The study investigated whether girls were intrinsically more insulin resistant than boys in a community-based study that included 307 healthy children from school entry at age 5 years.

Girls had slightly higher body-mass index and greater waist circumference corrected for height than boys did, the authors report, and they had gained significantly more excess weight since birth than boys had.

Neither physical activity nor weight-adjusted resting energy expenditure correlated with insulin resistance in boys or girls, the researchers note, though boys were more physically active and had higher resting energy expenditure levels than girls.

Fasting insulin concentrations and triglycerides were significantly higher in girls, the investigators report, and HDL cholesterol and sex hormone binding globulin (SHBG) were lower.

Dr. Wilkin stated that, "Girls are intrinsically more insulin resistant than boys, exposing them in childhood to a greater risk of metabolic disturbances such as diabetes," and they must pay even more attention to diet and exercise - but typically they don't!"

The investigators' paper is subtitled The Programming Hypotheses Revisited. "We believe [the gender difference] has fundamental importance to species survival and are this month submitting a paper on a new hypothesis relating to the importance of gender difference," Dr. Wilkin concluded.