Fasting Insulin Resistance Test
Type 2 diabetes doesn't appear overnight. Years before your blood sugar rises, your body may already be struggling to use insulin effectively. This test catches that problem early, while you can still change course.
The Fasting Insulin Resistance Index (FIRI) measures how effectively your body uses insulin to control blood sugar. The test calculates your FIRI score using fasting glucose and fasting insulin levels.
A raised score indicates your pancreas is working harder than normal to keep blood sugar stable. This pattern increases your risk of type 2 diabetes, cardiovascular disease, and metabolic syndrome, but catching it early means you can take action before diabetes develops.
This test is particularly useful if you have:
- • A family history of type 2 diabetes
- • PCOS (insulin resistance is common)
- • Difficulty losing weight despite diet and exercise
- • Central obesity (weight carried around the middle)
- • Fatigue or energy crashes after meals
Unlike a standard glucose test, FIRI can detect metabolic problems while your blood sugar is still in the normal range. You may have heard of HOMA-IR, which is a similar calculation method.
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Fasting Insulin Resistance Test
£111.88Related blood tests
Common questions
Q.How long do I need to fast?
Fast for 8-12 hours before your blood draw. Water is fine. Morning appointments work best.
Q.My glucose test was normal - why do I need this?
Normal glucose with high insulin means your body is compensating. This test reveals the strain before glucose rises.
Q.What if my FIRI is elevated?
Our GP will discuss lifestyle modifications, further testing, or referral to an endocrinologist if needed.
