Metabolic syndrome (MetS) screener for type-2 diabetes, heart disease, and stroke risk, using NCEP ATP III criteria.
Four tabs: five MetS criteria check (waist circumference, triglycerides, HDL, BP, fasting glucose), continuous severity score, 10-year heart-disease risk, and personalized intervention targets per failed criterion.
Disclaimer: A screen, not a diagnosis. Confirm with lab work and an internal-medicine physician.
Calculator information
📋 How to use this calculator
- Select your sex, since the waist circumference threshold differs: men >=40 in (102 cm), women >=35 in (88 cm) under the NCEP ATP III criteria.
- Enter waist circumference in inches or centimeters, measured midway between the lower rib and the iliac crest after a normal exhale.
- Enter triglycerides (mg/dL) and HDL cholesterol (mg/dL) from a fasting lipid panel (9-12 hours fasting).
- Enter systolic and diastolic blood pressure (mmHg) as the average of two readings taken 5 minutes apart.
- Enter fasting blood glucose (mg/dL); if you already have a type 2 diabetes diagnosis or take glucose-lowering medication, still check the criterion as positive.
- Review results on the continuous severity score tab to monitor subtle changes over time even before you meet 3 criteria.
- Compare with the 10-year cardiovascular risk tab and apply the per-criterion intervention targets it suggests.
🧮 NCEP ATP III Criteria (2005 Revision) for Metabolic Syndrome
MetS = 1 if number of positive criteria >= 3 out of 5
- Waist circumference: men >=40 in (102 cm), women >=35 in (88 cm) for general U.S. population; lower cutoffs (men >=90 cm, women >=80 cm) for individuals of South/East Asian descent
- Triglycerides >=150 mg/dL or on lipid-lowering therapy
- HDL <40 mg/dL in men or <50 mg/dL in women
- Blood pressure >=130/85 mmHg or on antihypertensive therapy
- Fasting glucose >=100 mg/dL or established type 2 diabetes
The continuous severity score (MetS-Z) uses a z-score regression of the 5 components calibrated by race and sex (Gurka 2014); a score >=1.0 corresponds to roughly a 4-6x increase in diabetes risk.
💡 Worked example: 45-year-old man with central obesity
Given:- Waist circumference 41 in (104 cm)
- Triglycerides 180 mg/dL
- HDL 38 mg/dL
- Blood pressure 135/88 mmHg
- Fasting glucose 108 mg/dL
Steps:- Waist 41 in >= 40 in threshold for men (positive).
- Triglycerides 180 >= 150 mg/dL (positive).
- HDL 38 < 40 mg/dL for men (positive).
- Blood pressure 135/88 >= 130/85 mmHg (positive).
- Fasting glucose 108 >= 100 mg/dL (positive).
- Total positive criteria = 5 of 5, exceeding the threshold of 3.
Result: Metabolic syndrome diagnosed (5/5 criteria). The 10-year risk of type 2 diabetes is roughly 5x higher and cardiovascular disease risk roughly 2x higher than without MetS.
❓ Frequently asked questions
What is the difference between the NCEP ATP III and IDF criteria?
NCEP ATP III requires any 3 of 5 equally weighted criteria, while IDF requires central obesity (waist circumference) as a mandatory criterion plus 2 of the remaining 4. IDF uses stricter ethnicity-specific waist cutoffs (men of Asian descent >=90 cm, women >=80 cm). This calculator defaults to NCEP ATP III (2005 revision) because it is the most widely used standard in U.S. clinical practice and research.
Can lean people develop metabolic syndrome?
Yes. The phenomenon is sometimes called TOFI (Thin Outside, Fat Inside): normal BMI but high visceral fat, insulin resistance, and dyslipidemia. Population studies find that roughly 15-20% of individuals with BMI <25 still meet MetS criteria. That is why waist circumference is more predictive than BMI alone for screening.
Is metabolic syndrome reversible?
Yes. MetS is reversible through 5-10% weight loss from baseline, 150 minutes/week of moderate-intensity physical activity, a diet low in refined carbohydrates, and adequate sleep. The Diabetes Prevention Program showed that lifestyle intervention reduced diabetes incidence by 58% in prediabetic patients. Metformin can be considered if fasting glucose is >=110 mg/dL.
How often should it be rechecked?
For initial screening, annual checks are reasonable if you are 40+ or have a family history of diabetes or heart disease. Once MetS is diagnosed, recheck every 3-6 months to monitor response to intervention. A minimum workup includes waist circumference, blood pressure, a full lipid panel, and fasting glucose or HbA1c.
Does this calculator replace a physician's diagnosis?
No. This is a screening tool based on published criteria, not a clinical diagnosis. A positive result should be confirmed by a clinician with additional tests such as HbA1c, LDL cholesterol, uric acid, and assessment of comorbidities. A MetS diagnosis is only meaningful when paired with a structured intervention plan.
📚 Sources & references
Last updated: May 11, 2026