Your kidneys are two small organs — each about the size of your fist — but they do an enormous amount of work. Every single day, they filter around 200 litres of blood, removing waste products and excess fluid that would otherwise build up and become toxic.

Think of them as your body's filtration and control centre. They do six main jobs:

Chronic Kidney Disease (CKD) means your kidneys have been damaged and can't filter blood as well as they should. The word chronic just means it develops slowly over time and doesn't go away.

Healthy kidneys contain around one million tiny filtering units called nephrons. In CKD, nephrons get damaged and stop working. The remaining healthy nephrons work harder to compensate — but over time, they too can become overworked and damaged.

Because the kidneys adapt so well, you often don't notice any symptoms until 50–60% of kidney function is already lost. This is why CKD is sometimes called a "silent" disease — and why blood tests are so important.

eGFR stands for Estimated Glomerular Filtration Rate — and it's the key number used to measure how well your kidneys are working.

It estimates how many millilitres of blood your kidneys can clean per minute, adjusted for your body size. A healthy young adult has an eGFR of around 90–120 mL/min/1.73m².

eGFR is calculated from a blood test measuring creatinine — a waste product your muscles naturally produce. If creatinine is high, it means the kidneys aren't clearing it efficiently, so eGFR is low.

What you eat directly affects how hard your kidneys have to work. With CKD, kidneys struggle to process and excrete certain minerals — so managing your diet can genuinely slow the progression of the disease.

CKD is often symptom-free until the later stages. When symptoms do appear, they're caused by the build-up of waste products and fluid, and the knock-on effects on other body systems.

There is no cure for CKD, but the right management can significantly slow its progression and keep you feeling better for longer.

• Control blood pressure — aim for below 130/80 mmHg. ACE inhibitors and ARBs both treat blood pressure and protect kidneys.
• Manage blood sugar — if you have diabetes, tight glucose control is one of the most powerful ways to protect your kidneys.
• Follow a kidney-friendly diet — work with a renal dietitian to find the right balance of protein, potassium, phosphate and fluid.
• Stay active — regular gentle exercise (walking, cycling, swimming) supports cardiovascular health and helps with fatigue.
• Avoid NSAIDs — ibuprofen, naproxen and similar anti-inflammatories are harmful to kidneys. Use paracetamol instead.
• Stay hydrated — unless you have a fluid restriction, drinking enough water helps kidneys flush waste products.
• Don't smoke — smoking accelerates kidney disease progression and greatly increases cardiovascular risk.
• Take your medications — phosphate binders, EPO injections, vitamin D supplements and blood pressure medications all play important roles.
• Attend all appointments — regular blood tests allow your team to spot changes early and adjust treatment.