QUICKI: The Sensitive Measure of Insulin Response
A logarithmic approach that detects early changes in insulin sensitivity before they become obvious.
Who is this especially useful for?
- ✓You want to detect insulin sensitivity changes early
- ✓You're tracking progress on a lifestyle intervention
- ✓Your HOMA-IR is borderline and you want a more sensitive measure
- ✓You have fasting glucose and insulin from the same blood draw
QUICKI uses logarithms for better sensitivity to small changes — ideal for tracking progress.
HOMA-IR gets most of the attention when it comes to measuring insulin resistance. But there's another index using the same blood values that some researchers consider even more sensitive for detecting early changes: QUICKI.
QUICKI (Quantitative Insulin Sensitivity Check Index) takes a different mathematical approach to the same question: how well does your body respond to insulin? It was developed by researchers at the NIH in 2000 and has proven particularly useful for detecting subtle changes in insulin sensitivity.
How to Find These Numbers on Your Lab Report
You need two values from a fasting blood draw:
Fasting Glucose
Listed as "Glucose", "Fasting Glucose", or "FBG" — must be fasting (8-12 hours)
Fasting Insulin
Listed as "Insulin" or "Fasting Insulin" — must be specifically requested (not routine)
Our calculator accepts glucose in mg/dL or mmol/L, and insulin in μU/mL or pmol/L.
I have my numbers →What is QUICKI?
QUICKI stands for Quantitative Insulin Sensitivity Check Index. Unlike HOMA-IR (which measures resistance), QUICKI directly measures sensitivity — it tells you how responsive your cells are to insulin.
The index was developed by Dr. Michael Quon and colleagues at the National Institutes of Health. They found that using logarithms of glucose and insulin values created a more linear relationship with the gold-standard glucose clamp test.
Higher QUICKI = better insulin sensitivity. Lower QUICKI = more insulin resistance. This is the opposite direction of HOMA-IR.
The Formula
QUICKI = 1 ÷ [log₁₀(Insulin) + log₁₀(Glucose)]
Insulin in μU/mL, Glucose in mg/dL • Logarithms reduce impact of extreme values
Example Calculation
Glucose: 90 mg/dL
Insulin: 8 μU/mL
QUICKI = 1 ÷ [log(8) + log(90)] = 1 ÷ [0.903 + 1.954] = 1 ÷ 2.857 = 0.35
This falls in the normal range — healthy insulin sensitivity
Why Logarithms Make QUICKI More Sensitive
The logarithmic transformation in QUICKI reduces the impact of extreme values and creates a more linear relationship with true insulin sensitivity. This makes QUICKI particularly good at detecting early changes before glucose or insulin levels become obviously abnormal.
r=0.78
Correlation
With gold-standard clamp test
Katz et al., 2000
NIH
Developed
National Institutes of Health
2000
Better
Sensitivity
Than HOMA-IR for early detection
Muniyappa, 2008
The research behind QUICKI
QUICKI was developed by Dr. Michael Quon and colleagues at the National Institutes of Health. They validated it against the hyperinsulinemic-euglycemic clamp — the gold standard for measuring insulin sensitivity.
The correlation was excellent (r = 0.78), actually higher than HOMA-IR's correlation with the clamp (r = -0.69). This makes QUICKI especially valuable for research and longitudinal tracking.
Subsequent studies have confirmed QUICKI's utility for detecting early insulin sensitivity changes in non-diabetic populations — where it may show changes before HOMA-IR does.
Three Perspectives on QUICKI
Different health paradigms interpret these thresholds differently:
Standard Medical
Standard cutoffs. Below 0.30 indicates significant insulin resistance.
Research Consensus
Functional medicine practitioners aim for higher values to optimize metabolic health.
Metabolic Focus
Low QUICKI often accompanies elevated TG/HDL and other metabolic markers.
QUICKI vs HOMA-IR
Both use the same blood tests. What's different?
| Aspect | QUICKI | HOMA-IR |
|---|---|---|
| What it measures | Insulin sensitivity (higher = better) | Insulin resistance (higher = worse) |
| Scale direction | Higher is better | Lower is better |
| Mathematical approach | Uses logarithms | Simple ratio |
| Correlation with clamp | r = 0.78 (excellent) | r = -0.69 (good) |
| Best for detecting | Early, subtle changes | Moderate-to-severe IR |
Use both: HOMA-IR for conventional reference, QUICKI for sensitive tracking of changes.
Example QUICKI Calculations
| Category | Glucose | Insulin | QUICKI |
|---|---|---|---|
| Excellent | 85 mg/dL | 5 μU/mL | 0.39 |
| Normal | 90 mg/dL | 8 μU/mL | 0.35 |
| Borderline | 95 mg/dL | 14 μU/mL | 0.31 |
| Reduced | 105 mg/dL | 22 μU/mL | 0.28 |
How to Improve Your QUICKI
Low QUICKI indicates reduced insulin sensitivity. The good news: it's often reversible:
Diet
- →Reduce refined carbohydrates and sugars
- →Increase fiber intake
- →Consider time-restricted eating
- →Minimize processed foods
Lifestyle
- →Regular aerobic and resistance exercise
- →Prioritize sleep (7-9 hours)
- →Manage stress levels
- →Lose excess weight (especially visceral fat)
How Quickly Can QUICKI Improve?
Insulin sensitivity can improve within weeks of dietary and exercise changes. Most people see measurable QUICKI improvement within 2-4 months of consistent lifestyle intervention. QUICKI's logarithmic scale makes it particularly good at showing early progress.
Key Takeaways
- 1QUICKI measures insulin sensitivity — higher is better (opposite of HOMA-IR)
- 2Optimal QUICKI is above 0.40; below 0.30 indicates significant resistance
- 3QUICKI uses logarithms for better sensitivity to early changes
- 4Correlates more closely with gold-standard clamp test than HOMA-IR
- 5Uses same blood tests as HOMA-IR (fasting glucose + fasting insulin)
- 6Low QUICKI is typically reversible with diet, exercise, and lifestyle changes
Related Tools
QUICKI Calculator
Calculate your score now
HOMA-IR Calculator
Measure insulin resistance
HOMA-B Calculator
Beta cell function
TG/HDL Calculator
Metabolic health marker
References
- Katz A, et al. Quantitative insulin sensitivity check index: a simple, accurate method for assessing insulin sensitivity in humans. J Clin Endocrinol Metab. 2000;85(7):2402-2410. PMID: 10902785
- Chen H, Sullivan G, Quon MJ. Assessing the predictive accuracy of QUICKI as a surrogate index for insulin sensitivity using a calibration model. Diabetes. 2005;54(7):1914-1925. PMID: 15983190
- Hrebicek J, et al. Detection of insulin resistance by simple quantitative insulin sensitivity check index QUICKI for epidemiological assessment. J Clin Endocrinol Metab. 2002;87(1):144-147. PMID: 11788638
- Muniyappa R, et al. Current approaches for assessing insulin sensitivity and resistance in vivo. Am J Physiol Endocrinol Metab. 2008;294(1):E15-E26. PMID: 17957034
This article is for educational purposes only. QUICKI is a screening tool, not a diagnostic test. Always interpret results with your healthcare provider.