Kidney Function Blood Test
Kidney FunctionKidneyAlcoholGeneral Health

Kidney Function Blood Test

Kidney Function Blood Test

November 23, 2020

Kidney Function Blood Test

Kidney Function Blood Test

Your kidneys are the two powerhouse filtration systems of your body. They clean your blood and get rid of lots of toxins - better than any detox drink or diet will do - so it’s a good idea to keep them healthy and check how they’re working.

What is a kidney function blood test?

A kidney function blood test is done to check the health of your kidneys. Your results show how well your kidneys are excreting toxins and waste from your body. Changes in how your kidneys are functioning, like renal insufficiency or kidney disfunction, can also be caused by other issues like hypertension and diabetes. Knowing how your kidneys are functioning can help you to understand how improving your lifestyle can affect your kidneys and your health. Many kidney diseases won’t show any symptoms and the only way to spot them early is to test your blood.

What do your kidneys do?

Kidneys are vital in removing waste from the body as well as producing essential hormones.. Your kidneys keep your blood clean and chemically balanced by excreting waste through your urine.

Functions of the kidneys:

  • Filter the blood of waste products such as urea, creatinine, and uric acid

  • Maintain levels of salt, potassium and water in the blood at a healthy level

  • Convert vitamin D from food and sunlight into the activated form of vitamin D which helps your muscles and bones work as they should do

  • Produce erythropoietin which is crucial in the production of red blood cells

  • Produce hormones which are important in the regulation of blood pressure

What to expect from the test

A kidney function test is carried out by taking a blood sample. This is a simple procedure carried out by one of our specialists. Your sample is then brought to the lab and analysed for the level of toxins and salt, giving a picture of how well your kidneys are functioning.

What can a kidney function test tell you?

A kidney function test can tell you whether you’re at risk of developing or suffering from chronic kidney disease. Your results can help you to make better lifestyle choices, like stopping smoking, changes to your diet and lowering your alcohol consumption.

Symptoms associated with kidney damage

A badly functioning kidney can cause chronic kidney disease, symptoms include:

  • Fatigue

  • Loss of appetite and weight loss

  • Swelling in the face, wrists, ankles or abdomen

During early stages of chronic kidney disease, no symptoms appear. So a kidney function blood test can give an indication to the health of the kidneys before damage becomes severe. Some people are at a higher risk than others of developing kidney problems:

  • Those with high blood pressure

  • Binge drinkers

  • People suffering from diabetes

  • People with existing heart problems

  • People who have a family history of kidney disease

  • Those taking certain medications (ibuprofen and aspirin)

  • Obese or overweight people

  • People suffering from continuous urinary tract infections

  • Smokers

Once kidney damage occurs it is irreversible. However, there are simple lifestyle changes you can make to prevent further damage.

What does a Kidney function test check?

A kidney function test measures the levels of toxins and some markers, like creatinine, within the bloodstream. Assessing the levels of these in the blood can help assess identify kidney related diseases.

Glomerular filtration rate (GFR) is the rate at which your kidney filters your blood’s plasma. If your GFR is low then it can be a sign that your kidneys are damaged or are not functioning at a healthy level. Early detection of a low GFR level can pick up early kidney disease.

Creatinine is a waste product produced from normal wear and tear of the muscles. Monitoring your creatinine levels can assess kidney function.

Urea nitrogen levels are used to determine how well your kidneys are working. This test is often called the BUN, or blood urea nitrogen, test. Urea is a waste product created in the liver during the breakdown of protein.

Smoking and your Kidneys

Smokers are at a higher risk of developing kidney disease. Renal failure is four times more likely in smokers compared to non-smokers. In fact, there is a notable increase with every 5 cigarettes smoked. Quitting smoking can have a range of benefits for your kidneys - including reducing your chances of getting kidney cancer and slowing kidney function decline.

Alcohol and your kidneys

Drinking alcohol affects your kidney function, so monitoring your alcohol consumption is essential to maintaining your kidney’s health. Not only does alcohol consumption lower your GFR level, but binge drinking can impair the balance that your kidneys maintain. Moderate alcohol consumption isn’t thought to have damaging effects on your kidneys, but drinking excessively regularly can do.

To manage your alcohol consumption, you can:

  • Limit alcohol consumption on any single occasion

  • Drink more slowly and drink with food

  • Alternate alcoholic drinks with water

Regular heavy drinking has been found to double the risk of kidney disease.

Being kind to your kidneys

There are lots of small lifestyle changes you can make to help your kidney do its job:

  • Regulate your salt intake - don’t eat too many salty foods

  • Make sure you keep yourself well hydrated, especially if drinking alcohol

  • Choose foods with low saturated and trans fats

  • Eat whole grain foods

  • Pick foods without added sugar

  • Limit your alcohol intake

  • Stop smoking

If you think you might have kidney problems, it's easy to get tested with Melio. Our General Health Check will check your kidneys, and give you an overview of your personal health. Find out more about getting a General Health Check here and book your test today.


“Diabetic Kidney Disease: Challenges, Progress, and Possibilities.” Clinical journal of the American Society of Nephrology : CJASN vol. 12,12 (2017): 2032-2045. doi:10.2215/CJN.11491116

Alicic RZ, Rooney MT, Tuttle KR. Diabetic Kidney Disease: Challenges, Progress, and Possibilities. Clin J Am Soc Nephrol. 2017 Dec 7;12(12):2032-2045. doi: 10.2215/CJN.11491116. Epub 2017 May 18. PMID: 28522654; PMCID: PMC5718284.

Ferenbach, David A, and Joseph V Bonventre. “Acute kidney injury and chronic kidney disease: From the laboratory to the clinic.” Nephrologie & therapeutique vol. 12 Suppl 1,Suppl 1 (2016): S41-8. doi:10.1016/j.nephro.2016.02.00365

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