Circulating leptin: a marker of health in female students.

We studied the relationship between serum leptin concentration and lifestyle factors in female nursing students. Serum leptin was estimated by radioimmunoassay and the correlation between these concentrations with serum lipids, physical fitness and Health-promoting Lifestyle Profile score was investigated. A total of 247 students took part in the study: mean age, 19.0 +/- 2.0 years; mean body mass index (BMI), 21.7 +/- 2.9 kg/m2; and mean serum leptin concentration, 10.8 +/- 11.5 ng/ml. Serum leptin was positively correlated with BMI, systolic and diastolic blood pressure, total cholesterol and serum triglyceride. Serum leptin level concentration inversely correlated with physical fitness score and lifestyle score. When the subjects were grouped according to BMI, the high-BMI group (BMI: > or = 24 kg/m2; n = 40) showed significantly lower fitness and lifestyle scores than the low-BMI group (BMI < or = 20 kg/m2; n = 70). Higher leptin, blood pressure, total cholesterol and triglyceride were seen in high-BMI compared with low-BMI subjects. We suggest that leptin is a useful marker for monitoring good health and may be useful as a motivational aid towards achieving and maintaining a healthy lifestyle.