Population-based studies suggest that repetitive cycling of
weight loss and regain may be associated with future
weight gain. Therefore, to better define the relationship between
weight cycling, energy homeostasis, and future
weight gain, we examined associations between frequent intentional
weight loss and hormonal profiles in postmenopausal women. This cross-sectional study evaluated the relationship between a history of frequent
weight loss and
biomarkers, including serum
glucose,
insulin,
leptin, and
ghrelin, as well as
sex steroid hormones. We hypothesized that frequent intentional
weight loss would be associated with changes in normal appetite and
body weight regulatory
hormones, favoring increased appetite and
weight gain. One hundred fifty-nine healthy, weight stable, sedentary,
overweight, postmenopausal women who had been recruited for an exercise intervention participated in this study. History of intentional
weight loss (frequency and magnitude) was assessed by questionnaire. Hormonal assays were performed by radioimmunoassay (
insulin,
leptin,
ghrelin,
estrogens,
androgens, and
dehydroepiandrosterone), chemiluminescence immunoassay (insulin-like growth factor-1), and immunometric assay (
sex hormone binding globulin). Analysis of variance and regression analyses were used to investigate the relationship between
weight loss history and metabolic
hormones. A higher degree of
weight cycling, characterized by the frequency of intentionally losing more than 10 lb, was associated with an appetite-stimulating hormonal profile, including higher concentrations of
ghrelin (P trend = .04), lower
glucose (P trend = .047), and to some extent, lower
insulin (P trend = .08). Frequent
weight loss was also associated with lower
androgen concentrations, including
androstenedione (P trend = .02),
testosterone (P trend = .04), and free
testosterone (P trend = .01). No independent associations between the concentrations of
leptin or
estrogens and
weight cycling were observed. This study suggests that frequent intentional
weight loss may affect
hormones involved in energy regulation.