Kidney Health 10 min read·Updated 22 July 2026 Clinician-reviewed

Stages of Kidney Disease Explained

A UK Consultant Nephrologist on how chronic kidney disease is staged, what eGFR and urine ACR mean, and the tests and timelines for each stage.

  • Clinically Reviewed
  • NHS & NICE Aligned
  • UK Evidence-Based
  • Last Reviewed 22 July 2026

Professor Mohammed Mahdi Althaf

Consultant Nephrologist & Acute Physician

View Credentials

Professor Mohammed Mahdi Althaf

MD, MSc, PgDip (Clin Ed), FRCP, FHEA, FASN

Consultant Nephrologist & Acute Physician · GMC 7216325

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Direct answer

CKD is staged by eGFR (kidney filter function) and urine ACR (protein leak). Stage 1–2 are usually silent; stage 3 is when symptoms may start; stage 4 needs specialist input; stage 5 needs dialysis or transplant. Early detection is the key to slowing progression.

Key recommendation: Stage 1–2: eGFR ≥ 60 with kidney damage — usually silent.

Quick answer

✓ Best choices

  • Lower-potassium fruit: apples, pears, berries, grapes, pineapple
  • Vegetables prepared with the leaching method when potassium is a concern
  • Whole grains: oats, basmati rice, pasta, couscous, sourdough
  • Lean protein in measured portions: fish, chicken, eggs, tofu

✓ Foods to limit

  • Added salt and high-sodium processed foods
  • Phosphate additives (E338, E339, E340, E450, E451, E452) in processed meats, fizzy drinks, instant foods
  • Very high-potassium foods if your blood potassium is rising
  • Sugary drinks, energy drinks and ultra-processed snacks

Key takeaway

CKD is staged by eGFR (kidney filter function) and urine ACR (protein leak). Stage 1–2 are usually silent; stage 3 is when symptoms may start; stage 4 needs specialist input; stage 5 needs dialysis or transplant. Early detection is the key to slowing progression.

Who should be cautious

People on dialysis, post-transplant, pregnant or breastfeeding, or taking prescription medication — confirm with your renal team before changes.

Stages of Kidney Disease Explained

How CKD is staged

The two numbers that define CKD are eGFR (from a blood test) and urine ACR (from a urine test). eGFR estimates filtration rate; ACR estimates protein leak. Together they give the stage and the risk of progression. A person with stage 3a and A3 (high proteinuria) is at much higher risk than someone with stage 3a and A1.

Stage 1 (eGFR ≥ 90)

Normal or high kidney function, but with evidence of kidney damage (protein in urine, blood in urine, structural abnormality on scan, or a known kidney disease such as polycystic kidney disease). Usually no symptoms. Action: treat the underlying cause, control blood pressure, review medications, annual monitoring.

Stage 2 (eGFR 60–89)

Mildly reduced kidney function with evidence of kidney damage. Still usually silent. Action: same as stage 1 — blood pressure control, diabetes management if applicable, avoid nephrotoxic drugs (regular NSAIDs, some herbal supplements), and monitor eGFR + ACR annually or more often if risk is higher.

Kidney Vitality is a daily multivitamin developed by a UK Consultant Nephrologist using renal nutrition principles. It contains no added potassium, magnesium, phosphorus or iron, and no herbal blends. See the formulation.

Stage 3a (eGFR 45–59) and 3b (eGFR 30–44)

Moderately reduced kidney function. Stage 3b is where symptoms often begin: fatigue, nocturia, mild ankle swelling, and rising blood pressure. Action: BP target usually < 140/90 (or lower if diabetic), statin for cardiovascular risk, review potassium and phosphate, consider referral to a renal dietitian. Nephrology referral if ACR > 70 or rapid decline.

Stage 4 (eGFR 15–29)

Severely reduced kidney function. Symptoms become more noticeable: anaemia, itchy skin, poor appetite, cramps. Action: mandatory nephrology referral. Planning for dialysis or transplant begins. Renal dietitian input for potassium, phosphate and protein. Erythropoietin may be needed for anaemia. Bone health review (vitamin D, calcium, PTH).

Stage 5 (eGFR < 15)

Kidney failure — also called end-stage renal disease (ESRD). Symptoms include nausea, breathlessness, severe fatigue, confusion and marked swelling. Action: dialysis (haemodialysis or peritoneal dialysis) or kidney transplant. This stage requires coordinated care by a multidisciplinary renal team.

Kidney Disease Symptoms — Stage by Stage
Related reading: Kidney Disease Symptoms — Stage by Stage.

Key practical tips

Designed for quick scanning — what to order, what to avoid, sensible portions, common mistakes.

  • Build a kidney plate: ½ vegetables and salad, ¼ whole-grain carb, ¼ protein
  • Cook from scratch when you can — it's the easiest way to control hidden salt and phosphate
  • Read labels for sodium ≤ 0.3 g per 100 g (low) and any 'E3-/E4-' phosphate additives
  • Discuss potassium and phosphate targets with your renal dietitian — they vary by stage

Clinical guidance

TL;DR summary

CKD is staged by eGFR (kidney filter function) and urine ACR (protein leak). Stage 1–2 are usually silent; stage 3 is when symptoms may start; stage 4 needs specialist input; stage 5 needs dialysis or transplant. Early detection is the key to slowing progression.

Key takeaways
  • Stage 1–2: eGFR ≥ 60 with kidney damage — usually silent.
  • Stage 3a–3b: eGFR 30–59 — fatigue and swelling may appear.
  • Stage 4: eGFR 15–29 — nephrology referral needed.
  • Stage 5: eGFR < 15 — dialysis or transplant planning.
  • Urine ACR (protein leak) determines risk alongside eGFR.
Kidney Diet & Nutrition Considerations

At every stage of chronic kidney disease, what you eat shapes how the kidneys cope day-to-day. UK renal guidance (NICE NG203, KDIGO 2024, KDOQI 2020 nutrition) focuses on four levers: sodium (salt), potassium and phosphate awareness, sensible protein intake, and an overall whole-food, Mediterranean-style pattern. Targets are individual — your renal team uses your bloods (eGFR, potassium, phosphate, bicarbonate) to personalise them. Aim for a balanced plate built around vegetables, lower-potassium fruit, whole grains, modest portions of fish or lean protein, and unsaturated fats such as olive oil.

Foods to prioritise

  • Lower-potassium fruit: apples, pears, berries, grapes, pineapple
  • Vegetables prepared with the leaching method when potassium is a concern
  • Whole grains: oats, basmati rice, pasta, couscous, sourdough
  • Lean protein in measured portions: fish, chicken, eggs, tofu
  • Extra virgin olive oil as the main cooking fat (PREDIMED-style pattern)

Foods to limit

  • Added salt and high-sodium processed foods
  • Phosphate additives (E338, E339, E340, E450, E451, E452) in processed meats, fizzy drinks, instant foods
  • Very high-potassium foods if your blood potassium is rising
  • Sugary drinks, energy drinks and ultra-processed snacks

Potassium, phosphate and protein needs vary between individuals — please confirm personal targets with your renal team or dietitian. Browse the Kidney Diet Hub for more guides in this cluster.

Frequently asked questions

What are the 5 stages of kidney disease?

CKD is staged by eGFR (estimated glomerular filtration rate). Stage 1: eGFR ≥ 90 with kidney damage. Stage 2: eGFR 60–89 with damage. Stage 3a: eGFR 45–59. Stage 3b: eGFR 30–44. Stage 4: eGFR 15–29. Stage 5: eGFR < 15 (kidney failure).

What is eGFR?

eGFR is a blood-test estimate of how well your kidneys filter waste. It is calculated from serum creatinine, age and sex. A healthy adult eGFR is typically above 90. eGFR naturally declines slightly with age.

What is urine ACR?

ACR (albumin-creatinine ratio) measures protein leak in urine. It is used alongside eGFR to stage and risk-stratify CKD. ACR categories: A1 (< 3 mg/mmol, normal), A2 (3–30, moderately increased), A3 (> 30, severely increased).

When should I see a kidney specialist?

NICE NG203 recommends nephrology referral if eGFR < 30, ACR > 70 mg/mmol, eGFR drops > 15% in a year, there is visible blood in the urine, or blood potassium is persistently high.

What is the best diet for chronic kidney disease?

For most adults with CKD the strongest evidence supports a Mediterranean-style, mostly plant-based pattern with reduced salt, sensible protein, and care with phosphate additives and very high-potassium foods. Exact targets for potassium, phosphate, protein and fluid should be set by your renal team based on your eGFR and recent blood results.

Nutritional challenges in kidney disease

Many people living with kidney disease have to limit foods because of potassium, phosphate, diabetes, dialysis, appetite changes or simply the time it takes to cook from scratch every day. That can make it harder to keep daily nutrition balanced — particularly for vitamins and minerals that food alone may not fully cover.

Kidney Vitality is a UK-formulated daily nutritional support product designed by Consultant Nephrologist Professor Mohammed Mahdi Althaf with renal nutrition in mind from the start. It keeps doses moderate, leaves out added potassium, phosphate and magnesium, and avoids megadose vitamin A — sitting alongside a kidney-friendly diet, not replacing it.

Why Kidney Vitality fits this need

Built around UK renal guidance

Aligned with NICE NG203, KDIGO 2024 and UK Kidney Association staging criteria.

Designed by a UK Consultant Nephrologist

Formulated and reviewed by Professor Mohammed Mahdi Althaf (GMC 7216325).

Evidence-based by design

Plain-English explanations of blood tests, staging and next steps.

Designed by a UK Consultant Nephrologist

Ready to support your kidney health?

If you have been researching kidney health, supplements, CKD nutrition or kidney-friendly living, Kidney Vitality was developed specifically around those principles by Professor Mohammed Mahdi Althaf (GMC 7216325). Nephrologist Developed Daily Multivitamin.

  • No Added Potassium
  • No Added Magnesium
  • No Added Phosphorus
  • No Added Iron
  • One capsule daily
  • UK GMP — BRCGS, NSF GMP, Halal
Subscribe & Save — £20.39/monthCheck your current multivitamin

✓ Free UK tracked delivery  ·  ✓ Delivered every 30 days  ·  ✓ Pause or cancel anytime  ·  ✓ Never run out

ComparisonKidney VitalityTypical high-street multivitamin
Added potassiumNoneOften included
Added phosphateNoneOften included (E338–E452)
Vitamin A (retinol)No megadoseOften high-dose retinol
Kidney-focused formulationYesNo — general population
Consultant Nephrologist involvementYes (GMC 7216325)No
UK GMP manufacturedYes (BRCGS, NSF GMP)Varies

Food supplement. Not a medicine and not a treatment for kidney disease. Speak with your GP, pharmacist or renal team before starting any new supplement, especially in advanced CKD, on dialysis, post-transplant, pregnant or breastfeeding.

Clinical reviewer

Professor Mohammed Mahdi Althaf

Consultant Nephrologist

Acute Physician

GMC 7216325

View Full Biography

Professor Mohammed Mahdi Althaf is a UK Consultant Nephrologist and Acute Physician with a special interest in chronic kidney disease, AKI prevention and renal nutrition. He combines hospital practice with patient education and clinical guidance review.

View professional profile →
View Credentials
  • MD
  • MSc
  • PgDip (Clin Ed)
  • FRCP
  • FHEA
  • FASN

About this article

Written for UK patients and based on:

  • NICE guidance
  • NHS resources
  • British Dietetic Association guidance
  • Kidney Care UK resources
View methodology

Each article is researched against current UK clinical guidance (NICE NG203, NG118, NG136), NHS patient resources, KDIGO and KDOQI international guidelines, and the British Dietetic Association Renal Nutrition Group. Drafts are written by the Kidney Vitality editorial team and reviewed by a UK Consultant Nephrologist before publication. Content is reviewed on a rolling basis and updated when guidance changes.

Editorial standards

  • Clinically reviewed
  • NHS-aligned
  • NICE-aligned
  • Evidence-based
  • Reviewed before publication
View full editorial process

Every article is researched and written by the Kidney Vitality editorial team using current UK clinical guidance (NICE NG203, NG118, NG136), NHS patient resources, KDIGO/KDOQI international guidelines, and British Dietetic Association renal nutrition guidance. Drafts are reviewed for clinical accuracy by Professor Mohammed Mahdi Althaf, MD, MSc, PgDip (Clin Ed), FRCP, FHEA, FASN (Consultant Nephrologist & Acute Physician, GMC 7216325) before publication. Content is updated when UK guidance changes.

References (4)View Sources
  1. NICE NG203: Chronic kidney disease — assessment and management
  2. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of CKD
  3. KDOQI Clinical Practice Guideline for Nutrition in CKD: 2020 Update
  4. British Dietetic Association — Renal Nutrition Group

Medical disclaimer

This content is educational only and does not replace personalised medical advice.

Read full disclaimer

This page is general information, not personal medical advice. If you have chronic kidney disease, are on dialysis, have had a kidney transplant, are pregnant or breastfeeding, or take prescription medication, please confirm any supplement with your GP, pharmacist or renal team before starting.

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