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Important
This article is general information about chronic kidney disease, not medical advice or a recommendation, and it does not replace assessment by a qualified professional. Always see an appropriate healthcare professional about your own symptoms, diagnosis and treatment, including before starting, stopping or changing any medication or supplement. The treatment summaries here are for general understanding only and are not prescribing guidance.
Key points
- Chronic kidney disease (CKD) is a long-term reduction in how well the kidneys work, usually progressing slowly and silently.
- The two leading causes worldwide are diabetes and high blood pressure, both rooted in poor metabolic health.
- It is detected with simple blood and urine tests, often before any symptoms appear.
- Controlling blood sugar and blood pressure, and improving metabolic health, are central to slowing and potentially improving it.
- Medications are sometimes used alongside lifestyle improvement.
What it is
Chronic kidney disease is a long-standing reduction in kidney function. The kidneys filter waste and excess fluid from the blood, balance salts and minerals, control blood pressure, and support red-blood-cell and bone health. In CKD this filtering capacity declines, usually gradually over years. It is graded in stages (1 to 5) based on how well the kidneys filter and how much protein leaks into the urine.
CKD is common, particularly with age and with diabetes and high blood pressure, and much of it is preventable or can be slowed.
What causes it, and who is at risk
The two commonest causes globally are diabetes and high blood pressure, both closely tied to metabolic health. Other causes include certain kidney and urinary diseases, recurrent infections or obstruction, some medications, and inherited conditions. Risk factors therefore include diabetes, high blood pressure, obesity, insulin resistance, cardiovascular disease, increasing age, family history, and certain ethnic backgrounds. Many people have more than one risk factor.
Symptoms and signs
Early CKD usually causes no symptoms and is found on testing, though poor metabolic health can cause symptoms such as fatigue, difficulty losing weight, high blood pressure and skin tags.
Because early disease is silent, testing those who are at risk of CKD is the key to catching it early.
How it is diagnosed
CKD is detected with two simple tests: a blood test estimating kidney filtering (the eGFR) and a urine test for protein (the albumin-to-creatinine ratio, or ACR). These are repeated to confirm that the change is persistent (over three months). Further tests may be done to look for other causes. People with diabetes, high blood pressure or other risk factors are typically screened for CKD at least annually, which helps with early detection.
The metabolic health perspective
The kidneys are highly vascular organs (many blood vessels), and they are damaged by the same processes that harm blood vessels elsewhere. High blood sugar injures the kidneys’ delicate filtering units over time (diabetic kidney disease), and high blood pressure, itself often driven by insulin resistance, adds mechanical strain. Visceral fat (fat inside the belly) releases inflammatory signals that add to the damage, and persistently high insulin itself is thought to affect how the kidneys handle salt and pressure. This is why CKD so often accompanies diabetes, hypertension and the wider pattern of poor metabolic health, and why metabolic health is one of the main levers for protecting the kidneys.
The main causes are largely modifiable. Good control of blood sugar and blood pressure, weight loss where relevant, and improving metabolic health slow the decline and reduce the chance of progression, and several modern medicines protect the kidneys directly. Catching CKD early, before symptoms, gives the best chance of preserving function.
Treatment and management
The aims are to treat the underlying cause, slow progression, protect the heart (cardiovascular disease is the main risk in CKD), and manage the consequences. The approach combines lifestyle change and sometimes medication, under medical care.
Lifestyle and the Health Foundations
Nutrition
In earlier CKD, particularly if there is also insulin resistance, the same principles that support metabolic health generally apply: build meals around sources of protein, fill most of the rest of the plate with non-starchy vegetables, add natural fats for flavour, and treat starchy carbohydrate as an optional extra rather than a fixed portion. This helps control blood sugar and blood pressure. In more severe CKD the approach changes: protein, potassium, phosphate and salt intake may all need individual adjustment, and a higher-protein approach is not automatically appropriate. Severe CKD is usually managed by kidney specialists.
Movement and weight
Aim for at least 150 minutes a week of moderate activity, plus resistance exercise two to three times a week if able. Regular activity and losing excess weight support blood pressure and metabolic health.
Blood pressure, smoking and alcohol
Controlling blood pressure, not smoking, and moderating alcohol all protect the kidneys. Good sleep (seven to nine hours a night) supports healthy blood pressure and blood sugar, both relevant to kidney protection.
Other non-pharmaceutical options
People with CKD must be cautious with supplements, as some (and certain "natural" remedies) can harm the kidneys or accumulate to harmful levels. Correcting genuine deficiencies and avoiding substances that can damage the kidneys should be done under medical guidance. Always check supplements and over-the-counter medicines (including anti-inflammatory painkillers, which can harm the kidneys) with a pharmacist or clinician.
Medical and pharmaceutical treatments
- Blood-pressure medicines that also protect the kidneys (ACE inhibitors or ARBs) are often used, especially when protein is leaking.
- SGLT2 inhibitors (such as dapagliflozin or empagliflozin) protect the kidneys and heart in many people with CKD, whether or not they have diabetes, and current UK guidance supports their use on this basis.
- For people with diabetes good sugar control is essential.
- In advanced (stage 5) disease, dialysis or a kidney transplant may eventually be needed.
These decisions should be made with a clinician; the above is a summary for understanding, not prescribing guidance.
Complications and outlook
CKD raises the risk of cardiovascular disease (the most common cause of harm in CKD), and advanced disease can lead to kidney failure requiring dialysis or transplant, as well as anaemia and bone problems. The outlook depends heavily on the stage at which it is caught and on control of the causes: many people with early CKD never progress to serious disease, especially with good blood-sugar and blood-pressure control and modern kidney-protective medicines.
When to see a doctor
- If you have diabetes, high blood pressure, or other risk factors, attend regular kidney checks (blood and urine tests).
- Check any new supplement or painkiller with a pharmacist (or clinician) if you have CKD, as some can harm the kidneys.
Summary
- Chronic kidney disease is a long-term, usually silent decline in kidney function.
- Its leading causes, diabetes and high blood pressure, are rooted in metabolic health.
- Simple blood and urine tests detect it early, often before symptoms.
- Controlling blood sugar and blood pressure, and improving metabolic health, slow it; modern medicines protect the kidneys.
- Early detection greatly improves the outlook, and avoiding kidney-harming substances matters.
Health Shelf, healthshelf.org · Dr Campbell Murdoch, GP, UK · Reviewed August 2026
This is general information, not medical advice. Always speak to a qualified healthcare professional about your own symptoms and treatment, including before changing any medication.