Cardiometabolic index calculator

The formula

CMI is the waist-to-height ratio multiplied by the ratio of triglycerides to HDL cholesterol (Wakabayashi 2015). The same authors spell out the units: waist and height in centimeters, triglycerides and HDL cholesterol in mg/dL (Wakabayashi 2023). Waist and height only need to be in the same unit, so inches work too. If your lab reports mmol/L, we first convert: triglycerides times 88.57 and HDL cholesterol times 38.67.

For example, a waist of 90 cm, a height of 170 cm, triglycerides of 150 mg/dL and HDL of 50 mg/dL give (90 ÷ 170) × (150 ÷ 50) = 0.53 × 3.00 = 1.59.

A triglyceride-to-HDL ratio worked out from mmol/L numbers is on a different scale, about 0.44 times the mg/dL ratio, so do not compare it with the cutoffs below. The calculator converts for you. For the plain ratio on its own, see the triglyceride to HDL ratio calculator.

What the study found

The 2015 study looked at 10,196 Japanese women and men at workplace health checkups. In both women and men, hemoglobin A1c was higher in the top quarter of CMI values than in the other three quarters. Using the cutoffs below, people with a high CMI had higher odds of high blood sugar and of diabetes than people without a high CMI (Wakabayashi 2015):

For high blood sugar, the odds ratios were 6.98 (4.68 to 10.42) in women and 4.42 (3.66 to 5.35) in men. The authors concluded that CMI, which reflects both body fat and blood fats, may be a useful new index for telling apart people with diabetes (Wakabayashi 2015).

Please read these numbers with care:

• The cutoffs were picked in the same group of Japanese workers they describe, using ROC analysis. They have not been set as a screening rule, and no US guideline uses CMI.
• An odds ratio compares groups. It is not your chance of having diabetes.
• The abstract does not say whether a value exactly at a cutoff counts as high; we count it as at or above.

If you are worried about diabetes

CMI cannot show whether you have diabetes or prediabetes. A blood test such as the A1C test can (CDC). To see whether you should get tested, take the type 2 diabetes risk test, and read what prediabetes means.

How CMI relates to other tools on this site

CMI is built from two numbers you can look at on their own. The waist-to-height ratio calculator places your waist-to-height ratio in the NICE bands. The atherogenic index of plasma uses the same triglyceride and HDL numbers, as the log of their ratio in mmol/L. CMI multiplies the two ratios together, so its value and its cutoffs differ from both.

Other research indexes also mix body size and blood fats. The lipid accumulation product pairs waist size with triglycerides, and the visceral adiposity index adds BMI and HDL. The hypertriglyceridemic waist check looks at waist and triglycerides against two cut points from a study in men. The metabolic syndrome criteria checker uses set cutoffs for waist, triglycerides, HDL, blood pressure and blood sugar. None of these diagnoses a disease.

Getting the right numbers

Use triglycerides and HDL cholesterol from the same cholesterol test. You may be asked to fast for 9 to 12 hours before it (MedlinePlus). For measuring your waist, see how to measure on the waist-to-height ratio page. If you compare CMI over time, measure and test the same way each time.