
This paper, written by european researchers, describes a newer way to estimate insulin sensitivity (or it’s unhealthy opposite, insulin resistance) using commonly obtained lab values. Here’s the equation they came up with:
The novel formula for SPISE was computed as follows: SPISE = 600 X HDL-0.185/(TG0.2 x BMI1.338, with fasting HDL-C (mg/dL), fasting TG concentrations (mg/dL), and BMI (kg/m2)Paulmichl K, Hatunic M, Højlund K, Jotic A, Krebs M, Mitrakou A, et al. Modification and Validation of the Triglyceride-to-HDL Cholesterol Ratio as a Surrogate of Insulin Sensitivity in White Juveniles and Adults without Diabetes Mellitus: The Single Point Insulin Sensitivity Estimator (SPISE). Clin Chem [Internet]. Clinical Chemistry; 2016 Sep 1 [cited 2018 Oct 24];62(9):1211–9
This is important because other methods are either less accurate (a common method is to compute TG/HDL, with a cutoff of below 2.0 for insulin sensitivity) or much more intensive (ingesting glucose in a lab and monitoring its disappearance and measured insulin levels).
There’s a breakdown in the article of the common methods and their sensitivities and specificities.
The cutoff for this calculation is 6.61. A value higher than this means “insulin sensitive,” a value lower than this means “insulin resistant”
This calculation, the Single Point Insulin Sensitivity Estimator (SPISE) was used in this paper to demonstrate that individuals who progressed to pre-diabetes or diabetes showed impaired insulin sensitivity much earlier than their diagnosis, maybe up to 20 years:

This calculation may be able to help patients and doctors see progress as they engage in dietary approaches to prevent or reverse diabetes. I created a spreadsheet for myself with the equation and am happy to punch in values for people, or share the spreadsheet.
The reason these numbers put together in this way give a measure of insulin sensitivity is beyond the scope of this post, however, it’s known that the biochemical adjustments that happen in the setting of a body overwhelmed with insulin that cannot do its job versus one that isn’t have an impact on measured HDL and triglycerides.
Check My Work Please
I am not an endocrinologist or a basic scientist, so I’d welcome anyone checking my work on this and letting me know if this is something useful clinically.