Chronic kidney disease (CKD) is a condition that occurs when the kidneys are damaged and not working as effectively to filter the blood. Nutrition plays an important role in managing CKD, supporting overall health, and reducing the risk of complications.
Dietary advice for kidney disease is highly individual and depends on factors such as the stage of CKD, blood test results, medications, and other health conditions such as diabetes or high blood pressure. For this reason, general dietary rules are rarely appropriate, and personalised dietitian-led guidance is recommended.
What Is Chronic Kidney Disease?
The kidneys play may important roles, such as removing waste from the body and balancing fluid levels. Chronic Kidney Disease (CKD), refers to a gradual decline in kidney function over time
The kidneys are responsible for filtering waste, balancing fluids and electrolytes, and supporting blood pressure and bone health. When kidney function declines, waste products can build up in the body. CKD is often diagnosed using blood and urine tests and is typically categorised into stages, based on estimated glomerular filtration rate (eGFR). Around 10% of the population has some stage of CKD.
Risk Factors
If you have or are at risk of type 2 diabetes, high blood pressure, or have a family history of CKD, this increases the risk – so it is important to get an annual test. Approximately 1 in 3 adults with diabetes (and 1 in 5 adults with high blood pressure) may have CKD.
Stages of Chronic Kidney Disease
CKD is commonly divided into five stages. In early stages, symptoms may be mild or absent. As kidney function declines, dietary adjustments may become more important to help manage symptoms and reduce complications.
To determine the stage of CKD that someone is at, a blood test is taken to check for their estimated Glomerular Filtration Rate (eGFR). This considers the creatinine levels in the blood, with the persons weight, age and gender. The less the kidneys work, the lower the eGFR number.
A urine test can also be carried out check the levels of substances called albumin and creatinine in your urine – known as the albumin: creatinine ratio, or ACR. A level of ACR more than 3mg/mmol is diagnostic of CKD.
For both eGFR and ACR, a higher stage indicates more severe kidney disease. The eGFR measurement may be inaccurate in those who have a much higher or smaller muscle than the average person of their age, sex and ethnic origin.
The Role of Nutrition in CKD
Nutrition can help manage CKD by supporting blood pressure control, managing electrolyte balance, and reducing the workload on the kidneys. However, dietary needs vary significantly between individuals. Working with a renal dietitian allows nutrition advice to be tailored safely, particularly when managing protein, sodium, potassium, and phosphorus intake.
Protein Intake and Kidney Disease
Protein requirements in CKD depend on disease stage and treatment plan. In some cases, moderate protein reduction may be recommended to reduce kidney workload, while in others, adequate protein intake is essential to prevent malnutrition.
A dietitian can help determine appropriate protein intake based on individual needs and medical guidance.
Sodium, Blood Pressure and Fluid Balance
Managing sodium intake is often important in CKD to help control blood pressure and reduce fluid retention. Lower sodium intake may help reduce swelling and support cardiovascular health.
Choose and prepare food with less salt (sodium)
- Buy fresh food most of the time to avoid added salt to pre-packaged foods.
- Cook food from scratch so that you know how much salt has been added.
- Use spices, onions, peppers and herbs instead of salt to flavour your food
- Check the sodium content on the nutrition label before you eat packaged foods. The traffic light system makes this easy – avoid foods with a red salt content.
- Rinse tinned vegetables that are in brine before eating
Potassium and Phosphorus Considerations
One of the kidneys’ most important roles is clearing potassium and phosphorus from the blood to avoid a build-up. When the kidneys stop working as well as they should, they don’t clear these minerals as much.
Potassium and phosphorus management depends on blood test results and CKD stage. Not everyone with CKD needs to restrict these minerals, and unnecessary restriction can negatively affect diet quality. Having a low potassium or phosphorus level is just as bad as having high levels. Low levels can also lead to heart failure!
Dietitian guidance ensures adjustments are made only when clinically indicated.
So how do you manage potassium & phosphorus levels?
- Track your lab results – they will tell you whether you need to eat a bit more or less high potassium foods
- Work with your dietitian to adjust your food sources
- Boil your vegetables – even just parboiling vegetables for 10 minutes will significantly reduce the potassium content of the food (remember to throw the water you used away, as this will contain all the potassium.
Plant-Based Diets and CKD
Plant-based eating patterns may offer benefits for kidney health when appropriately
planned. However, nutrient balance and mineral intake still require careful consideration in CKD.
When to Seek Dietitian Support
If you have CKD, personalised nutrition support can help manage symptoms, support
overall health, and reduce confusion around dietary advice. Working with a renal dietitian can provide tailored guidance based on your medical history, blood results, and lifestyle.
A renal dietitian can tell you:
- How much protein you should eat
- Tell you how much potassium and phosphate are fine to eat and which foods contain them
- How to reduce sodium (or salt) in your diet
- How to manage fluid intake and understanding the difference between dry and wet weight
- How to consume healthy fats to keep a healthy heart
- How to meal plan and what to eat when eating out
FAQ’s For Chronic Kidney Disease
Kidney damage is caused by alcohol intake
In reality, there are many things that can lead to kidney damage – with diabetes and high blood pressure being the most common. Drinking alcohol does not directly influence kidneys, but can increase the risk especially with a high intake. However, a moderate and low intake of alcohol is ok.
If you are at risk of CKD, you cannot change this
No! In fact, there are many dietary and lifestyle changes that can be made to reduce the risk of development, or further worsening of CKD. This is why seeing a renal nutritionist can make all the difference!
You will need dialysis if you have CKD
Not everyone who develops CKD will need dialysis. As CKD is a progressive disease, dialysis is often only needed when the kidneys have lost almost (or all) function – this is at stage 5, when eGFR is at 15 or less.
For more information and 1-1, personalised support, contact our kidney disease dietitian.
Reviewed and updated by Reema Pillai, RD– January 2026.
