The kidneys filter blood, remove waste and extra fluid, and help keep salts and minerals in balance. They also make hormones involved in blood pressure, red blood cell production and bone health. Urine is one result of this work; the kidneys do much more than simply let water pass through the body.
Kidney health concerns how well those functions are maintained. Chronic kidney disease means a long-term problem with kidney function. It often develops without noticeable early symptoms and is commonly found through blood or urine testing. NHS guidance explains that many people with chronic kidney disease live with it for a long time without progressing to kidney failure.
- Kidneys filter waste and regulate fluid, minerals and several hormones.
- Early kidney problems may be found through testing rather than symptoms.
- Match nutrition and medicine decisions to individual clinical advice.
Understand the filtering units
Each kidney contains many small filtering units called nephrons. A filter lets waste and fluid pass into a tubule, which returns needed substances to the blood and helps form urine from what remains. This selective process maintains the conditions nerves and muscles need. Drinking extra water does not tell you how well those filters are working, and urine appearance alone cannot replace a kidney assessment.
Blood and urine tests give complementary information
A blood test measures creatinine, a waste product used to estimate the filtering rate, reported as eGFR. Urine testing can check for blood and for albumin, a protein; the albumin-to-creatinine ratio is often called ACR. NHS guidance uses these results together to assess kidney health and guide follow-up. Ask what each result means for you and when it should be repeated, rather than treating a single number as a diagnosis.
Manage the factors that affect the kidneys
Diabetes and high blood pressure are important reasons for kidney monitoring. Follow the care plan for those conditions and keep appointments. NHS prevention guidance also supports stopping smoking, balanced eating and regular activity. Take painkillers only as instructed; some anti-inflammatory medicines can harm kidneys when taken in excessive amounts or for too long. Ask a pharmacist if you are unsure what is suitable, particularly with an existing kidney condition.
Avoid a universal kidney diet
People with kidney disease may need individual advice about nutrients such as potassium or phosphate. That does not mean everyone should remove the same foods or buy the same mineral product. Before changing your diet, note the question you need answered: a test finding, a prescribed restriction or a symptom. Persistent swelling, blood in urine or unexplained changes in urination deserve medical assessment. Bring a medicine and supplement list so a clinician can assess the whole situation.
- Understand your blood and urine results as a pair.
- Ask whether nutrition advice applies to your stage and test results.
- Check medicines and supplements with the appropriate professional.
Sources & further reading.
The explanation and practical suggestions above draw on these references.
Educational preview with no named medical reviewer. General education and specification-based product comparisons · Updated 2026-10-06. Personal medical questions belong with a qualified professional.
Understand the supplement claims.
These profiles explain research relevant to this topic and the limits or interactions that matter. Inclusion is not a recommendation to treat a condition.
- AstragalusDo not use an astragalus capsule as unsupervised kidney treatment.
- Calcium citrateCalcium and vitamin D use may need monitoring in kidney disease.
- Casein proteinA prescribed kidney-related protein plan takes priority over gym supplement marketing.
- Electrolyte powderKidney conditions can change fluid and mineral requirements; seek a tailored plan.
- L-carnitineKidney-related carnitine management is a specialist context.
- Magnesium glycinateImpaired kidney function increases concern about excessive magnesium.
- Whey proteinPeople with kidney disease may need an individual protein plan rather than generic sports targets.
- LemongrassDo not use it as a kidney treatment; repeated leaf infusions have raised safety concerns.