Kidney Function Test (KFT): How to Read Your Report

You've got a lab printout in your hand, a row of numbers with tiny arrows next to them, and one big question: is something wrong with my kidneys? If your KFT (Kidney Function Test) has an "H" or a red flag beside creatinine or urea, it's natural to feel anxious. Take a breath — one number rarely tells the whole story.

This guide walks you through every line of a typical Indian KFT report in plain language: what each value means, what the normal ranges are, and what usually pushes them up or down. It's written and medically reviewed by an Ayurvedic doctor so you leave understanding your report — not more scared of it.

Key Takeaways

• A KFT (Kidney Function Test), also called RFT (Renal Function Test), is a blood panel — usually paired with a urine test — that checks how well your kidneys are filtering waste.
• The core numbers are serum creatinine, blood urea / BUN, eGFR, and uric acid, plus electrolytes like sodium and potassium.
• eGFR is the single best snapshot of kidney function; creatinine and urea support the picture.
• One high reading is not a diagnosis. Trends over time and your symptoms matter far more than a single report.
• Diet, dehydration, protein intake, medicines and even a heavy gym session can nudge these numbers — so context is everything.

What Is a Kidney Function Test (KFT)?

A Kidney Function Test is a group of blood (and often urine) tests that together estimate how efficiently your two kidneys are clearing waste products from your blood. Your kidneys filter around 180 litres of blood a day, holding on to what your body needs and sending the rest out as urine. When filtering slows down, waste products like creatinine and urea start to build up — and that shows up on the report.

Doctors order a KFT to screen people with diabetes or high blood pressure, to check before or during certain medicines, or simply to investigate symptoms like swelling, foamy urine, fatigue or changes in urination. In most Indian labs the panel is printed as "KFT" or "RFT" and lists 6–10 values in a single column.

The Main Numbers on Your KFT Report

Here's what each common line means, with the general adult reference ranges. Always compare against the range printed on your own lab's report — ranges vary slightly by lab, method and machine.

Serum Creatinine

Creatinine is a waste product your muscles make every day. Healthy kidneys clear it steadily, so the blood level stays fairly stable — which is exactly why it's such a useful marker. A higher-than-range creatinine can signal reduced filtering, but it also rises temporarily with dehydration, a very high non-veg/protein diet, intense exercise, or certain supplements. Muscular people naturally sit a little higher; older adults and those with less muscle mass, a little lower. For a deeper look, see our guide on the causes of high creatinine.

Blood Urea and BUN

Urea forms when your body breaks down protein. Blood urea and BUN move up with a heavy protein diet, dehydration, fever, or bleeding in the gut — not only with kidney issues. That's why doctors read urea alongside creatinine rather than on its own. If your urea is flagged, our detailed explainer on high blood urea (BUN) breaks down the common reasons.

eGFR — the Number That Matters Most

eGFR (estimated Glomerular Filtration Rate) is calculated from your creatinine, age, and sex. It estimates how many millilitres of blood your kidneys filter per minute, and it's the value doctors lean on most. As a rough guide, according to the National Kidney Foundation:

• 90+ — normal kidney function (if no other signs of damage)
• 60–89 — mildly reduced; often normal for age, worth monitoring
• Below 60 for 3 months or more — may indicate chronic kidney disease and needs a doctor's review
• Below 15 — severely reduced function

A single low eGFR isn't a verdict — dehydration and lab timing can affect it. What counts is whether it stays low across repeat tests. To understand how eGFR and creatinine relate, read eGFR vs creatinine.

Uric Acid

High uric acid is linked to gout and, over time, can add strain to the kidneys. It rises with purine-rich foods (organ meats, some seafood, excess alcohol) and low water intake. It's often included in the KFT because urate is filtered by the kidneys too.

Electrolytes: Sodium and Potassium

These reflect the kidney's role in balancing fluids and minerals. Potassium especially is watched closely in people with reduced kidney function, because unhealthy kidneys can struggle to clear it. If yours are flagged, don't self-correct with diet changes — ask your doctor first, as both too-high and too-low potassium need proper guidance.

The Urine Side of the Report

A KFT is often paired with a urinalysis. Two things doctors look for:

Protein / albumin in urine. Healthy kidneys keep protein in the blood. Protein leaking into urine (proteinuria or albuminuria) can be an early sign that the filters are stressed. Learn more in protein in urine: causes and signs, and note that persistent foamy urine can be a visible clue.

Urine ACR (albumin-to-creatinine ratio). A sensitive test that catches small amounts of albumin early — useful for people with diabetes or high BP.

What Can Push Your Numbers Up (That Isn't Kidney Disease)

Before you assume the worst, know that these common factors can raise KFT values temporarily:

• Dehydration — the most common reason for a mildly high creatinine and urea in Indian summers.
• A high-protein or heavy non-veg meal the day before the test.
• Intense workouts or heavy physical labour just before the blood draw.
• Certain medicines and supplements — some painkillers (NSAIDs), specific antibiotics, and creatine supplements.
• Fasting status, fever, or recent illness.

This is why one flagged report should be repeated and interpreted by a doctor — ideally with a look at the trend, not a single point.

The Ayurvedic Perspective on Kidney Support

In Ayurveda, the kidneys and the urinary system fall largely under mutravaha srotas (the channels carrying urine) and are closely tied to apana vata and the body's fluid balance. Classical texts describe herbs traditionally used to support healthy urine flow and normal fluid balance, which is the reasoning behind their long use in kidney-and-urinary wellness formulas:

• Punarnava (Boerhavia diffusa) — traditionally used to support healthy fluid balance and normal urine flow. See Punarnava for kidney health.
• Gokshura (Tribulus terrestris) — a classical mutrala (diuretic-supporting) herb used for urinary comfort and flow. See Gokshura benefits.
• Varuna (Crataeva nurvala) — traditionally used in Ayurveda for the urinary tract.

Important and non-negotiable: Ayurvedic herbs are used to support healthy kidney function as part of an overall wellness routine — they are not a substitute for medical treatment, and they do not cure, treat or reverse kidney disease. If you already have a kidney condition, some herbs (and their potassium content) may not be suitable, so always clear them with your doctor first.

Practical Steps to Support Healthy Kidneys

Small, consistent habits matter more than any single dramatic change:

• Hydrate sensibly. For most healthy adults, pale-yellow urine is a good target. Don't force-drink litres if your doctor has restricted fluids. See how much water for healthy kidneys.
• Go easy on salt. Aim to cut back on papad, pickle, namkeen and packaged snacks — high sodium strains blood pressure and kidneys.
• Moderate protein, don't overdo it. You don't need to give up dal or paneer; just avoid piling on protein powders or huge non-veg portions without guidance.
• Control the big two: sugar and blood pressure. Diabetes and hypertension are the leading drivers of kidney trouble in India — see the diabetes–kidney connection.
• Be careful with painkillers. Frequent, unsupervised NSAID use can hurt kidneys over time.
• Don't smoke, limit alcohol, and stay active.

When to See a Doctor

Book a proper consultation — don't just re-test at home — if you notice:

• eGFR staying below 60, or creatinine climbing across repeated reports
• Persistent swelling in the feet, ankles or around the eyes (swelling and the kidney link)
• Foamy or bloody urine, or a big change in how much you urinate
• Ongoing fatigue, nausea, loss of appetite or breathlessness
• You have diabetes or high BP and haven't had a KFT in over a year

A nephrologist can interpret your full picture — blood, urine, history and imaging — and that is the only reliable way to know what your numbers mean for you.

How CreatiCare Fits

If your goal is to support healthy creatinine levels and overall kidney wellness alongside good diet and hydration, CreatiCare™ Creatinine Capsules is our Ayurvedic formula built around traditionally-used kidney-support herbs like Punarnava and Gokshura. It's designed as part of a daily wellness routine — not as a replacement for your doctor's advice or any prescribed medicine. If you have a diagnosed kidney condition or take regular medication, please check with your physician before starting it.

Frequently Asked Questions

What is the difference between KFT and RFT? None — KFT (Kidney Function Test) and RFT (Renal Function Test) are two names for the same blood panel that checks creatinine, urea, eGFR and related values.

Do I need to fast before a KFT? For a standalone KFT, fasting is usually not required, but many labs run it with other tests (like a lipid or sugar panel) that do need fasting. Follow the instructions your lab or doctor gives you.

Is a single high creatinine reading serious? Not necessarily. Dehydration, a heavy protein meal or intense exercise can raise it temporarily. Doctors usually repeat the test and look at the trend along with your eGFR and symptoms before drawing conclusions.

Which is the most important value on the report? eGFR gives the best overall estimate of kidney function, but it's read together with creatinine, urea and your urine protein for a complete picture.

Can diet and lifestyle really change my KFT numbers? Staying well hydrated, moderating salt and protein, and controlling blood sugar and blood pressure can all influence these values and support kidney health. Any change should be guided by your doctor, especially if you already have a kidney condition.

How often should I get a KFT done? If you're healthy, whenever your doctor advises. If you have diabetes, high BP or a family history of kidney disease, an annual (or more frequent) KFT is commonly recommended — ask your physician for a schedule that fits you.

Written & medically reviewed by Dr. Istuti, BAMS

Dr. Istuti is an in-house Ayurvedic physician (Bachelor of Ayurvedic Medicine and Surgery) at Cureayu, with a special interest in kidney and urinary wellness. She reviews every health article for accuracy, safety, and compliance with Ayurvedic and modern medical guidance.

Medically reviewed on 30 July 2026.

Disclaimer

This content is for educational purposes and is not a substitute for professional medical advice. Consult a qualified physician before starting any supplement, especially if you have a kidney/prostate condition or take medication.

Sources

• National Kidney Foundation — Estimated Glomerular Filtration Rate (eGFR): https://www.kidney.org/atoz/content/gfr
• NIDDK — Kidney Tests: https://www.niddk.nih.gov/health-information/kidney-disease/kidney-tests
• MedlinePlus — Kidney Function Tests: https://medlineplus.gov/lab-tests/kidney-function-tests/
• Ministry of AYUSH, Government of India: https://www.ayush.gov.in/