Leptin concentrations in relation to overall adiposity and regional body fat distribution in Mexican Americans

Leptin, the product of the human OB gene is increased in obese individuals suggesting resistance to its effect. However, there is variability in leptin levels at each level of body mass index suggesting that genetic and environmental factors other than overall adiposity may regulate leptin concentrations. Moreover, the relation of leptin to various adipose depots may differ. Upper body (or central adiposity) is more metabolically active than peripheral adiposity.

We examined the relation of serum leptin levels to body fat distribution in 147 non-diabetic subjects from the San Antonio Heart Study.

Leptin concentrations in men were significantly correlated with body mass index (BMI) (r = 0.741), waist-to-hip ratio (WHR) (r = 0.567), waist circumference (r = 0.840), hips circumference (r = 0.842) triceps skinfold (r = 0.520) and subscapular skinfold (r = 0.668) but not with subscapular to triceps skinfold (r = 0.185). Leptin concentrations in women were significantly correlated with BMI (r = 0.814), WHR (r = 0.377), waist circumference (r = 0.718), hips circumference (r = 0.779), subscapular skinfolds (r = 0.636) and triceps skinfolds (r = 0.587) but not with the ratio of subscapular to triceps skinfolds (r = 0.184) in women.

Since the associations of leptin with body mass index (a surrogate for overall adiposity), waist circumference (a surrogate for upper body) and hips circumference (a surrogate for lower body adiposity) are similar, we conclude that leptin concentrations are associated with all adipose tissue depots and not disproportionately with upper body or central adiposity.