Effects of aging on dehydroepiandrosterone sulfate in relation to fasting insulin levels and body composition assessed by bioimpedance analysis

Ciliary neurotrophic factor is increased in the plasma of patients with obesity and its levels correlate with diabetes and inflammation indices

To establish whether obesity involves activation of endogenous ciliary neurotrophic factor (CNTF) signalling, we evaluated its plasma levels in patients with obesity and correlated its values with the major clinical and haematological indices of obesity, insulin resistance and systemic inflammation. This study involved 118 subjects: 39 healthy controls (19 men), 39 subjects with obesity (19 men) and 40 subjects with obesity and diabetes (20 men). Plasma CNTF and CNTF receptor α (CNTFRα) were measured using commercial ELISA kits. The results showed that plasma CNTF was significantly higher in males and females with obesity with and without diabetes than in healthy subjects. Women consistently exhibited higher levels of circulating CNTF. In both genders, CNTF levels correlated significantly and positively with obesity (BMI, WHR, leptin), diabetes (fasting insulin, HOMA index and HbA1c) and inflammation (IL-6 and hsCRP) indices. Circulating CNTFRα and the CNTF/CNTFRα molar ratio tended to be higher in the patient groups than in controls. In conclusion, endogenous CNTF signalling is activated in human obesity and may help counteract some adverse effects of obesity. Studies involving a higher number of selected patients may reveal circulating CNTF and/or CNTFRα as potential novel diagnostic and/or prognostic markers of obesity, diabetes and associated diseases.

Effect of APOE polymorphism on obesity and lipid profile in women of differing reproductive status

The aim of this study was to investigate whether the effect of apolipoprotein E polymorphism (APOE) on somatic and lipid risk parameters varies in women of differing reproductive status. We analyzed 447 Slovak women aged between 39 and 90 years. APOE genotypes were determined by PCR-RFLP. Regression analysis confirmed the effect of the APOE genotype on the levels of LDL-cholesterol, apolipoprotein B (apoB), nonHDL-cholesterol and on the three atherogenic indices: apoB-to-apoA1, TC-to-HDLcholesterol, LDL-C-to-HDL-cholesterol. Here, lower mean levels were registered in the E2 carriers than in the E3 and E4 subgroups. However, the impact of menopausal status on lipid parameters was not confirmed. Bonferroni correction showed that systolic blood pressure was significantly lower in the E4 carriers compared to the E3 group (P=0.017). Univariate analysis of covariance revealed a significant interaction between the menopausal group and the APOE group, and their common effect on waist-to-hipratio (WHR). Bonferroni correction in early postmenopausal women showed that the mean WHR values were significantly different between E2 and E4 groups (P=0.008). This study demonstrates that the E*2 allele has a protective effect against higher blood lipid levels. Moreover, the results suggest that E*2 could have a partial negative effect on WHR in early postmenopausal Slovak women.

Correlation of Occupational Stress Index with 24-hour Urine Cortisol and Serum DHEA Sulfate among City Bus Drivers: A Cross-sectional Study

Objectives

The questionnaire of occupational stress index (OSI) has been popular in the workplace, and it has been tailored for bus drivers in Taiwan. Nevertheless, its outcomes for participants are based on self-evaluations, thus validation by their physiological stress biomarker is warranted and this is the main goal of this study.

Methods

A cross-sectional study of sixty-three city bus drivers and fifty-four supporting staffs for comparison was conducted. Questionnaire surveys, 24-hour urine cortisol testing, and blood draws for dehydroepiandrosterone-sulfate (DHEA-S) testing were performed. The measured concentrations of these biological measures were logarithmically transformed before the statistical analysis where various scores of stressor factors, moderators, and stress effects of each OSI domain were analyzed by applying multiple linear regression models.

Results

For drivers, the elevated 24-hour urine cortisol level was associated with a worker's relationship with their supervisor and any life change events in the most recent 3 months. The DHEA-S level was higher in drivers of younger age as well as drivers with more concerns relating to their salary and bonuses. Non-drivers showed no association between any stressor or satisfaction and urine cortisol and blood DHEA-S levels.

Conclusion

Measurements of biomarkers may offer additional stress evaluations with OSI questionnaires for bus drivers. Increased DHEA-S and cortisol levels may result from stressors like income security. Prevention efforts towards occupational stress and life events and health promotional efforts for aged driver were important anti-stress remedies.

Endogenous steroids measured by high-specificity liquid chromatography-tandem mass spectrometry and prevalent cardiovascular disease in 70-year-old men and women

CONTEXT

There is a need for increased knowledge about endogenous sex hormone levels and clinical outcomes of risk/benefit. Immunoassays have poor specificity to reliably measure low steroid concentrations in elderly.

OBJECTIVE

The objective of the study was to evaluate plasma steroid concentrations with regard to prevalent cardiovascular disease (CVD) in elderly, using mass spectrometry.

SETTING

The study was conducted at a university hospital research unit.

DESIGN AND METHODS

Plasma samples were analyzed from 202 70-yr-olds as part of a large population-based study, Prospective Investigation of the Vasculature in Uppsala Seniors. Twenty-eight of these had prevalent CVD. Eleven steroids were quantified, using liquid chromatography-tandem mass spectrometry. Women with current/previous menopausal hormone therapy (n = 35) were excluded.

RESULTS

Men without prevalent CVD had higher plasma 17beta-estradiol (E2), compared with women. Men with prevalent CVD, compared with those without, had lower 17-hydroxypregnenolone (17OHPregn), 17-hydroxyprogesterone, and higher estrone/androstenedione and E2/testosterone (T) (aromatase activity). Women with prevalent CVD had lower pregnenolone, 17OHPregn, and dehydroepiandrosterone (DHEA) but higher DHEA/17OHPregn, androstenedione/DHEA, E2/T, E2/estrone, and E2/SHBG. The aromatase index, E2/T, was higher for prevalent CVD in both sexes. Adjustment for statin use, smoking, and body mass index yielded additional significant differences in men, whereas some were lost in women. Logistic regression indicated strong associations between prevalent CVD and low 17OHPregn, adjusted odds ratio of 0.18, 95% confidence interval (0.06-0.61); P = 0.006, in women and low 17-hydroxyprogesterone, 0.45 (0.25-0.80); P = 0.007 in men, most likely caused by increased throughput (consumption) toward estrogen synthesis.

CONCLUSIONS

Prevalent CVD was associated with indications of lower androgen precursors, increased aromatase activity, and higher estrogen levels in both sexes. Results might represent an endogenous response to a condition of developing atherosclerosis, rather than a causative relationship. Furthermore studies are needed.

ISSN exercise & sport nutrition review: research & recommendations

Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients.

Bioelectrical phase angle values in a clinical sample of ambulatory rehabilitation patients

Background

Phase angle (PhA) is derived from the resistance and reactance measurements obtained from bioelectric impedance analysis (BIA) and is considered indicative of cellular health and membrane integrity. This study measured PhA values of rehabilitation patients and compared them to reference values, measures of functional ability and serum C-reactive protein (CRP) levels to explore their utility as a clinical tool to monitor disease progression and treatment efficacy.

Methods

This cross-sectional observational study was conducted on 215 ambulatory rehabilitation patients aged 20 – 94 years. All participants had been hospitalised for a stroke, orthopaedic or other condition resulting in a functional limitation. PhA was derived from BIA analysis and functional ability characterised using the Functional Independence Measure (FIM), timed up and go (TUG) and maximal quadriceps strength (MQS). Serum levels of CRP were also collected.

Results

Stroke patients had the highest PhA (5.3°) followed by elective orthopaedic surgery (5.0°) with the other group (4.3°) significantly lower than both previous categories (p < 0.001). Ambulatory rehabilitation patients' PhA values were dependent on age and sex (p < 0.001), lower than published age matched healthy reference values (p ≤ 0.05) and similar to other hospitalised or sick groups, but also higher than values reported in critically ill patients. Patients with CRP values less than 10 mg.L^-1 had significantly (p = 0.005) higher mean PhA values. Furthermore, the highest functional status quartiles had significantly higher PhAs (p ≤ 0.04) for the FIM, MQS and TUG measures.

Conclusion

The results suggest that the phase angles of rehabilitation patients are between those of healthy individuals and seriously ill patients, thereby supporting claims that PhA is indicative of general health status. Phase angles are a potentially useful indicator of functional status in patients commencing an ambulatory rehabilitation program with a normal hydration status.

Estimation of individual reference intervals in small sample sizes

In occupational health studies, the study groups most often comprise healthy subjects performing their work. Sampling is often planned in the most practical way, e.g., sampling of blood in the morning at the work site just after the work starts. Optimal use of reference intervals requires that the population, on which the reference interval is based, is representative for the study group in question. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommends estimating reference interval on at least 120 subjects. It may be costly and difficult to gain group sizes of that order of magnitude for all topics in question. Therefore, new methods to estimate reference intervals for small sample sizes are needed. We present an alternative method based on variance component models. The models are based on data from 37 men and 84 women taking into account biological variation from various variables such as gender, age, BMI, alcohol, smoking, and menopause. The reference intervals were compared to reference intervals calculated using IFCC recommendations. Where comparable, the IFCC calculated reference intervals had a wider range compared to the variance component models presented in this study. The presented method enables occupational health researchers to calculate reference intervals for specific groups, i.e. smokers versus non-smokers, etc. In conclusion, the variance component models provide an appropriate tool to estimate reference intervals based on small sample sizes.

Two years of treatment with dehydroepiandrosterone does not improve insulin secretion, insulin action, or postprandial glucose turnover in elderly men or women

To determine if dehydroepiandrosterone (DHEA) replacement improves insulin secretion, insulin action, and/or postprandial glucose metabolism, 112 elderly subjects with relative DHEA deficiency ingested a labeled mixed meal and underwent a frequently sampled intravenous glucose tolerance test before and after 2 years of either DHEA or placebo. Despite restoring DHEA sulphate concentrations to values observed in young men and women, the changes over time in fasting and postprandial glucose concentrations, meal appearance, glucose disposal, and endogenous glucose production were identical to those observed after 2 years of placebo. The change over time in postmeal and intravenous glucose tolerance test insulin and C-peptide concentrations did not differ in men treated with DHEA or placebo. In contrast, postmeal and intravenous glucose tolerance test change over time in insulin and C-peptide concentrations were greater (P < 0.05) in women after DHEA than after placebo. However, since DHEA tended to decrease insulin action, the change over time in disposition indexes did not differ between DHEA- and placebo-treated women, indicating that the slight increase in insulin secretion was a compensatory response to a slight decrease in insulin action. We conclude that 2 years of replacement of DHEA in elderly men and women does not improve insulin secretion, insulin action, or the pattern of postprandial glucose metabolism.

Hyperglycaemia acutely decreases circulating dehydroepiandrosterone levels in healthy men

OBJECTIVE

This study was conducted in order to evaluate the effect of glucose-insulin homeostasis on adrenal steroids and was designed to separate the effects of hyperglycaemia from those of insulin.

DESIGN

Eight healthy men aged 22.6 +/- 3.4 (SD) underwent an 80 mU/m2/min hyperinsulinaemic euglycaemic 100-min clamp, a 200-min graded glucose infusion at 2-16 mg/kg/min and a measurement of fat mass.

MEASUREMENTS

Circulating glucose, insulin and adrenal steroid levels including dehydroepiandrosterone (DHEA) were determined before and during both infusion tests. Steroid variations in relation to insulinaemia and glycaemia were analysed using univariate, multivariate tests and nonlinear mixed models.

RESULTS

Hyperinsulinaemia induced no significant modification of adrenal steroid levels. By contrast, hyperglycaemia decreased all adrenal steroids except DHEA-sulphate by 47-66%. The drop occurred early, averaging 51% for 17OH pregnenolone and 57% for DHEA at the 80th minute of glucose infusion, whereas blood glucose was 7.1 +/- 1.2 mmol/1. This effect was independent of insulinaemia, fat mass and waist circumference. Thus, we estimated models that could best predict steroid variations according to blood glucose. At thresholds defining impaired fasting glycaemia and diabetes, the estimated decrease in DHEA was 40% and 45%, respectively, culminating at 60% at 9.3 mmol/1 glycaemia, with no detectable further decrease.

CONCLUSIONS

Our data suggest that hyperglycaemia dramatically decreases adrenal androgen levels in men, possibly by acting at early steps of synthesis, independently of insulinaemia and fat mass.

Effect of DHEAS on skeletal muscle over the life span: the InCHIANTI study

BACKGROUND

It has been suggested that the reduced production of dehydroepiandrosterone sulfate (DHEAS) may be partially responsible for the decline of muscle strength and mass that often occurs with aging. However, this hypothesis has been only tested in small series of normal volunteers, with little consideration for potential confounders. Using data from a representative sample of 558 men (20-95 years) we tested the hypothesis that circulating DHEAS is independently associated with muscle strength and mass.

METHODS

Data are from InCHIANTI, an epidemiological study conducted in the Chianti geographic area (Tuscany, Italy). DHEAS serum levels were related to lower extremity muscle strength assessed by hand-held dynamometry and calf muscle area estimated from quantitative computerized tomography. Confounders included age, anthropometrics, physical activity, smoking, energy and alcohol intake, albumin, lipids, interleukin-6, comorbidity, depressive symptoms, and disability in activities of daily living.

RESULTS

In fully adjusted models predicting lower extremity muscle strength and calf muscle area, we found significant age*log DHEAS interactions, suggesting that the relationship between DHEAS levels and muscle parameters differs across the life span. In age-stratified models adjusted for confounders, serum DHEAS was an independent predictor of muscle strength (p <.02) and mass (p <.01), but only for men between 60 and 79 years of age. After adjusting these models for serum-free or bioavailable testosterone, results were unchanged.

CONCLUSIONS

In men aged 60-79 years, circulating DHEAS is an independent correlate of muscle strength and calf muscle area. The possible causal role of declining DHEAS in age-related sarcopenia should be further explored in longitudinal studies.

ISSN Exercise & Sport Nutrition Review: Research & Recommendations

Sport nutrition is a constantly evolving field with literally thousands of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper presents a well-referenced overview of the current state of the science related to how to optimize training through nutrition. More specifically, this article discusses: 1.) how to evaluate the scientific merit of nutritional supplements; 2.) general nutritional strategies to optimize performance and enhance recovery; and, 3.) our current understanding of the available science behind weight gain, weight loss, and performance enhancement supplements. Our hope is that ISSN members find this review useful in their daily practice and consultation with their clients.

Steroid sulfatase gene variation and DHEA responsiveness to resistance exercise in MERET

Genetic influences and endurance exercise have been shown to alter circulating concentrations of dehydroepiandrosterone (DHEA) and its sulfated conjugate, DHEAS. We hypothesized that acute resistance exercise (RE) and training (RET) would increase DHEA steroids, and the magnitude of the increase would be influenced by a steroid sulfatase (STS) gene variation. Fasting blood samples were collected before and after the first ( S1) and last ( S30) session of a 10-wk RET program in 62 men and 58 women [age: 21.0 yr (2.4)]. Acute RE increased both DHEA [+2.8 (0.4), S1; +1.6 ng/ml (0.4), S30; P < 0.001] and DHEAS [+154 ( 24 ), S1; +166 ng/ml ( 15 ), S30; P < 0.001] and decreased DHEAS:DHEA [−27 ( 8 ), S1; −15 ( 7 ), S30; P < 0.01]. RET reduced resting DHEAS (−122 ng/ml, P < 0.01) and decreased DHEA response to RE (−50%, P < 0.05). Subjects with an STS “G” allele ( n = 36) had greater acute changes in DHEA [+4.4 (0.7) vs. +2.0 ng/ml (0.5), S1; +3.2 (0.6) vs. +1.0 ng/ml (0.4), S30; P < 0.01] and DHEAS:DHEA [−37 ( 11 ) vs. 5 ( 7 ), S30, P < 0.05] than those subjects with only an “A” allele ( n = 84). The observed increase in DHEA and DHEAS and decrease in DHEAS:DHEA suggest RE-induced STS activation which is influenced by the STS polymorphism.

Reliability and variability of bioimpedance measures in normal adults: Effects of age, gender, and body mass

This study aimed to analyze the reliability and evaluate the causes of variability of bioimpedance parameters. Direct measures were analyzed because they are not affected by inappropriate prediction models. Resistance (R), reactance (Xc), and phase angle (PA) were determined at three fixed frequencies (5, 50, and 100 kHz) in 653 normal Germans (244 males and 409 females), aged 20-90 years, using a phase-sensitive whole-body tetrapolar bioimpedance analyzer (BIA 2000-M, Data Input, Germany). From these values, six bioimpedance ratios were calculated (R(5)/R(50), R(5)/R(100), Xc(5)/Xc(50), Xc(5)/Xc(100), PA(5)/PA(50), and PA(5)/PA(100)). Reliability of duplicate measurements, as determined by technical error, is high. ANOVA for repeated measurements yields a significant frequency main effect (within-subjects factor) and significant effects of age and gender (between-subject factors) on variation of resistance, reactance, and phase angle. Multiple regression analyses indicate independent effects of age, gender, and body mass index on variability of resistance, reactance, and phase angle at the three frequencies. Gender primarily influences variation in resistance (smaller values in males), whereas age mainly affects variations in reactance and phase angle (smaller values in older adults). Obesity is associated with smaller resistance (at all frequencies) and smaller reactance (high frequencies), but larger phase-angle values (low frequency). The study shows that variability of direct bioimpedance measures depends on age, gender, and body mass characteristics of the study population. The potential benefit for using both low and high frequencies in R measures is to differentiate between extra- and intracellular fluid spaces, which may be altered during human growth and aging.

Body mass index, waist/hip ratio and androgen-estrogen activity in younger versus older Polish men

This study was performed to evaluate the associations between estradiol, dehydroepiandrosterone sulfate (DHEAS), free and total testosterone levels, and anthropometric parameters of general adiposity (body mass index, BMI) and fat distribution (waist/hip ratio, WHR), separately in two subgroups of healthy Polish men: younger (aged 22-39 years, n = 95) and older (aged 40 years and over, n = 141) subjects. Sex steroid levels were assessed using radioimmunoassay (RIA). BMI was used as a measure of general adiposity. WHR was used to estimate distribution of adipose depots. The relationships between sex steroids, BMI, WHR and age were evaluated by use of non-parametric statistics (Spearman coefficients). Aging was related to a reduction of all hormone levels (correlation coefficients with age: free testosterone r = -0.52, p < 0.001; total testosterone r = -0.25, p < 0.001; estradiol r = -0.18, p < 0.001; DHEAS r = -0.45, p < 0.001) and an increase of BMI and WHR for BMI r = 0.23, p < 0.001; for WHR r = 0.47, p < 0.001). A one way analysis of co-variance (ANCOVA) was applied separately in the two subgroups of subjects to assess the relationships between hormonal and anthropometric variables. In men aged 22-39 years, the total (but not free) testosterone and DHEAS (when controlled for age) significantly differentiated BMI values. In subjects aged 40 years and over, no associations between sex steroids and BMI were revealed. In younger males DHEAS differentiated WHR values (even when controlled for age and BMI), whereas after the age of 40 years an increased WHR was accompanied by increases in both estradiol and DHEAS levels. The associations between the androgen-estrogen activity and the anthropometric parameters of adiposity vary in younger versus older healthy men.

Relations of insulin resistance and serum concentrations of estradiol and sex hormone-binding globulin to potential breast cancer risk factors

There is a hypothesis that hyperinsulinemia or insulin resistance may be a mediator for breast cancer risk factors. On the other hand, some, but not all, of the well-known risk factors of breast cancer have been associated with serum estrogen concentrations. We assessed the relationships of potential breast cancer risk factors to indicators of insulin resistance, fasting plasma insulin concentration and homeostasis model assessment insulin resistance (HOMA-R), in 88 postmenopausal Japanese women. We also examined whether insulin resistance would explain the association of breast cancer risk factors with serum estradiol and sex hormone-binding globulin (SHBG). Information on potential breast cancer risk factors, such as demographic characteristics, smoking and drinking habits, diet, exercise, menstrual and reproductive factors, was obtained by self-administered health questionnaire including a validated semiquantitative food frequency questionnaire. Body mass index (BMI) was significantly correlated with the ratio of estradiol to SHBG (Spearman r = 0.30, P = 0.0004), fasting plasma insulin (r = 0.45) and HOMA-R (r = 0.43, P = 0.0001) after controlling for age. The correlations were still significant between BMI and estradiol / SHBG ratio (r = 0.21, P = 0.047) after controlling for fasting plasma insulin and between BMI and fasting plasma insulin (r = 0.40, P = 0. 0001) as well as HOMA-R (r = 0.38, P = 0.0003) after controlling for estradiol / SHBG ratio. There is a possibility that effect of BMI on breast cancer risk is mediated by both insulin resistance and estrogen metabolism.

No association between dehydroepiandrosterone sulfate and development of atherosclerosis in a prospective population study (Bruneck Study)

Antiatherogenic properties of dehydroepiandrosterone (DHEA) have been postulated for >40 years. Large-scale epidemiological studies on this important issue, however, are still sparse, and those available have yielded contradictory results. The Bruneck Study involved a large random sample of men and women aged 40 to 79 years that were enrolled in 1990 and reevaluated 5 years later. Baseline DHEA sulfate (DHEAS) levels were measured in 867 subjects after an overnight fast. Development and progression of carotid atherosclerosis was monitored by high-resolution duplex ultrasound. DHEAS levels declined with advancing age (29% and 44% per decade in men and women) and showed a complex sex-specific association with various vascular risk attributes and factors conferring protection against atherosclerosis. Age- and sex-adjusted DHEAS baseline levels did not differ between subjects with or without incident/progressive atherosclerosis (geometric mean 1161 versus 1253 microg/L). After adjustment for vascular risk factors and potential confounders, the odds ratio of incident/progressive atherosclerosis comparing a 50% increase in DHEAS levels was 0.99 (95% CI 0.89 to 1.11). Lack of an association between DHEAS and atherogenesis was confirmed in sex-specific and a variety of supplementary analyses. Statistical power would be high enough to detect differences in DHEAS between outcome categories as low as 15% (alpha=0.05). This prospective community-based study does not support a role for endogenous DHEA(S) in the development of human atherosclerosis.

Effects of dehydroepiandrosterone vs androstenedione supplementation in men

PURPOSE

The purpose of this study was to compare the effects of short-term (12 wk) supplementation with androstenedione versus dehydroepiandrosterone (DHEA) on body composition, strength, and related hormones in middle-aged men.

METHODS

A randomized, placebo-controlled, double-blind design was used to study 40 healthy, trained (>1 yr weight training) male subjects (mean +/- SD: age 48.1 +/- 3.9 yr; weight 79.8 +/- 9.8 kg). Subjects were randomly assigned to one of three groups: placebo (P), DHEA (D), or androstenedione (A). Supplements (50 mg capsules) were ingested two times daily for 12 wk. All testing, including venous blood samples, body composition, and performance, was conducted at three time points: presupplementation (1 d), at 6 wk, and postsupplementation (12 wk).

RESULTS

Despite a small increase in lean body mass (0.8 +/- 0.4 and 0.5 +/- 0.3 kg) and mean strength (6.8 +/- 2.7 and 5.7 +/- 2.4 kg) in both D and A groups respectively, these changes were not significantly different from P. In D, there was a significantly greater increase in DHEA-S levels than in P (P < 0.05). There were no adverse side effects demonstrated during D or A supplementation including significant changes in PSA, liver function, or lipid levels (P < 0.05).

CONCLUSIONS

The results of this study suggest that supplementation with 100 mg x d(-1) of either androstenedione or DHEA does not independently elicit a statistically significant increase in lean body mass, strength, or testosterone levels in healthy adult men over a 12-wk period.

Plasma adrenal, gonadal, and conjugated steroids before and after long-term overfeeding in identical twins

An analysis of the data collected in the Quebec Overfeeding Study of identical twins was undertaken to determine any evidence of a genotype effect on plasma levels of adrenal and gonadal steroids arising from long term positive energy balance. Plasma levels of sex hormone-binding globulin (SHBG), testosterone, dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA-S), androsterone glucuronide, androstane-3 alpha, 17 beta-diol glucuronide (3 alpha-DIOL-G), and cortisol were measured in 12 pairs of young, sedentary, male monozygotic twins before and after 100 days of overfeeding. The dietary energy excess of 4.2 MJ/day (1000 Cal), 6 days a week, resulted in a total positive energy balance of 353 MJ (84,000 Cal). Overfeeding induced significant changes (P < 0.0001) in body weight and other measures of body composition. Within-twin pair resemblance was observed at baseline in all steroids, except cortisol [intraclass correlation range: DHEA-S, 0.50 (P < 0.05); DHT, 0.77 (P < 0.001)] and was lost with overfeeding, except for DHT and SHBG (P < 0.05). SHBG levels fell and 3 alpha-DIOL-G rose with the gain in body fatness. The change in testosterone was a significant correlate of the change in upper body fat (r = -0.48; P < 0.05). The change in 3 alpha-DIOL-G correlated positively with increases in all measures of central adiposity (r = 0.52; P < 0.01). A decrease in DHEA-S occurred with a higher, but not with a lower, gain in abdominal visceral fat (P < 0.05). Thus, analysis of adrenal and gonadal steroids and of conjugated metabolites before and after overfeeding in monozygous twins supports the idea that there is a genotype effect on steroid circulating steroid levels and that these blood levels are correlated with the pattern of body fat distribution. Moreover, the baseline within-twin pairs similarity in steroid levels was attenuated by prolonged positive energy balance and body fat gain.