Our kidneys are roughly the size of our fist and are situated between our ribs and waist. They do a wonderful job at filtering blood to remove unwanted waste products and to control levels of water within the body. The kidneys also produce important hormones. Dietary considerations play an important part in the management of chronic kidney disease. This article aims to provide general information and is not a substitute for specialist medical treatment.
What is Chronic Kidney Disease?
People with chronic kidney disease have altered kidney function or damage that has been present for three months or longer. The function of the kidneys is measured by something called the glomerular filtration rate (GFR). This reflects the amount of blood that the kidney’s have removed waste products from in one minute. We can only estimate this process based on creatinine levels in the blood, age and gender.
Stages of CKD
There are five stages of CKD. This is dependent of the individuals level of kidney function or damage e.g. protein or blood present in the urine. A blood or urine test is a good way to pick up on early stages of CKD. People can move between stages one and four but unfortunately cannot usually improve once the kidney function has declined to level five.
Stage one
GFR: 90ml/min/1.73m2
This stage often does not present with symptoms. There are signs of kidney damage yet the GFR is not decreased.
Stage two
GFR: 60 – 89ml/min/1.73m2
Once again there is usually no symptoms with stage three kidney disease. There is damage present and a slight reduction on the GFR.
Stage three
GFR: 30-59ml/min/1.73m2
The GFR is now quite significantly reduced. Individuals still may not show symptoms at this stage but dysfunction can be evident in other organs.
Stage four
GFR: 15-29ml/min/1.73m2
By this stage, kidney function is dramatically reduced. Individuals will start to show some symptoms. Damage pof other organs is more predominant and levels of creatinine and urea are increased in the blood.
Stage five – End stage kidney disease
GFR: Less than 15ml/min/1.73m2
Unfortunately once this point is reached there are many blood abnormalities in numerous organs – known as uraemia. It is essential that patients receive dialysis or a kidney transplant once the GFR drops down to 7-8ml/min/1.73m2. At this rate, the body can no longer maintain life.
Dietary guidelines for people with chronic kidney disease
Patients should not try and manage their CKD through their own research. It is important the appropriate advice and guidelines are followed.
Stages one – three
In the earlier stages of kidney disease it is often not essential to alter dietary intake. The management is based around:
- Ensuring that a healthy, balanced diet is followed
- Maintenance of a healthy weight
- Maintenance of muscle stores, strength and prevention of wasting.
- Avoidance of malnutrition
It was once thought that a low protein diet should be followed but this is no longer the case.
Stage four and five
Patients with stage four CKD will often require some nutrition intervention and most patients by stage 5 will require the restriction of certain nutrients and fluids. The dietitian and medical teams will base this on blood test results and physical examination.
Generally the following changes will need to be made to help manage the condition:
- Sodium should now be restricted if CKD is progressive and if patient is hypertensive.
- Often potassium reaches or exceeds 6.0mmol/L in which case a potassium restricted diet must be followed.
- Phosphate levels also often become abnormally high and phosphate binders need to be given with meals and/ or a phosphate restricted diet followed.
- Fluid restriction is often necessary to manage oedema and hypertension, particularly in end stage kidney disease.
- An increased protein intake is recommended.
- Energy intake should be adequate to meet requirements in order to maintain weight and muscle stores.
- Physical activity should be encouraged as per the physiotherapist’s recommendations.
Contact us for results focused nutritional advice
This article was written by our dietitian Belinda Elwin who is a Dietitians Association of Australia member and Accredited Practising Dietitian and Nutritionist. If you have questions about nutrition guidelines for people with chronic kidney disease, make an appointment. We‘ll provide you with a simple and effective routine targeted to your concerns. Contact us today!
