The Visceral Adiposity Index (VAI) is a novel sex-specific index that combines waist circumference (WC), body mass index (BMI), triglycerides (TG), and high-density lipoprotein (HDL) cholesterol to indirectly assess visceral fat function. It was developed and validated in a study involving 315 nonobese healthy subjects and 1,498 primary care patients. The VAI showed significant associations with metabolic syndrome components and was independently linked to cardiovascular and cerebrovascular events. It also demonstrated a strong inverse correlation with insulin sensitivity, as measured by euglycemic-hyperinsulinemic clamp, in a subgroup of patients. Unlike WC and BMI, VAI was not correlated with these measures. The study concluded that VAI is a valuable indicator of visceral adipose function and insulin sensitivity, with increased levels strongly associated with cardiometabolic risk. VAI outperformed traditional parameters like WC, BMI, and TG-to-HDL ratio in predicting cardiovascular and cerebrovascular events. The index includes both physical and metabolic parameters, potentially reflecting non-classical risk factors such as altered adipocytokine production and lipolysis. VAI may be a useful tool for assessing cardiometabolic risk associated with visceral obesity in clinical practice and population studies.The Visceral Adiposity Index (VAI) is a novel sex-specific index that combines waist circumference (WC), body mass index (BMI), triglycerides (TG), and high-density lipoprotein (HDL) cholesterol to indirectly assess visceral fat function. It was developed and validated in a study involving 315 nonobese healthy subjects and 1,498 primary care patients. The VAI showed significant associations with metabolic syndrome components and was independently linked to cardiovascular and cerebrovascular events. It also demonstrated a strong inverse correlation with insulin sensitivity, as measured by euglycemic-hyperinsulinemic clamp, in a subgroup of patients. Unlike WC and BMI, VAI was not correlated with these measures. The study concluded that VAI is a valuable indicator of visceral adipose function and insulin sensitivity, with increased levels strongly associated with cardiometabolic risk. VAI outperformed traditional parameters like WC, BMI, and TG-to-HDL ratio in predicting cardiovascular and cerebrovascular events. The index includes both physical and metabolic parameters, potentially reflecting non-classical risk factors such as altered adipocytokine production and lipolysis. VAI may be a useful tool for assessing cardiometabolic risk associated with visceral obesity in clinical practice and population studies.