A method for determining tissue insulin sensitivity in a human subject, characterized in that a) in a blood sample drawn from a human subject, the following laboratory parameters and concentrations of the following proteins in blood serum are measured: red blood cells, alanine aminotransferase (AlAT), C-peptide, sex hormone binding globulin ( SHBG), adiponectin, insulin-like growth factor binding protein-1 (IGFBP1); b) an insulin sensitivity index is determined on the basis of obtained results of measurements specified in a) using the following equation: Insulin sensitivity index = 11.5847 - RBC x 0.9622 - AlAT x 0.0308 - C-peptide x 1.0718 + SHBG x 0.0239 + Adiponectin x 0.0466 + IGFBP1 x 0.1206, wherein RBC is the value of red blood cells count measured in the sample using a method having 4-6 mln/μl reference interval for general population; AlAT is the value of alanine aminotransferase activity measured in the sample using a method having 5 - 50 U/l reference interval for general population; C-peptide is the value of C-peptide concentration measured using a method having 0.003 - 0.04 pmol/ml sensitivity and 0.26 - 2 pmol/ml reference interval for general population; SHBG is the value of the concentration of sex hormone-binding globulin measured using a method having 0.02 - 0.35 nmol/l sensitivity and 9 - 144 nmol/l reference interval for general population; Adiponectin is the value of adiponectin concentration measured using a method having 0.15 - 0.5 μg/ml sensitivity and 6 - 30 μg/ml reference interval for general population; IGFBP1 is the value of the concentration of insulin-like growth factor binding protein-1 measured using a method having 0.009 - 0.02 ng/ml sensitivity and 0.2 - 18 ng/ml reference interval for general population. a) in a blood sample drawn from a human subject, the following laboratory parameters and concentrations of the following proteins in blood serum are measured: red blood cells, alanine aminotransferase (AlAT), C-peptide, sex hormone binding globulin ( SHBG), adiponectin, insulin-like growth factor binding protein-1 (IGFBP1); b) an insulin sensitivity index is determined on the basis of obtained results of measurements specified in a) using the following equation: Insulin sensitivity index = 11.5847 - RBC x 0.9622 - AlAT x 0.0308 - C-peptide x 1.0718 + SHBG x 0.0239 + Adiponectin x 0.0466 + IGFBP1 x 0.1206, wherein RBC is the value of red blood cells count measured in the sample using a method having 4-6 mln/μl reference interval for general population; AlAT is the value of alanine aminotransferase activity measured in the sample using a method having 5 - 50 U/l reference interval for general population; C-peptide is the value of C-peptide concentration measured using a method having 0.003 - 0.04 pmol/ml sensitivity and 0.26 - 2 pmol/ml reference interval for general population; SHBG is the value of the concentration of sex hormone-binding globulin measured using a method having 0.02 - 0.35 nmol/l sensitivity and 9 - 144 nmol/l reference interval for general population; Adiponectin is the value of adiponectin concentration measured using a method having 0.15 - 0.5 μg/ml sensitivity and 6 - 30 μg/ml reference interval for general population; IGFBP1 is the value of the concentration of insulin-like growth factor binding protein-1 measured using a method having 0.009 - 0.02 ng/ml sensitivity and 0.2 - 18 ng/ml reference interval for general population. RBC is the value of red blood cells count measured in the sample using a method having 4-6 mln/μl reference interval for general population; AlAT is the value of alanine aminotransferase activity measured in the sample using a method having 5 - 50 U/l reference interval for general population; C-peptide is the value of C-peptide concentration measured using a method having 0.003 - 0.04 pmol/ml sensitivity and 0.26 - 2 pmol/ml reference interval for general population; SHBG is the value of the concentration of sex hormone-binding globulin measured using a method having 0.02 - 0.35 nmol/l sensitivity and 9 - 144 nmol/l reference interval for general population; Adiponectin is the value of adiponectin concentration measured using a method having 0.15 - 0.5 μg/ml sensitivity and 6 - 30 μg/ml reference interval for general population; IGFBP1 is the value of the concentration of insulin-like growth factor binding protein-1 measured using a method having 0.009 - 0.02 ng/ml sensitivity and 0.2 - 18 ng/ml reference interval for general population.