Essential hypertension has been shown by various studies to be an insulin-resistant state. However, most of these studies have included obese and elderly patients. We were interested to know the extent of insulin resistance in a group of young, non-obese patients with hypertension. A total of 59 male patients with essential hypertension and 31 controls matched for age, sex and body mass index were studied. All the subjects were under 35 years old and had a body mass index of less than 27 kg/m2. Our results showed that such patients with hypertension had significantly higher fasting insulin, total insulin after glucose challenge, insulin/glucose ratio and higher triglycerides than the control subjects.