Kidney Health 9 min read·Updated 22 July 2026 Clinician-reviewed

10 Early Signs of Kidney Problems

A UK Consultant Nephrologist on the early warning signs of kidney disease — what to look for, what's usually harmless, and when to book the GP.

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

Professor Mohammed Mahdi Althaf

Consultant Nephrologist & Acute Physician

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Professor Mohammed Mahdi Althaf

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

Consultant Nephrologist & Acute Physician · GMC 7216325

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Direct answer

Early chronic kidney disease (CKD) is usually silent. The most useful early signs are foamy urine, ankle swelling, nocturia, fatigue, itchy skin and rising blood pressure. The only reliable way to detect CKD early is an annual eGFR blood test plus a urine ACR — both free on the NHS for at-risk adults.

Key recommendation: Most early CKD has no symptoms — testing matters.

Quick answer

✓ Best choices

  • Vegetables, lower-potassium fruit and whole grains
  • Sensible portions of fish, eggs, chicken or tofu
  • Olive oil and unsalted nuts in small amounts

✓ Foods to limit

  • Added salt and ultra-processed foods
  • Phosphate additives in processed meats and ready meals
  • Sugary and energy drinks

Key takeaway

Early chronic kidney disease (CKD) is usually silent. The most useful early signs are foamy urine, ankle swelling, nocturia, fatigue, itchy skin and rising blood pressure. The only reliable way to detect CKD early is an annual eGFR blood test plus a urine ACR — both free on the NHS for at-risk adults.

Who should be cautious

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

10 Early Signs of Kidney Problems

The 10 signs to watch for

  1. Persistent fatigue and reduced exercise tolerance.
  2. Foamy or bubbly urine that does not flush away (proteinuria).
  3. Swelling around the ankles, feet or eyes (oedema).
  4. Waking once or more at night to pass urine (nocturia).
  5. Itchy or dry skin not explained by eczema.
  6. New or worsening high blood pressure.
  7. Reduced appetite or a metallic taste in the mouth.
  8. Difficulty concentrating or 'brain fog'.
  9. Cramps or restless legs at night.
  10. Pale skin or breathlessness on exertion (anaemia of CKD).

Symptoms vs CKD stage

Stage 1–2 CKD: usually no symptoms — only detected on blood/urine tests. Stage 3a–3b: fatigue, nocturia and mild swelling may appear. Stage 4: itchy skin, anaemia, cramps and reduced appetite become common. Stage 5: uraemic symptoms (nausea, confusion, severe fatigue) — needs renal team input.

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.

Risk factors that should trigger testing

Annual eGFR + urine ACR is recommended (NICE NG203) for adults with: diabetes (type 1 or 2), high blood pressure, cardiovascular disease, family history of CKD, AKI in the past, long-term NSAID or lithium use, or age over 60. Black, Asian and Minority Ethnic adults are at higher risk and benefit from earlier screening.

What to do next

Book a GP appointment and ask for an eGFR (kidney function blood test) and a urine ACR (albumin-creatinine ratio). Both are free on the NHS. Take a home blood-pressure log if possible. If results come back abnormal, ask to be referred to nephrology when eGFR < 30, ACR > 70 mg/mmol, or eGFR drops > 15% in a year.

How to Improve Kidney Function Naturally
Related reading: How to Improve Kidney Function Naturally.

Key practical tips

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

  • Cook from scratch when you can
  • Read sodium labels (≤ 0.3 g per 100 g is low)
  • Take any concerns to your GP or renal team early

Clinical guidance

TL;DR summary

Early chronic kidney disease (CKD) is usually silent. The most useful early signs are foamy urine, ankle swelling, nocturia, fatigue, itchy skin and rising blood pressure. The only reliable way to detect CKD early is an annual eGFR blood test plus a urine ACR — both free on the NHS for at-risk adults.

Key takeaways
  • Most early CKD has no symptoms — testing matters.
  • Foamy urine = possible proteinuria; book an ACR.
  • Ankle / eye swelling can signal fluid retention.
  • Nocturia (waking to urinate) is an under-recognised sign.
  • Loin pain is usually NOT CKD — think stones or UTI.
Kidney Diet & Nutrition Considerations

Diet is one of the most powerful tools you have to look after your kidneys. UK renal guidance points to a Mediterranean-style, reduced-salt pattern: plenty of vegetables, lower-potassium fruit, whole grains, sensible protein, beans and pulses in moderation, oily fish and olive oil. Personal targets — for potassium, phosphate, protein and fluid — should be set by your renal team based on your bloods.

Foods to prioritise

  • Vegetables, lower-potassium fruit and whole grains
  • Sensible portions of fish, eggs, chicken or tofu
  • Olive oil and unsalted nuts in small amounts

Foods to limit

  • Added salt and ultra-processed foods
  • Phosphate additives in processed meats and ready meals
  • Sugary and energy drinks

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 first signs of kidney problems?

Early CKD is usually silent. The first noticeable signs include persistent fatigue, foamy or bubbly urine (proteinuria), waking at night to pass urine (nocturia), ankle or eye swelling, itchy skin, and a rise in blood pressure. By the time symptoms are obvious, kidney function is often already reduced — which is why annual eGFR and urine ACR testing matters.

Does kidney pain mean kidney disease?

Usually not. Most chronic kidney disease (CKD) is painless. Loin (flank) pain is more often a kidney stone, urinary tract infection, or musculoskeletal — not CKD. Severe one-sided loin pain with fever needs urgent GP / A&E review.

Can I check my kidneys at home?

Partially. Home blood-pressure monitoring and dipstick urine tests for blood and protein are useful screens. They do not replace a GP eGFR (blood test) and urine ACR (albumin-creatinine ratio) — the two NHS tests that diagnose and stage CKD.

When should I see a GP about possible kidney problems?

Book an appointment if you have persistent foamy urine, ankle swelling, unexplained fatigue, blood in the urine, or known risk factors (diabetes, high blood pressure, family history, age over 60) and have not had an eGFR + ACR in the last 12 months.

What foods are good for kidney health?

A Mediterranean-style, mostly plant-based, reduced-salt diet is the most consistent evidence-based pattern for kidney health. Build meals around vegetables, lower-potassium fruit, whole grains, fish, eggs or tofu, beans and pulses in moderation, and olive oil.

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, NHS CKD pathway and BDA renal nutrition guidance.

Designed by a UK Consultant Nephrologist

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

Evidence-based by design

Plain-English explanations, NHS-aligned next steps, no scare tactics.

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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