete the water decreases. Thus, if one ¡s drinking too much water in severe renal failure the water may accumulate in the body, causing swelling. It also may increase blood pressure and precipitate heart failure causing severe breathing difficulty. Depending on the stage of kidney disease you may also need to cut back on some foods that contain a lot of water.
Very frequently vitamin D, folic acid alone or with iron is added to the diet of patients with CKD to make up for the deficit they have. But do not try taking vitamins on your own, it may be harmful for you. Check with your doctor first.