Sex hormones and sexual function in obese men losing weight

Total testosterone levels are correlated to metabolic syndrome components

INTRODUCTION

Metabolic syndrome (MetS) is a constellation of interrelated risk factors of metabolic origin. Some studies suggest a possible link between low total testosterone (TT) levels and the presence of MetS.

AIM

To analyze the strength and independence of associations between TT and MetS components in non-diabetic men.

METHODS

In this cross-sectional study, 143 non-diabetic men older than 40 were analyzed.

MAIN OUTCOMES MEASURE

Blood samples were collected to evaluate metabolic profile and TT levels. MetS was defined as the presence of three or more of the following characteristics: fasting blood glucose levels ≥ 100 mg/dL, triglyceride ≥ 150 mg/dL, HDL-c < 40 mg/dL, hypertension or blood pressure ≥ 130/85 mmHg, and waist girth > 102 cm.

RESULTS

Mean age of the study population was 61.5 ± 8.61 years old. MetS was present in 47.9% of the individuals. Thirty-four men had low TT and MetS was observed in 23 (70%) against 50 (46%) in those with normal TT (≥ 300 ng/dL) (OR 4.94, p < 0.01), adjusted to confounder's factors. In multiple linear regression analysis, only waist circumference (Beta: -0.395; p = 0.03) and HDL-c (Beta: 0.19; p = 0.04) remained significantly correlated with TT levels.

CONCLUSIONS

Low TT levels were associated with MetS diagnosis. Abdominal obesity was the MetS component independently correlated to low TT levels.

Current medical management of endocrine-related male infertility

Male factor contributes to 50%-60% of overall infertility but is solely responsible in only 20% of couples. Although most male factor infertility is ascertained from an abnormal semen analysis, other male factors can be contributory especially if the sample returns normal. Male infertility can be due to identifiable hormonal or anatomical etiologies that may be reversible or irreversible. This manuscript will highlight existing guidelines and our recommendations for hormone evaluation for male infertility and empiric therapies including multivitamins, estrogen receptor modulators (clomiphene), estrogen conversion blockers (anastrozole), and hormone replacement.

Effect of Lifestyle Intervention on the Hormonal Profile of Frail, Obese Older Men

OBJECTIVE

Obesity-associated hypogonadism is hypothesized to be due to the suppressive effect of high estradiol (from an increase in aromatase activity present in the abundant adipose tissue) on the hypothalamic-pituitary-gonadal unit resulting in low testosterone production. Although weight loss has been found to be effective in reducing estradiol and raising testosterone levels in studies of younger men, its effect in frail, obese older men is understudied. Thus, the objective of this study was to determine the effect of lifestyle intervention on hormone levels in frail, obese older men.

DESIGN

Randomized controlled trial of lifestyle intervention in frail, obese older men (≥65 yo) for 1 year.

SETTING

University hospital.

METHODS

Forty frail, obese elderly men were randomized, for a 52-week study, to any of the following treatment groups: (1) control group, (2) diet-induced weight loss group (diet group), (3) exercise training group (exercise group), and (4) diet-induced weight loss and exercise training group (diet-exercise group). The objective was to achieve a ~10 % weight loss at 6 months and maintain this weight for an additional 6 months. Physical function was assessed by the modified physical performance testing (modified PPT). Estradiol was measured by radioimmunoassay, testosterone by automated immunoassay, and sex hormone-binding globulin by enzyme-linked immunoassay.

RESULTS

After 12 months of intervention, diet alone resulted in a weight loss of -10.1 ± 1.9 kg in the diet group and -9.1 ± 0.9 kg in the diet-exercise group. This resulted in a significant decrease (both p<0.05) in total estradiol compared to baseline among subjects in the diet (-2.5 ± 1.3 pg/ml) and diet-exercise group (-2.2 ± 4.0 pg/ml). Free estradiol index also significantly decreased (both p <0.05) in both the diet (-0.39 ± 0.14 pmol/nmol) and diet-exercise (-0.52 ± 0.12 pmol/nmol) group. Total testosterone significantly increased (p<0.05) in response to diet (71.0 ± 21.0 ng/dl) and diet-exercise (49.9 ± 15.5 pg/ml) resulting in values of 287.0 ± 28.1 ng/dl in the diet and 317.6 ± 33.1 ng/dl in the diet-exercise group. However, because there was a significant increase in sex hormone-binding globulin levels in both the diet and diet-exercise groups, free testosterone index and the changes in free testosterone index were not significant compared to baseline. Regardless of changes in hormonal levels, patients in the diet, exercise, and diet-exercise groups experienced significant improvements in the modified PPT from baseline.

CONCLUSION

Weight loss from lifestyle intervention resulted in significant decreases in total and free estradiol levels in frail, obese older men, but this did not result in a clinically important increase in total testosterone nor a significant increase in free testosterone. Thus, alternative forms of treatment in addition to lifestyle intervention may be necessary to improve the hormonal profile among these patients. Nevertheless, whether further improvement in hormonal profile would result in better physical performance than what can be achieved by lifestyle alone in these subjects remains uncertain.

Androgen deficiency and metabolic syndrome in men

Metabolic syndrome (MetS) is a growing health concern worldwide. Initially a point of interest in cardiovascular events, the cluster of HTN, obesity, dyslipidemia, and insulin resistance known as MetS has become associated with a variety of other disease processes, including androgen deficiency and late-onset hypogonadism (LOH). Men with MetS are at a higher risk of developing androgen deficiency, and routine screening of testosterone (T) is advised in this population. The pathophysiology of androgen deficiency in MetS is multifactorial, and consists of inflammatory, enzymatic, and endocrine derangements. Many options for the concomitant treatment of both disorders exist. Direct treatment of MetS, whether by diet, exercise, or surgery, may improve T levels. Conversely, testosterone replacement therapy (TRT) has been shown to improve MetS parameters in multiple randomized controlled trials (RTCs).

Changes in Testosterone Levels and Sex Hormone-Binding Globulin Levels in Extremely Obese Men after Bariatric Surgery

Objective. Obesity is a risk factor for hypogonadotropic hypogonadism in men. Weight loss has been shown to improve hypogonadism in obese men. This study evaluated the early changes in sex hormones profile after bariatric surgery. Methods. This is a prospective study including 29 morbidly obese men. Main outcomes were changes in serum levels of total testosterone (TT), free testosterone (cFT), SHBG, estradiol, adiponectin, and leptin at 1 and 6 months after surgery. Results. The mean age of patients was 31 ± 8 years and the mean BMI was 56.8 ± 11.7 kg/m². Fifteen patients underwent Roux-en-Y gastric bypass and 14 patients underwent sleeve gastrectomy. At baseline, 22 patients (75.9%) had either low TT levels (<10.4 nmol/L) or low cFT levels (<225 pmol/L). Total testosterone and SHBG levels increased significantly at 1 month after surgery (p ≤ 0.001). At 6 months after surgery, TT and cFT increased significantly (p ≤ 0.001) and 22 patients (75.9%) had normalized TT and cFT levels. There were no changes in estradiol levels at either 1 month or 6 months after surgery. Conclusions. Increases in TT and SHBG levels occurred early at 1 month after bariatric surgery while improvements in cFT levels were observed at 6 months after bariatric surgery.

[Gender Obesity Report--Influence of obesity on Reproduction and Pregnancy]

Obesity influences reproduction in men and women at all ages. The increasing prevalence of obesity is associated with rising numbers of reproductive disorders in both sexes. Obesity influences menstrual cycle and ovulation irregularities, increases pregnancy complications and complication rates in assisted reproductive technologies in women and in men obesity is associated with lower semen parameters. Weight loss through lifestyle changes or bariatric surgery has positive effects on hormonal parameters and fertility in both men and women.

Increased physical activity has a greater effect than reduced energy intake on lifestyle modification-induced increases in testosterone

Obesity has reached epidemic proportions worldwide. Obesity results in reduced serum testosterone levels, which causes many disorders in men. Lifestyle modifications (increased physical activity and calorie restriction) can increase serum testosterone levels. However, it is unknown whether increased physical activity or calorie restriction during lifestyle modifications has a greater effects on serum testosterone levels. Forty-one overweight and obese men completed a 12-week lifestyle modification program (aerobic exercise training and calorie restriction). We measured serum testosterone levels, the number of steps, and the total energy intake. We divided participants into two groups based on the median change in the number of steps (high or low physical activities) or that in calorie restriction (high or low calorie restrictions). After the program, serum testosterone levels were significantly increased. Serum testosterone levels in the high physical activity group were significantly higher than those in the low activity group. This effect was not observed between the groups based on calorie restriction levels. We found a significant positive correlation between the changes in serum testosterone levels and the number of steps. Our results suggested that an increase in physical activity greatly affected the increased serum testosterone levels in overweight and obese men during lifestyle modification.

Improvement in erectile function following weight loss in obese men: the SHED-IT randomized controlled trial

In a randomized controlled trial 145 sexually active overweight/obese men received either a male only SHED-IT (Self Help Exercise and Diet Using IT) weight loss program or a wait-list control. Erectile function (IIEF-5) was compared between men in the active intervention versus controls. IIEF-5 was assessed at baseline, 3 months (post-intervention) and 6 months (3-month follow-up). Intention-to-treat analysis revealed a significant intervention effect for erectile function (p = 0.018) at 6 months (+1.4; 95% CI 0.3,2.4; d = 0.32). A minimal contact, gender-tailored weight loss program significantly improved men's erectile function. Further studies evaluating change in erectile function with weight loss are warranted.

Testosterone and obesity

Testosterone is a key hormone in the pathology of metabolic diseases such as obesity. Low testosterone levels are associated with increased fat mass (particularly central adiposity) and reduced lean mass in males. These morphological features are linked to metabolic dysfunction, and testosterone deficiency is associated with energy imbalance, impaired glucose control, reduced insulin sensitivity and dyslipidaemia. A bidirectional relationship between testosterone and obesity underpins this association indicated by the hypogonadal-obesity cycle and evidence weight loss can lead to increased testosterone levels. Androgenic effects on enzymatic pathways of fatty acid metabolism, glucose control and energy utilization are apparent and often tissue specific with differential effects noted in different regional fat depots, muscle and liver to potentially explain the mechanisms of testosterone action. Testosterone replacement therapy demonstrates beneficial effects on measures of obesity that are partially explained by both direct metabolic actions on adipose and muscle and also potentially by increasing motivation, vigour and energy allowing obese individuals to engage in more active lifestyles. The degree of these beneficial effects may be dependent on the treatment modality with longer term administration often achieving greater improvements. Testosterone replacement may therefore potentially be an effective adjunctive treatment for weight management in obese men with concomitant hypogonadism.

How does obesity affect fertility in men - and what are the treatment options?

Adiposity is associated with reduced fertility in men. The aetiology is multifactorial, with obese men at greater risk of suffering from impaired spermatogenesis, reduced circulating testosterone levels, erectile dysfunction and poor libido. The diagnosis and treatment of reduced fertility observed in obese men therefore requires insight into the underlying pathology, which has hormonal, mechanical and psychosocial aspects. This article summarises the current epidemiological, experimental and clinical trial evidence from the perspective of a practicing clinician. The following conclusions and recommendations can be drawn: Obesity is associated with low serum testosterone concentrations, but treatment with exogenous testosterone is likely to adversely impact on fertility. It is important to discuss this with men prior to initiation of testosterone therapy. Obesity adversely affects sperm concentration and may affect sperm quality. However, whether or not weight loss will correct these factors remain to be established. Oestrogen receptor modulators (and aromatase inhibitors) are unlicensed in the treatment for male hypogonadism and/or infertility. These treatments should hence be considered experimental approach until ongoing clinical trials report their outcomes.

Total testosterone is the most valuable indicator of metabolic syndrome among various testosterone values in middle-aged Japanese men

Endogenous testosterone is known to be protective against metabolic syndrome (MetS) in men. While various markers of testosterone status including serum total testosterone (TT), free testosterone (measured using analogue ligand RIA [aFT]), calculated FT (cFT), calculated bioavailable testosterone (cbT), and sex-hormone binding globulin (SHBG) are recognized, it is unclear which of these markers are the most appropriate ones for the detection of MetS. We measured various testosterone values and metabolic markers in 249 healthy Japanese males (mean age 52.7 ± 7.4 yr) and analyzed which testosterone value is most associated with various metabolic parameters, including MetS as diagnosed according to the International Diabetes Federation (IDF, 2009 version) or with the Japanese criteria. Age had no effect on the TT level but significantly decreased aFT, cFT, and cbT levels and significantly increased the SHBG level. All testosterone values and SHBG showed weak inverse relationships with the metabolic markers BMI, waist circumference, insulin, HOMA-R, and HOMA-β, with the strongest relationship being to TT. TT and SHBG were significantly lower in men with MetS than in men without MetS. All testosterone values gradually decreased as the number of MetS components increased. Multivariate analysis revealed that the TT median value of <4.0 ng/mL was the only significant marker for the detection of MetS. These results were essentially the same regardless of whether the diagnosis of MetS was based on the IDF or the Japanese criteria. In conclusion, among various testosterone values, TT is the most reliable indicator of MetS in middle-aged Japanese men.

Sexual functioning and sex hormones in men who underwent bariatric surgery

BACKGROUND

The relationship between obesity and impairments in male sexual functioning is well documented. Relatively few studies have investigated changes in sexual functioning and sex hormones in men who achieve significant weight loss with bariatric surgery. The objective of this study was to assess changes in sexual functioning, sex hormones, and relevant psychosocial constructs in men who underwent bariatric surgery.

METHODS

A prospective cohort study of 32 men from the Longitudinal Assessment of Bariatric Surgery-2 (LABS) investigation who underwent a Roux-en-Y gastric bypass (median body mass index [25th percentile, 75th percentile] 45.1 [42.0, 52.2]) and completed assessments between 2006 and 2012. Bariatric surgery was performed by a LABS-certified surgeon. Sexual functioning was assessed by the International Index of Erectile Functioning (IIEF). Hormones were assessed by blood assay. Quality of life (QoL), body image, depressive symptoms and marital adjustment were assessed by questionnaire.

RESULTS

Men lost, on average, (95% confidence interval) 33.3% (36.1%, 30.5%) of initial weight at postoperative year 1, 33.6% (36.8%, 30.5%) at year 2, 31.0% (34.1%, 27.9%) at year 3, and 29.4% (32.7%, 26.2%) at year 4. Participants experienced significant increases in total testosterone (P<.001) and sex hormone binding globulin (SHBG) (P<.001) through postoperative year 4. Although men reported improvements in sexual functioning after surgery, these changes did not significantly differ from baseline, with the exception of overall satisfaction at postoperative year 3 (P = .008). Participants reported significant improvements in physical domains of health-related quality of life (HRQoL), all domains of weight-related QOL, and body image, but not in the mental health domains of HRQoL or relationship satisfaction.

CONCLUSIONS

Men who lost approximately one third of their weight after Roux-en-Y gastric bypass experienced significant increases in total testosterone and SHBG. They did not, however, report significant improvements in sexual functioning, relationship satisfaction, or mental health domains of HRQoL. This pattern of results differs from that of women who have undergone bariatric surgery, who reported almost uniform improvements in sexual functioning and psychosocial status.

Lowered testosterone in male obesity: mechanisms, morbidity and management

With increasing modernization and urbanization of Asia, much of the future focus of the obesity epidemic will be in the Asian region. Low testosterone levels are frequently encountered in obese men who do not otherwise have a recognizable hypothalamic-pituitary-testicular (HPT) axis pathology. Moderate obesity predominantly decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity is additionally associated with reductions in free testosterone levels due to suppression of the HPT axis. Low testosterone by itself leads to increasing adiposity, creating a self-perpetuating cycle of metabolic complications. Obesity-associated hypotestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity by itself, in the absence of symptomatic androgen deficiency, is not an established indication for testosterone therapy. Testosterone therapy may lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy augments diet- and exercise-induced weight loss requires evaluation in adequately designed randomized controlled clinical trials.

Testosterone level in men with type 2 diabetes mellitus and related metabolic effects: A review of current evidence

A significant proportion of patients with type 2 diabetes mellitus have a low testosterone level relative to reference ranges based on healthy young men. Only a small number of these patients suffer from classical hypogonadism as a result of recognizable hypothalamic-pituitary-gonadal axis pathology. The cut-off value of the serum testosterone level in men without obvious hypothalamic-pituitary-gonadal axis pathology is controversial. It is unclear to what extent a low serum testosterone level causally leads to type 2 diabetes and/or the metabolic syndrome. From a theoretical standpoint, there can be complex interactions among the hypothalamic-pituitary-gonadal axis, body composition and insulin resistance, which can be further influenced by intrinsic and extrinsic factors to give rise to metabolic syndrome, glucose intolerance, and low-grade inflammation to increase the risk of cardiovascular disease. Although a low serum testosterone level frequently coexists with cardiometabolic risk factors and might serve as a biomarker, more studies are required to clarify the causal, mediating or modifying roles of low serum testosterone level in the development of adverse clinical outcomes. Currently, there are insufficient randomized clinical trial data to evaluate the effects of testosterone replacement therapy on meaningful clinical outcomes. The risk-to-benefit ratio of testosterone therapy in high-risk subjects, such as those with type 2 diabetes, also requires elucidation. The present article aims to review the current evidence on low serum testosterone levels in patients with type 2 diabetes, and its implications on cardiovascular risk factors, metabolic syndrome and adverse clinical outcomes.

Testosterone, sex hormone-binding globulin and the metabolic syndrome in men: an individual participant data meta-analysis of observational studies

Background

Low total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations have been associated with the metabolic syndrome (MetS) in men, but the reported strength of association varies considerably.

Objectives

We aimed to investigate whether associations differ across specific subgroups (according to age and body mass index (BMI)) and individual MetS components.

Data sources

Two previously published meta-analyses including an updated systematic search in PubMed and EMBASE.

Study Eligibility Criteria

Cross-sectional or prospective observational studies with data on TT and/or SHBG concentrations in combination with MetS in men.

Methods

We conducted an individual participant data meta-analysis of 20 observational studies. Mixed effects models were used to assess cross-sectional and prospective associations of TT, SHBG and free testosterone (FT) with MetS and its individual components. Multivariable adjusted odds ratios (ORs) and hazard ratios (HRs) were calculated and effect modification by age and BMI was studied.

Results

Men with low concentrations of TT, SHBG or FT were more likely to have prevalent MetS (ORs per quartile decrease were 1.69 (95% CI 1.60-1.77), 1.73 (95% CI 1.62-1.85) and 1.46 (95% CI 1.36-1.57) for TT, SHBG and FT, respectively) and incident MetS (HRs per quartile decrease were 1.25 (95% CI 1.16-1.36), 1.44 (95% 1.30-1.60) and 1.14 (95% 1.01-1.28) for TT, SHBG and FT, respectively). Overall, the magnitude of associations was largest in non-overweight men and varied across individual components: stronger associations were observed with hypertriglyceridemia, abdominal obesity and hyperglycaemia and associations were weakest for hypertension.

Conclusions

Associations of testosterone and SHBG with MetS vary according to BMI and individual MetS components. These findings provide further insights into the pathophysiological mechanisms linking low testosterone and SHBG concentrations to cardiometabolic risk.

In subfertile couple, abdominal fat loss in men is associated with improvement of sperm quality and pregnancy: a case-series

Background

The impact of overweight among men of reproductive-age may affect fertility. Abdominal fat, more than body mass index, is an indicator of higher metabolic risk, which seems to be involved in decreasing sperm quality.

This study aims to assess the relationship between abdominal fat and sperm DNA fragmentation and the effect of abdominal fat loss, among 6 men in subfertile couples.

Methods

Sperm DNA fragmentation, abdominal fat and metabolic and hormonal profiles were measured in the 6 men before and after dietary advices. Seminal oxidative stress and antioxidant markers were determined.

Results

After several months of a lifestyle program, all 6 men lost abdominal fat (patient 1: loss of 3 points of abdominal fat, patient 2: loss of 3 points, patient 3: loss of 2 points, patient 4: loss of 1 point, patient 5: loss of 4 points and patient 6: loss of 13 points). At the same time, their rate of sperm DNA fragmentation decreased: 9.5% vs 31%, 24% vs 43%, 18% vs 47%, 26.3% vs 66%, 25.4% vs 35% and 1.7% vs 25%. Also, an improvement in both metabolic (significant decrease in triglycerides and total cholesterol; p = 0.0139) and hormonal (significant increase in testosterone/oestradiol ratio; p = 0.0139) blood profiles was observed after following the lifestyle program. In seminal plasma, the amount of SOD2 has significantly increased (p = 0.0139) while in parallel carbonylated proteins have decreased. Furthermore, all spouses got pregnant. All pregnancies were brought to term.

Conclusion

This study shows specifically that sperm DNA fragmentation among men in subfertile couples could be affected by abdominal fat, but improvement of lifestyle factor may correct this alteration. The effect of specific abdominal fat loss on sperm quality needs further investigation. The reduction of oxidative stress may be a contributing factor.

Adiposopathy: how do diet, exercise and weight loss drug therapies improve metabolic disease in overweight patients?

An increase in bodyweight is generally associated with an increased risk of excessive fat-related metabolic diseases (EFRMD), including Type 2 diabetes mellitus, hypertension and dyslipidemia. However, not all patients who are overweight have EFRMD, and not all patients with EFRMD are significantly overweight. The adipocentric paradigm provides the basis for a unifying, pathophysiological process whereby fat gain in susceptible patients leads to fat dysfunction ('sick fat'), and wherein pathological abnormalities in fat function (adiposopathy) are more directly related to the onset of EFRMD than increases in fat mass (adiposity) alone. But just as worsening fat function worsens EFRMD, improved fat function improves EFRMD. Peroxisome proliferator-activated receptor-gamma agonists increase the recruitment, proliferation and differentiation of preadipocytes ('healthy fat') and cause apoptosis of hypertrophic and dysfunctional (including visceral) adipocytes resulting in improved fat function and improved metabolic parameters associated with EFRMD. Weight loss interventions, such as a hypocaloric diet and physical exercise, in addition to agents such as orlistat, sibutramine and cannabinoid receptor antagonists, may have favorable effects upon fat storage (lipogenesis and fat distribution), nutrient metabolism (such as free fatty acids), favorable effects upon adipose tissue factors involved in metabolic processes and inflammation, and enhanced 'cross-talk' with other major organ systems. In some cases, weight loss therapeutic agents may even affect metabolic parameters and adipocyte function independently of weight loss alone, suggesting that the benefit of these agents in improving EFRMD may go beyond their efficacy in weight reduction. This review describes how adiposopathy interventions may affect fat function, and thus improve EFRMD.

[Plasma testosterone, obesity, metabolic syndrome and diabetes]

The frequency of diabetes and/or metabolic syndrome rises concurrently with that of body mass index (BMI). In adult men, plasma testosterone level changes evolve inversely to that of BMI. Plasma total testosterone, sex hormone-binding globulin (SHBG) and free testosterone are significantly lower in adult men with a clinical and biological pattern of metabolic syndrome (MetS) than in those without such a pattern. After adjustment for confounding factors, diabetes type 2 (DT2) remains associated with a significant decrease of plasma testosterone level. The androgenic blockade, used as a treatment for disseminated prostate cancer, induces a metabolic pattern similar to MetS. In men older than 65 years, a decrease of plasma testosterone level is associated with an increased risk of stroke or of death linked to a cardiovascular event. After exclusion of contraindications, the substitution with androgens of a demonstrated hypogonadism in a obese patient, notably when obesity is associated with a pattern of MetS and/or a DT2, could have some metabolic and cardiovascular advantages.

Comparing the effects of meal replacements with reduced-fat diet on weight, sexual and endothelial function, testosterone and quality of life in obese Asian men

Sexual dysfunction is more prevalent in obese than in normal-weight men. Meal replacements (MRs) are useful weight-loss strategies. We randomized obese (body mass index 27.5 kg m(-2), waist circumference (WC) 90 cm) Asian men (mean age 40.5 years, range 30-61) to a conventional reduced-fat diet (CD) (n=24) or MR-based plan (n=24) to reduce daily intake by 400 kcal for 12 weeks. There were significantly greater reductions in weight (4.2 ± 0.8 kg), WC (4.6 ± 0.7 cm), calorie and fat intake in the MR group, compared with the CD group (2.5 ± 0.4 kg, 2.6 ± 0.5 cm). Erectile function (International Index of Erectile Function 5-item score) improved comparably in the MR (3.4 ± 0.7 points) and CD (2.5 ± 0.5 points) groups, as did the Sexual Desire Inventory score (5.5 ± 2.3 vs 7.7 ± 2.1 points), quality of life (36-item Short Form survey score), plasma testosterone and endothelial function (Reactive Hyperemia Index). Subjects were switched to or continued CD for another 28 weeks. Weight, WC and erectile function were maintained at 40 weeks. MR induces greater reductions in weight and abdominal obesity than conventional diet, and comparable improvements in sexual and endothelial function, testosterone and quality of life.

Metabolic syndrome, circulating RBP4, testosterone, and SHBG predict weight regain at 6 months after weight loss in men

OBJECTIVE

Weight loss helps reduce the symptoms of the metabolic syndrome (MetS) in the obese, but weight regain after active weight loss is common. The changes and predictive role of circulating adipokines and sex hormones for weight regain in men during dietary intervention, and also the effect of basal MetS status on weight regain, were investigated.

DESIGN AND METHODS

Twenty-four men who continued to lose weight (WL) and 24 men who regained weight (WR) during the 6-month follow-up period after weight loss were selected from the Diogenes Study. Their circulating concentrations of leptin, adiponectin, retinol-binding protein 4 (RBP4), luteinizing hormone, prolactin, progesterone, total and free testosterone, and sex hormone-binding globulin (SHBG) were measured at baseline, after 8-week low-calorie diet-induced active weight loss, and after a subsequent 26-week ad libitum weight maintenance diet, and analyzed together with anthropometrical and physiological parameters.

RESULTS

Overweight and obese men with MetS at baseline had higher risk to regain weight (odds ratio = 2.8, P = 0.015). High baseline RBP4, low total testosterone, and low SHBG are predictors of weight loss regain (different between WR and WL with P = 0.001, 0.038, and 0.044, respectively).

CONCLUSIONS

These variables may play roles in the link between MetS and weight loss regain.

Changes in anthropometric measurements, body composition, blood pressure, lipid profile, and testosterone in patients participating in a low-energy dietary intervention

OBJECTIVE

The purpose of this study was to describe changes in anthropometric measurements, body composition, blood pressure, lipid profile, and testosterone following a low-energy-density dietary intervention plus regimented supplementation program.

METHODS

The study design was a pre-post intervention design without a control group. Normal participants were recruited from the faculty, staff, students, and community members from a chiropractic college to participate in a 21-day weight loss program. All participants (n = 49; 36 women, 13 men; 31 ± 10.3 years of age) received freshly prepared mostly vegan meals (breakfast, lunch, and dinner) that included 1200 to 1400 daily calories (5020.8 to 5857.6 J) for the women and 1600 to 1800 (6694.4 to 7531.2 J) daily calories for the men. Nutritional supplements containing enzymes that were intended to facilitate digestion, reduce cholesterol levels, increase metabolic rate, and mediate inflammatory processes were consumed 30 minutes before each meal. The regimented supplementation program included once-daily supplementation with a green drink that contained alfalfa, wheatgrass, apple cider vinegar, and fulvic acid throughout the study period. A cleanse supplementation containing magnesium, chia, flaxseed, lemon, camu camu, cat's claw, bentonite clay, tumeric, pau d'arco, chanca piedra, stevia, zeolite clay, slippery elm, garlic, ginger, peppermint, aloe, citrus bioflavonoids, and fulvic acid was added before each meal during week 2. During week 3, the cleanse supplementation was replaced with probiotic and prebiotic supplementation.

RESULTS

Multiple paired t tests detected clinically meaningful reductions in weight (- 8.7 ± 5.54 lb) (- 3.9 ± 2.5 kg), total cholesterol (- 30.0 ± 29.77 mg/dL), and low-density lipoprotein cholesterol (- 21.0 ± 25.20 mg/dL) (P < .05). There was a pre-post intervention increase in testosterone for men (111.0 ± 121.13 ng/dL, P < .05).

CONCLUSIONS

Weight loss and improvements in total cholesterol and low-density lipoprotein cholesterol levels occurred after a low-energy-density dietary intervention plus regimented supplementation program.

Improving metabolic health in obese male mice via diet and exercise restores embryo development and fetal growth

Paternal obesity is now clearly associated with or causal of impaired embryo and fetal development and reduced pregnancy rates in humans and rodents. This appears to be a result of reduced blastocyst potential. Whether these adverse embryo and fetal outcomes can be ameliorated by interventions to reduce paternal obesity has not been established. Here, male mice fed a high fat diet (HFD) to induce obesity were used, to determine if early embryo and fetal development is improved by interventions of diet (CD) and/or exercise to reduce adiposity and improve metabolism. Exercise and to a lesser extent CD in obese males improved embryo development rates, with increased cell to cell contacts in the compacting embryo measured by E-cadherin in exercise interventions and subsequently, increased blastocyst trophectoderm (TE), inner cell mass (ICM) and epiblast cell numbers. Implantation rates and fetal development from resulting blastocysts were also improved by exercise in obese males. Additionally, all interventions to obese males increased fetal weight, with CD alone and exercise alone, also increasing fetal crown-rump length. Measures of embryo and fetal development correlated with paternal measures of glycaemia, insulin action and serum lipids regardless of paternal adiposity or intervention, suggesting a link between paternal metabolic health and subsequent embryo and fetal development. This is the first study to show that improvements to metabolic health of obese males through diet and exercise can improve embryo and fetal development, suggesting such interventions are likely to improve offspring health.

Testosterone and insulin resistance in the metabolic syndrome and T2DM in men

Obesity, type 2 diabetes mellitus and the metabolic syndrome are major risk factors for cardiovascular disease. Studies have demonstrated an association between low levels of testosterone and the above insulin-resistant states, with a prevalence of hypogonadism of up to 50% in men with type 2 diabetes mellitus. Low levels of testosterone are also associated with an increased risk of all-cause and cardiovascular mortality. Hypogonadism and obesity share a bidirectional relationship as a result of the complex interplay between adipocytokines, proinflammatory cytokines and hypothalamic hormones that control the pituitary-testicular axis. Interventional studies have shown beneficial effects of testosterone on components of the metabolic syndrome, type 2 diabetes mellitus and other cardiovascular risk factors, including insulin resistance and high levels of cholesterol. Biochemical evidence indicates that testosterone is involved in promoting glucose utilization by stimulating glucose uptake, glycolysis and mitochondrial oxidative phosphorylation. Testosterone is also involved in lipid homeostasis in major insulin-responsive target tissues, such as liver, adipose tissue and skeletal muscle.

Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis

OBJECTIVE

Few randomized clinical studies have evaluated the impact of diet and physical activity on testosterone levels in obese men with conflicting results. Conversely, studies on bariatric surgery in men generally have shown an increase in testosterone levels. The aim of this study is to perform a systematic review and meta-analysis of available trials on the effect of body weight loss on sex hormones levels.

DESIGN

Meta-analysis.

METHODS

An extensive Medline search was performed including the following words: 'testosterone', 'diet', 'weight loss', 'bariatric surgery', and 'males'. The search was restricted to data from January 1, 1969 up to August 31, 2012.

RESULTS

Out of 266 retrieved articles, 24 were included in the study. Of the latter, 22 evaluated the effect of diet or bariatric surgery, whereas two compared diet and bariatric surgery. Overall, both a low-calorie diet and bariatric surgery are associated with a significant (P<0.0001) increase in plasma sex hormone-binding globulin-bound and -unbound testosterone levels (total testosterone (TT)), with bariatric surgery being more effective in comparison with the low-calorie diet (TT increase: 8.73 (6.51-10.95) vs 2.87 (1.68-4.07) for bariatric surgery and the low-calorie diet, respectively; both P<0.0001 vs baseline). Androgen rise is greater in those patients who lose more weight as well as in younger, non-diabetic subjects with a greater degree of obesity. Body weight loss is also associated with a decrease in estradiol and an increase in gonadotropins levels. Multiple regression analysis shows that the degree of body weight loss is the best determinant of TT rise (B=2.50±0.98, P=0.029).

CONCLUSIONS

These data show that weight loss is associated with an increase in both bound and unbound testosterone levels. The normalization of sex hormones induced by body weight loss is a possible mechanism contributing to the beneficial effects of surgery in morbid obesity.

The complex interaction between obesity, metabolic syndrome and reproductive axis: a narrative review

The aim of this narrative review is to provide current evidence for the interaction between obesity, metabolic syndrome (MS) and reproductive axis. Gonadotropin-releasing hormone (GnRH) pulses and, consequently, normal function of reproductive (hypothalamus-pituitary-gonadal) axis depend on normal energy balance, which presupposes sufficient food intake, reasonable energy consumption and average thermoregulatory costs. In case of an energy imbalance, reproductive dysfunction may occur. In young women, excessive leanness is accompanied by puberty delay, whereas premature puberty might be a manifestation of obesity. In a similar way, obesity in men affects fertility. Excess adipose tissue results in increased conversion of testosterone to estradiol, which may lead to secondary hypogonadism through reproductive axis suppression. Moreover, oxidative stress at the level of the testicular micro-environment may result in decreased spermatogenesis and sperm damage. Products of the adipocyte, such as leptin, adiponectin and resistin, and gut peptides, such as ghrelin, are considered to be crucial in the interaction between energy balance and reproduction. Finally, an indirect evidence for the interplay between MS and reproductive axis is the fact that when treating components of one, parameters of the other can be improved as well. These therapeutic interventions include lifestyle modifications, pharmacological agents, such as sex hormone replacement therapy, and surgical procedures. Although many issues remain unclear, the elucidation of the complex interaction between MS and reproductive axis will have obvious clinical implications in the therapeutic approach of both entities.

The impact of obesity on male reproduction: its biological significance

Since obesity and male subfertility have increased in parallel during the last decades, the hypothesis of an association between these two phenomena has been explored by several researchers. Although there is no consensus apparently obesity impacts men's reproductive potential by several mechanisms, like alterations on the hypothalamus-pituitary-testicular axis, modifications of spermatogenesis and semen quality and/or impairment of men's sexual health. This review intends to summarize the underlying bases of such alterations and propose new ones, without miscalculating their biological significance. Obesity is not rigorously related to subfertility; in addition, the existence of a genetic predisposition to obesity-linked sterility is currently under investigation. Nonetheless, the impact of obesity on male reproductive potential must be fully elucidated since the prevalence of obesity is increasing and consequently, the number of obese men with reduced fertility will also rise.

Sexual functioning and obesity: a review

We review the literature on the relationship between obesity and sexual functioning. Eleven population-based studies, 20 cross-sectional non-population-based studies, and 16 weight loss studies are reviewed. The consistency of findings suggests that the relationship between obesity and reduced sexual functioning is robust, despite diverse methods, instruments, and settings. In most population-based studies, erectile dysfunction (ED) is more common among obese men than among men of recommended weight. Studies of patients in clinical settings often include individuals with higher degrees of obesity, with most studies showing a relationship between obesity and lower levels of sexual functioning, especially ED. The few studies that include both genders generally report more problems among women. Most studies of patients with comorbidities associated with obesity also find an association between obesity and reduced sexual functioning. Most weight loss studies demonstrate improvement in sexual functioning concurrent with weight reduction despite varying study designs, weight loss methods, and follow-up periods. We recommend that future studies (i) investigate differences and similarities between men and women with respect to obesity and sexual functioning, (ii) use instruments that go beyond the assessment of sexual dysfunction to include additional concepts such as sexual satisfaction, interest, and arousal and, (iii) assess how and the degree to which obese individuals are affected by sexual difficulties. Given the high prevalence of obesity and the inverse association between body mass and sexual functioning, we also recommend that sexual functioning should be more fully addressed by clinicians, both in general practice and in weight loss programs.

What do most erectile dysfunction guidelines have in common? No evidence-based discussion or recommendation of heart-healthy lifestyle changes and/or Panax ginseng

Sexual health or erectile dysfunction (ED) state of the art guidelines provide a thorough overview of conventional prescription or other notable extrinsic treatment options. Yet, over the past 10-15 years, a plethora of international researchers have established that individual and comprehensive lifestyle changes can prevent and potentially improve ED. We review the lifestyle evidence that should equate to grade A or level 1 evidence recommendations for ED. We also review the evidence for Panax ginseng, an over-the-counter (OTC) dietary supplement with a 35-year history of laboratory investigations, multiple positive randomized trials over approximately 15 years and several independent meta-analyses and systematic reviews. Perhaps it is time to at least discuss and even emphasize lifestyle and other non-conventional interventions in ED guidelines so that patients can explore a diversity of potentially synergistic choices with their physicians and can improve their quality and quantity of life. Ignoring the consistent, positive data on lifestyle modifications in ED guidelines, for example, is tantamount to ignoring diet and lifestyle changes to reduce the risk of or ameliorate cardiovascular diseases.

Male fertility, obesity, and bariatric surgery

Obesity has become a new worldwide health problem with significant impact not only on cardiovascular diseases but also on many other related disorders, highlighting infertility. Obesity may adversely affect male reproduction by endocrinologic, thermal, genetic, and sexual mechanisms. There is good evidence that obesity can be associated with reduced sperm concentrations, but studies about sperm motility, morphology, and DNA fragmentation have been less numerous and more conflicting. Although weight loss is the cornerstone of the treatment of obesity-related infertility, with promising results in restoring fertility and normal hormonal profiles, bariatric surgery impact on male fertility is still unclear and until now there is not enough data to support the informed consent in this scenario. Physicians are encouraged to highlight possible positive and/or negative impacts concerning male capacity of fertilization when informing patients. A balanced judgment and a personalized case-by-case management with patient involvement in decisions are fundamental in this setting and indication of cryopreservation of semen samples should be considered in selected circumstances. Well-structured trials controlled for confounders including female factors and based on solid outcomes (ie, birth rates) must urgently come up to clarify this emerging scenario.

Diet and exercise in an obese mouse fed a high-fat diet improve metabolic health and reverse perturbed sperm function

Male obesity is associated with reduced sperm motility and morphology and increased sperm DNA damage and oxidative stress; however, the reversibility of these phenotypes has never been studied. Therefore, the aim of this study was to assess the reversibility of obesity and its associated sperm physiology and function in mice in response to weight loss through diet and exercise. C57BL6 male mice (n = 40) were fed either a control diet (CD; 6% fat) or a high-fat diet (HFD; 21% fat) for 10 wk before allocation to either diet and/or swimming exercise interventions for 8 wk. Diet alone reduced adiposity (1.6-fold) and serum cholesterol levels (1.7-fold, P < 0.05), while exercise alone did not alter these, but exercise plus diet also improved glucose tolerance (1.3-fold, P < 0.05). Diet and/or exercise improved sperm motility (1.2-fold) and morphology (1.1-fold, P < 0.05), and reduced sperm DNA damage (1.5-fold), reactive oxygen species (1.1-fold), and mitochondrial membrane potential (1.2-fold, P < 0.05) and increased sperm binding (1.4-fold) (P < 0.05). Sperm parameters were highly correlated with measures of glycemia, insulin action, and serum cholesterol (all P < 0.05) regardless of adiposity or intervention, suggesting a link between systemic metabolic status and sperm function. This is the first study to show that the abnormal sperm physiology resulting from obesity can be reversed through diet and exercise, even in the presence of ongoing obesity, suggesting that diet and lifestyle interventions could be a combined approach to target subfertility in overweight and obese men.

Association of baseline sex hormone levels with baseline and longitudinal changes in waist-to-hip ratio: Multi-Ethnic Study of Atherosclerosis

Objective

Waist-to-hip ratio (WHR) is strongly associated with prevalent atherosclerosis. We analyzed the associations of baseline serum levels of testosterone (T), estradiol (E2), sex hormone binding globulin (SHBG), and dehydroepiandrosterone (DHEA) with WHR in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort.

Subjects

Baseline data was available for 3144 men and 2038 postmenopausal women, who were non-users of hormone therapy, who were 45–84 years of age, and of White, Chinese, Black or Hispanic racial/ethnic groups. Of these, 2708 men and 1678 women also had longitudinal measurements of WHR measured at the second and/or the third study visits (median follow-up 578 days, and 1135 days, respectively).

Results

In cross-sectional analyses adjusted for age, race, and cardiovascular disease risk factors, T was negatively associated with baseline WHR in men, while in both sexes, E2 was positively associated and SHBG was negatively associated with WHR (all p<0.001). In longitudinal analyses, further adjusted for follow-up time and baseline WHR, baseline T was negatively associated with WHR at follow-up (p=0.001) in men, while in both sexes, E2 was positively associated (p=0.004), and SHBG was negatively associated with WHR (p<0.001). The longitudinal association of E2, but not T, was independent of SHBG. In both cross-sectional or longitudinal analyses, there were no associations between DHEA and WHR in either men or women.

Conclusion

Sex hormones are associated with WHR at baseline and also during follow-up above and beyond their baseline association. Future research is needed to determine if manipulation of hormones is associated with changes in central obesity.

Decreased serum testosterone levels in long-term adult survivors with fatty liver after childhood stem cell transplantation

Fatty liver and male gonadal dysfunction are potential late effects of therapy in adult survivors treated with stem cell transplantation (SCT) in childhood. Obesity and metabolic syndrome also are associated with low serum testosterone levels in the general population. However, the relationship between the degree of fatty liver and changes in serum testosterone levels in adult survivors has not been fully studied. We reviewed the clinical records of 34 male patients who received allogeneic SCT in childhood or adolescence. The median age at SCT was 10.0 years, and the median follow-up after SCT was 15.9 years. All but one patient showed no tendency toward overweight/obesity during the follow-up period. Fatty liver was diagnosed by ultrasound in 15 patients at 4 to 20 years after SCT. Patients who received cranial radiation therapy before SCT were more likely to develop fatty liver and insulin resistance. Moreover, fatty liver was statistically associated with decreased serum testosterone levels, whereas nonfatty liver was not (median, 527 ng/dL [range, 168-944 ng/dL] versus 302 ng/dL [165-698 ng/dL]; P < .0001). Changes in testosterone levels after SCT are affected not only by primary gonadal dysfunction but also by subsequent development or exacerbation of fatty liver.

Sperm parameters and male fertility after bariatric surgery: three case series

Recent studies have underlined the impact of obesity on sperm parameters, but very few data are available on the effect of weight loss on male fertility. This article reports the case series of three male patients who underwent rapid and major weight loss following bariatric surgery and the consequences of this surgery on semen parameters and fertility. A severe worsening of semen parameters was observed during the months after bariatric surgery, including extreme oligoasthenoteratozoospermia, but azoospermia was not observed. This effect may hypothetically be the result of two opposite mechanisms: (i) the suppression of the deleterious effects of obesity; and (ii) the negative impact of both nutritional deficiencies and the release of toxic substances. Information about potential reproductive consequences of bariatric surgery should be given to patients and sperm cryopreservation before surgery proposed. However, for one case, the alterations of spermatogenesis were reversible 2 years after the surgical procedure. Finally, intracytoplasmic sperm injection with fresh spermatozoa after male bariatric surgery can be successful, as demonstrated here, where clinical pregnancies were obtained for two out of the three couples.

Intentional weight loss and changes in symptoms of depression: a systematic review and meta-analysis

OBJECTIVE

Obesity is related to increased risk of several health complications, including depression. Many studies have reported improvements in mood with weight loss, but results have been equivocal. The present meta-analysis examined changes in symptoms of depression that were reported in trials of weight loss interventions. Between-groups comparisons of different weight loss methods (for example, lifestyle modification, diet-alone and pharmacotherapy) were examined, as were within-group changes for each treatment type.

METHOD

MEDLINE was searched for articles published between 1950 and January 2009. Several obesity-related terms were intersected with terms related to depression. Results were filtered to return only studies of human subjects, published in English. Of 5971 articles, 394 were randomized controlled trials. Articles were excluded if they did not report mean changes in weight or symptoms of depression, included children or persons with psychiatric disorders (other than depression), or provided insufficient data for analysis. Thirty-one studies (n=7937) were included. Two authors independently extracted a description of each study treatment, sample characteristics, assessment methods and changes in weight and symptoms of depression. Treatments were categorized as lifestyle modification, non-dieting, dietary counseling, diet-alone, exercise-alone, pharmacotherapy, placebo or control interventions.

RESULTS

Random effects models found that lifestyle modification was superior to control and non-dieting interventions for reducing symptoms of depression, and marginally better than dietary counseling and exercise-alone programs. Exercise-alone programs were superior to controls. No differences were found for comparisons of pharmacologic agents and placebos. Within-group analyses found significant reductions in symptoms of depression for nearly all active interventions. A meta-regression found no relationship between changes in weight and changes in symptoms of depression in lifestyle modification interventions.

CONCLUSIONS

On average, obese individuals in weight loss trials experienced reductions in symptoms of depression. Future studies should examine incidence and resolution of clinically significant depressive disorders with weight loss interventions.