Research

Hormonal

Elevated levels of C18:0 sphingolipids (specifically ceramide) in skeletal muscle are associated with insulin resistance in humans, independent of body weight or obesity status.

If you are overweight or obese, your risk for insulin resistance is not determined by your weight alone. Some individuals with excess body fat maintain high insulin sensitivity, while others do not. This difference is linked to specific lipid levels (C18:0 sphingolipids) in your muscles. While you cannot easily measure this at home, the takeaway is that 'metabolically healthy obesity' exists, and metabolic health should be assessed independently of BMI.

GoodSupportsHIGH confidence
In muscle, insulin resistance was characterized by higher levels of C18:0 sphingolipids... Muscle C18:0 sphingolipids may play a role in insulin resistance independent of excess adiposity.
Katherine Tonks et al. · Obesity · 2016

Why this rating

High-quality observational design using hyperinsulinemic-euglycemic clamps (gold standard for insulin sensitivity) and matched cohorts, though cross-sectional.

Source

Skeletal muscle and plasma lipidomic signatures of insulin resistance and overweight/obesity in humans

Katherine Tonks et al. · Obesity · 2016

DOI 10.1002/oby.21448

cross_sectional · n=51Cited 179×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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