Renal diet: what kidney patients eat in hospital and why

What it means

A renal diet is not one diet. It is a family of diets for people whose kidneys cannot clear waste, salts, minerals and fluid as they should. NIDDK puts it plainly: there is no single meal plan for everyone with chronic kidney disease. In the early stages there may be few limits; as the disease advances, more changes are needed.

The nutrients a renal diet commonly manages are:

• Sodium, because too much makes the body hold on to fluid, which can raise blood pressure and cause swelling.
• Potassium, because levels that are too high or too low can cause heart and muscle problems.
• Phosphorus, because a build-up can weaken bones and cause itching. Additives in packaged and processed foods are a major source.
• Protein, which may be moderated before dialysis and often needs to go up on dialysis, because dialysis removes protein from the blood.
• Fluid, which may be limited as kidney function falls and on dialysis. Anything liquid at room temperature, such as soup, counts.

The treating doctor and renal dietitian decide which of these apply and by how much, based on the stage, blood tests, medicines and dialysis.

When hospitals use it

It is ordered for inpatients with chronic kidney disease, patients on hemodialysis or peritoneal dialysis, and patients admitted with acute kidney problems. The Government of Odisha’s diet guidelines for public hospitals, for example, include a separate diet for acute and chronic renal disease, planned around low protein, low sodium and low potassium, with enough calories that protein is not used for energy. Current kidney guidance treats dialysis patients separately, because they usually need more protein, not less.

What it looks like on the tray

On an Indian renal tray, many of the changes are in what is missing:

• rice, with a measured portion of dal
• vegetables lower in potassium, or leached: peeled, cut, soaked and boiled with the water thrown away
• food cooked with little or no added salt, and no papad, pickle, namkeen or ready-made chutney
• fruit such as an apple in place of a banana or orange, when potassium is limited
• a set amount of milk or curd, since dairy is high in phosphorus
• egg white as a protein option, as in the Odisha renal menus

For a patient on a fluid limit, the dal, soup, tea, buttermilk and ice cream on the tray all count toward the day’s fluid.

Common mistakes on the ward

• One renal diet for everyone. A patient before dialysis and a patient on dialysis can need different protein, potassium and fluid rules.
• Coconut water from home. Attendees bring it as a healthy drink, but it contains significant potassium. A published case report describes severe hyperkalemia in a man with kidney disease who drank large amounts of king coconut water while taking medicines that also raise potassium.
• Low-sodium salt. The National Kidney Foundation lists salt substitutes among high-potassium foods and advises people on hemodialysis not to use those that contain potassium.
• Hidden salt. Papad, pickles, namkeen and packaged snacks carry sodium even when nothing is salted at the table.
• Uncounted fluid. Tea rounds, soup and dal add up for a patient on a fluid limit.
• Combined diets split apart. Kidney patients often also have diabetes or high blood pressure, and the tray has to satisfy every order.

How MedMeals handles it

The hospital configures its renal diets in MedMeals, for example separate diets before dialysis and on dialysis, and tags the items that suit each. A renal patient never sees the papad, and coconut water can stay off that patient’s menu on every ordering channel, including online orders placed by the family. Attendees order their own meals from a separate attendee menu, so family meals never mix with the patient’s plan. Nutrients stored per item (calories, protein, carbohydrates, sodium and more) help dietitians plan, diet changes reach the kitchen and nursing in real time, and the diet profile moves with the patient on transfer. See diet management or book a demo.