Insulin sensitivity

Insulin sensitivity is the degree to which peripheral tissues — primarily skeletal muscle, adipose, and liver — respond to a given concentration of circulating insulin. The opposite end of the spectrum is insulin resistance, the hallmark metabolic abnormality in type 2 diabetes and the metabolic syndrome.

Measurement

• Fasting insulin and HOMA-IR · static readout, easy to compute
• Hyperinsulinemic-euglycemic clamp · gold-standard but invasive
• Oral glucose tolerance test (OGTT) · area-under-curve indices

Relevance to research peptides

• MOTS-c · preclinical literature reports restoration of insulin sensitivity in diet-induced obese mice (Lee et al., Cell Metab 2015; PMID 25738459)
• Semaglutide, Tirzepatide, Retatrutide · incretin agonists with documented effects on glycemic control in published clinical trials
• NAD+ · cellular-bioenergetics framing relevant to insulin-signaling efficiency

See also

• GLP-1_receptor
• AMPK