Diet in Chronic Kidney Disease (CKD)
CKD stages 1-3 (eGFR 44-90)
In the early stages of kidney disease, it is important to protect the kidneys from further damage as best as possible. It is therefore important to:
- Have a healthy balanced diet;
- Limit salty foods and avoid adding salt;
- Work towards achieving a healthy body weight;
- Control your blood sugar levels if you have diabetes;
- Only drink alcohol in moderation.
Most people in the earlier stages of kidney disease do not need to follow a special diet.
Please see the information below for more details:
Healthy balanced diet
Having a healthy balanced diet is an important part of general health and achieving a healthy weight. For guidance on a healthy balanced diet, please see the EatWell guide below:
(To download this EatWell guide as a .pdf: click here).
For further information, please see the NHS Greater Glasgow & Clyde YouTube video on Diet and Chronic Kidney Disease:
https://www.youtube.com/watch?v=wZtw5tay0K4
Have less salt
A salty diet can lead to fluid retention and high blood pressure. The recommended daily salt intake is less than 6g per day (around 1 teaspoon). It is difficult to avoid salt completely as around 75% of the salt we consume is already present in food. Try to avoid adding salt at the table, and limit ultra processed foods as these can be very salty. It can be helpful to read food labels to check for salt. It is important to avoid low sodium salt substitutes (for example ‘Lo Salt’ or ‘So-Low Salt’) as they contain potassium salts which may be harmful in kidney disease.
For guidance on reducing salt in your diet, please see the following page from the British Dietetic Association’s ‘Food Facts’ page:
https://www.bda.uk.com/resource/salt.html
Achieving a healthy body weight
Maintaining a healthy weight is important for your general health including your kidneys. Body Mass Index (BMI) is a measure of whether you are a healthy weight for your height. For most adults, use the following BMI ranges to estimate whether you are a healthy weight:
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy |
| 25 – 29.9 | Overweight |
| 30 and above | Obese |
For guidance with calculating your BMI, and support with achieving a healthy body weight, please see the following link:
https://www.nhsinform.scot/healthy-living/12-week-weight-management-programme/
Clink the following link to download NHS Lothian’s leaflet ‘Working towards a healthy weight with kidney disease’: Working towards a healthy weight with kidney disease.
Physical activity
Being physically active can help you achieve a healthy weight, as well as helping you to feel good. All adults should aim to do 150 minutes of moderate intensity physical activity per week (roughly 30 minutes for 5 days per week).
For further information on exercise, please see the following links:
https://www.nhs.uk/conditions/nhs-fitness-studio/
Further support with achieving a healthy weight
If you would like more specialist support with managing your weight, please speak to your GP or consider self-referring to the NHS Lothian Weight Management Service:
https://services.nhslothian.scot/awmt2d/specialist-weight-management-support/
CKD stages 4-5 or on dialysis
In the more advanced stages of kidney disease, the kidneys do not filter out excess minerals as they should, and blood levels may rise. You may be referred to a Renal Dietitian to support you in making some changes to what you eat and drink to help prevent complications. All patient on dialysis will be seen by the Renal Dietitians. You may be advised to follow a potassium-lowering or phosphate-lowering diet depending on your blood test results. It is still important to follow a no added salt diet. You may also be required to follow a fluid restriction as your kidney disease progresses.
There is no such thing as a specific renal diet – advice will vary from person to person.
Potassium
Potassium is found naturally in a range of foods. You only need to follow a potassium-lowering diet if instructed by a member of your healthcare team. A Renal Dietitian can provide further guidance on which foods to choose.
For guidance on a potassium-lowering diet, please see the following link:
https://kidneycareuk.org/get-support/healthy-diet-support/lowering-your-potassium-levels/
Phosphate
Phosphate is found both naturally in a range of foods, and also artificially added (also known as food additives or ‘E numbers’) to many ultra processed foods to help extend the food’s shelf life or improve its flavour/appearance. Limiting ultra processed foods as much as possible can help lower your blood phosphate level. You only need to follow a phosphate-lowering diet if instructed by a member of your healthcare team. A Renal Dietitian can provide further guidance on which foods to choose.
For further information on phosphate, please see the following link:
https://kidneycareuk.org/get-support/healthy-diet-support/natural-phosphate-and-added-phosphate-ckd/
Some patients may still have a raised blood phosphate level even after making some dietary changes. In this case you may be prescribed phosphate-lowering medication to take with your meals (phosphate binders). It is important to always remember to take as prescribed with meals, as the medication works directly on the phosphate in the foods you eat.
Fluid
To prevent fluid retention, you may be asked to reduce the amount of fluid you consume (usually to 1 or 1.5 litres per day). This includes drinks and fluidy foods such as ice cream, jelly and sauce. Your Renal Dietitian can provide guidance on how to reduce the amount of fluid you consume.
For further guidance on reducing fluid, please see the following link:
https://kidneycareuk.org/get-support/healthy-diet-support/managing-your-fluid-and-salt-levels.
For more information about Renal Dietitians, please see the following links:
Dietary advice following a kidney transplant
Following a kidney transplant, any dietary potassium or phosphate restrictions can usually be relaxed. Before making any dietary changes, please check with your transplant doctor or dietitian whether it is safe to relax your diet depending on your blood test results. Is it still important to have no added salt. Many people find they feel much better once their new kidney is working well, and their appetite can improve. It is important to follow a healthy balanced diet, be physically active and to maintain a healthy body weight to help look after your new organ.
For further information please see the following link:
Acknowledgements
This page was updated in June 2024 by Annika Baird and Gillian Walker.