Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Body Fat Distribution”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,297 records · Page 72Linked to original sources

Personality disorders in relation to anthropometric, endocrine and metabolic factors.

Subjects with abdominal obesity show several signs of a perturbed regulation of the hypothalamic-pituitary-adrenal (HPA) axis. This is known to occur after chronic, submissive stress. Perceived environmental stress is depending on personality characteristics. Therefore, personality disorders (PD:s) were examined in relation to HPA axis status, other endocrine and metabolic variables as well as anthropometry. Men (no.=284) aged 51 years, recruited in similar subgroups of low, median and high waist/hip circumference ratio (WHR) from a sample of 1302 men. Measurements of personality disorders by Structured Clinical Interview for DSM-III-R, Axis II (SCID II), body mass index (BMI, weight, kg/height2, m2), WHR and abdominal sagittal diameter (D), dexamethasone suppression test (0.5 mg, salivary measurements of cortisol), insulin-like growth factor I (IGF-I), testosterone and metabolic variables. Men with cluster A (paranoid, schizotypal, schizoid) PD showed an increased BMI, WHR and D, independent of dexamethasone suppression. Testosterone was decreased in these men in relation to a blunted dexamethasone suppression. BMI, WHR and D were increased in men with cluster B (borderline, histrionic, narcissistic) and cluster C (avoidant, dependent, obsessive compulsive, passive aggressive) PD, only in relation to a blunted dexamethasone suppression. Furthermore, IGF-I was low in cluster B. Metabolic variables were differently associated to clusters of PD but generally followed obesity. Path-analytic models suggested that cluster B and C PD were followed by blunted dexamethasone suppression and obesity. Men with cluster A PD showed centralized body fat distribution, independently of dexamethasone suppression. In contrast, men with impulsive (cluster B) and anxious (cluster C) personality disorders seem often to have abdominal obesity only in combination with a blunted dexamethasone suppression test, suggesting a HPA axis disturbance. These results suggest that PD:s are involved in the development of abdominal obesity in men, with different endocrine and metabolic profiles depending on the type of PD. This might hypothetically be due to frequent exposure and/or an increased sensitivity to environmental stress factors, caused by aberrant personalities.

Anthropometry↗

Relationship of androgenic activity to splanchnic insulin metabolism and peripheral glucose utilization in premenopausal women.

The importance of androgenic activity in mediating the effects of obesity and body fat topography on splanchnic insulin metabolism and peripheral insulin sensitivity was studied in 19 nonhirsute premenopausal women with a wide range of ideal body weight [percent ideal body weight (% IBW), 78-202%] and body fat distribution pattern [waist to hip girth ratio (WHR), 0.67-0.91]. Turnover kinetics of peripheral plasma C-peptide and insulin were measured, and estimates of pancreatic insulin production (PIP) and the hepatic extraction fraction (HEF) were calculated. The peripheral insulin sensitivity index (M/I) was determined during an euglycemic insulin clamp study. Androgenic activity was assessed by estimating the plasma level of sex hormone-binding globulin (SHBG) and percentage of free testosterone (% FT). After iv glucose stimulation, PIP ranged from 40-254 mU/min X m2 and correlated highly with % IBW (r = 0.78; P less than 0.01). Insulin HEF ranged from 5-69% of the pancreatic production and was inversely proportional to WHR (r = -0.60; P less than 0.01). Increasing WHR also correlated with the diminution in M/I (r = -0.47; P less than 0.05), which, in turn, correlated with the decline in the HEF of insulin (r = 0.60; P less than 0.01). Since PIP, HEF, and M/I correlated with SHBG and % FT, and since the degree of androgenic activity correlated with % IBW and WHR, partial regression analysis was performed. After adjusting for the effects of SHBG and % FT, the relationship between % IBW and PIP remained unaltered, whereas the correlation between WHR and HEF or M/I and their relationship to each other were either markedly reduced or became insignificant. Thus, in premenopausal women, the increase in pancreatic insulin production with increasing weight is independent of the degree of androgenic activity. On the other hand, the decline in hepatic insulin extraction and diminution in peripheral insulin sensitivity with upper body fat localization are in part mediated by increased androgenic activity. This association may account for the pronounced hyperinsulinemia and insulin resistance characteristic of this form of obesity.

Adipose Tissue↗

[Evaluation and treatment of obesity in clinical practice].

Obesity continues as before to be a widespread condition. Obesity is defined as a body weight of over 120% of the ideal weight, corresponding roughly to the 85th percentile of the weight distribution. According to the "Build Study" (1979), the ideal weight is assumed to be rather higher than formerly; in men it is 8%, in women 6% less than the so-called normal weight. The latter corresponds roughly to the average weight and is defined as: height (cm) minus 100 in kg. In obese subjects both somatic and psychological complications arise; these are related exponentially to the degree of overweight. More recent findings in the Framingham Study show that obesity leads to coronary heart disease and premature death independently of the classical risk factors. Evaluation of the patient should include a personal and familial history of the obesity, together with individual eating habits and the degree of physical activity indulged in. As assessment should be made of the body fat distribution (android or gynoid obesity); android obesity carries a relatively high risk. Complications should be looked for, together with other risk factors for arteriosclerosis. Treatment depends on the severity of the condition and on the motivation. In general, it should consist of a moderate reduction in the caloric value of the food intake together with advice on eating habits and an increase in bodily activity. Group therapy often gives good results on account of the dynamic interactions within groups. Patients with morbid obesity will profit from a very hypocaloric, "ketogenic" diet (ca. 600-700 kcal/day). One of the author's own studies showed that a very hypocaloric diet resulted in mood elevation and a reduction in the need for sleep. Conservative measures such dietary weight reduction, changes in eating habits and encouragement of bodily activity are to be preferred to surgical treatment (eg, gastric stapling). Weight reductions in hospital do not lead to a change in eating habits and are therefore of doubtful value; drug therapy as a form of long-term treatment is likewise of questionable usefulness.

Adult↗

LDL subclass phenotypes and the risk factors of the insulin resistance syndrome.

The insulin resistance syndrome is characterized by a constellation of risk factors including obesity, central body fat distribution, hypertension, glucose intolerance, elevated plasma insulin levels, increased triglyceride and decreased high-density lipoprotein (HDL) cholesterol. Similarly, low-density lipoprotein (LDL) subclass phenotype B, characterized by a predominance of small, dense LDL particles, is associated with increased triglyceride and lower HDL cholesterol levels. Both the insulin resistance syndrome and phenotype B have also been related to increased risk of coronary heart disease. Using a sample of nearly 700 women who participated in the Kaiser Permanente Women Twins Study, we investigated the associations of LDL subclass phenotype B with the risk factors that characterize the insulin resistance syndrome. The results demonstrate that LDL subclass phenotype B was strongly associated with both age and diabetes status. Among nondiabetic women, phenotype B was more prevalent in those with higher body mass index and in those with higher waist-hip ratio. In addition to the expected associations with triglyceride and HDL cholesterol, mean values of both systolic and diastolic blood pressure were higher in women with phenotype B. Finally, fasting and post-load insulin levels and post-load glucose levels were higher in those with phenotype B. In general, these relationships persisted in multivariate statistical analyses. Therefore, a predominance of small, dense LDL particles appears to be an integral feature of the risk factors that characterize the insulin resistance syndrome.

Adult↗

In vivo evidence of impaired peripheral fatty acid trapping in patients with human immunodeficiency virus-associated lipodystrophy.

The use of antiretroviral combination therapy in HIV has been associated with lipodystrophy and several metabolic risk factors. We postulated that patients with HIV-lipodystrophy have impaired adipose tissue free fatty acid (FFA) trapping and, consequently, increased hepatic FFA delivery. We investigated FFA, hydroxybutyric acid (HBA; reflecting hepatic FFA oxidation), and triglyceride (TG) changes after a high fat meal in HIV-infected males with (LIPO; n = 26) and without (NONLIPO; n = 12) lipodystrophy and in healthy males (n = 35). Because defective peripheral FFA trapping has been associated with impaired action of complement component 3 (C3), we also determined postprandial C3 concentrations. The LIPO group had higher homeostasis model assessment scores compared with the other groups. Areas under the curve (AUCs) for FFA, HBA, and TG were higher in the LIPO group than in the NONLIPO group or the controls. No differences in TG-AUC, FFA-AUC, and HBA-AUC were observed between the NONLIPO group and controls. In HIV-infected patients, FFA-AUC and HBA-AUC were inversely related to sc adipose tissue area. Plasma C3 showed a postprandial increase in healthy controls, but not in the HIV-infected groups. C3 was not related to body fat distribution, postprandial FFA, or HBA. The present data suggest disturbed postprandial FFA metabolism in patients with HIV-lipodystrophy, most likely due to inadequate incorporation of FFA into TG in sc adipose tissue, but do not support a major role for C3 in these patients. The higher postprandial HBA levels reflect increased hepatic FFA delivery and may aggravate insulin resistance and dyslipidemia, leading to increased cardiovascular risk.

Adolescent↗

Leisure-time physical activity, body size, and colon cancer in women. Nurses' Health Study Research Group.

BACKGROUND: Physical inactivity and high body mass index (weight in kilograms divided by height in square meters) have been linked to increased risk of colon cancer. However, none of the few prospective studies in women has shown a statistically significant reduction in colon cancer incidence or mortality associated with increased leisure-time physical activity. PURPOSE: In this prospective study, we asked whether leisure-time physical activity, body mass index, or body fat distribution could significantly influence the risk of colon cancer in women. METHODS: The participants in this study were enrolled in the Nurses' Health Study, which began in 1976. Every 2 years, the women provided additional personal information and information on medical risk factors and major medical events. The time spent per week at a variety of leisure-time physical activities was determined, and the time spent at each activity was multiplied by its typical energy expenditure, expressed in terms of metabolic equivalents or METs. The resulting values for each woman were added to yield an MET-hours-per-week score. Reported diagnoses of colon cancer were confirmed by review of hospital records and pathology reports. Relative risks and associated 95% confidence intervals were calculated. RESULTS: In multivariate analyses that included body mass index, women who expended more than 21 MET-hours per week on leisure-time physical activity had a relative risk of colon cancer of 0.54 (95% confidence interval [CI] = 0.33-0.90) in comparison with women who expended less than 2 MET-hours per week. Women who had a body mass index greater than 29 kg/m2 had a relative risk of colon cancer of 1.45 (95% CI = 1.02-2.07) in comparison with women who had a body mass index less than 21 kg/m2. A tendency toward higher colon cancer risk was observed for increasing waist-to-hip ratio (relative risk = 1.48 [95% CI = 0.88-2.49] for comparison of the highest quintile ratio [>0.833] to the lowest [<0.728]). CONCLUSIONS AND IMPLICATIONS: The significant inverse association between leisure-time physical activity and incidence of colon cancer in women in this study is consistent with what has been found in men. Recommendations to increase physical activity and maintain lean body weight should receive greater emphasis as part of a feasible approach to the prevention of colon cancer.

Adult↗

Insulin resistance and hypersecretion in obesity. European Group for the Study of Insulin Resistance (EGIR).

Insulin resistance and insulin hypersecretion are established features of obesity. Their prevalence, however, has only been inferred from plasma insulin concentrations. We measured insulin sensitivity (as the whole-body insulin-mediated glucose uptake) and fasting posthepatic insulin delivery rate (IDR) with the use of the euglycemic insulin clamp technique in a large group of obese subjects in the database of the European Group for the Study of Insulin Resistance (1,146 nondiabetic, normotensive Caucasian men and women aged 18-85 yr, with a body mass index (BMI) ranging from 15 to 55 kg.m-2). Insulin resistance, defined as the lowest decile of insulin sensitivity in the lean subgroup (608 subjects with a mean BMI of 29 kg.m-2). Insulin sensitivity declined linearly with BMI at an age- and sex-adjusted rate of 1.2 micromol.min-1.kg FFM-1 per BMI unit (95% confidence intervals = 1.0-1.4). Insulin hypersecretion, defined as the upper decile of IDR, was significantly (P<0.0001) more prevalent (38%) than insulin resistance in the obese group. In the whole dataset, IDR rose as a function of both BMI and insulin resistance in a nonlinear fashion. Neither the waist circumference nor the waist-to-hip ratio, indices of body fat distribution, was related to insulin sensitivity after adjustment for age, gender, and BMI; both, however, were positively associated (P<0.001) with insulin hypersecretion, particularly in women. In nondiabetic, normotensive obese subjects, the prevalence of insulin resistance is relatively low, and is exceeded by the prevalence of insulin hypersecretion, particularly in women with central obesity. In the obese with preserved insulin sensitivity, risk for diabetes, cardiovascular risk, and response to treatment may be different than in insulin resistant obesity.

Adolescent↗

[Adiposity distribution in adolescents by conicity index].

Body regional fat distribution has been linked with a metabolic atherogenic risk profile, that starts early in life. Data from a cross-sectional sample of 394 boys and girls, 11 to 16 years, who inhabit a slum sector of Caracas, Venezuela was studied using Conicity Index (C): [equation: see text] by means of Box-plot diagram, Levene, ANOVA, and Scheffé tests. The accepted level of significance was p < 0.05. Results showed significant differences in body fat distribution between age groups. Height and body mass index were used as control variables. C values ranged between (1.02-1.18) in boys and (0.99-1.14) in girls. Boys attained higher mean values. All groups showed variance homogeneity (p value > 0.05) and sexual dimorphism was found at 11, 12 and 13 years, that were removed after controlling for height and body mass index. Differences according to age groups in boys, were removed after controlling for height. Results found conicity index as an alternative method to assess abdominal fat distribution during adolescents years.

Adipose Tissue↗

Metabolic, anthropometric, and psychological characteristics of obese binge eaters.

This study examined the relationship of binge eating to a variety of metabolic, anthropometric, and psychological characteristics in 132 obese women seeking weight reduction. Contrary to findings of a reduced resting metabolic rate (RMR) in persons with bulimia nervosa, no significant differences were observed between obese bingers and nonbingers in RMR or thyroid hormones. Nor did the two groups differ significantly in weight, percentage body fat, body fat distribution, or serum lipid levels. Consistent with previous findings, however, binge eaters did score significantly higher in depression and other measures of psychopathology, as assessed by the Minnesota Multiphasic Personality Inventory. They also scored significantly higher in disinhibition and hunger but significantly lower in cognitive restraint. All of these findings await confirmation in subjects diagnosed according to criteria proposed for a new binge eating disorder. The present results, however, provide little support for the hypothesis that binge eating in obese individuals is related to reduced resting energy requirements.

Adult↗

Reproducibility of insulin sensitivity measured by the minimal model method.

Insulin resistance is a critical component underlying the altered glucose homeostasis in a variety of metabolic and non-metabolic disorders. Aging, body fat distribution, obesity, diabetes mellitus or hypertension are well recognized conditions associated with an impaired tissue sensitivity to insulin action. Apart from such constant factors, insulin sensitivity can be acutely modified by independent variables such as physical exercise, dietary factors, alcohol intake or harmless drugs. To evaluate the day-to-day intra-individual variation in insulin sensitivity, glucose homeostasis and lipid profiles, we investigated the insulin sensitivity index (S1) (determined by the minimal model method of Bergman), basal and post-glucose-load insulin and glucose levels, serum total triglyceride and lipoprotein cholesterol fractions in 15 healthy young men (24 +/- 1 year, mean +/- SEM), on two different occasions at an interval of 3 weeks (days 1 and 21), after 3 days of a standard dietary regimen and after an overnight fast. Blood pressure, heart rate, body weight and 24 h urinary sodium excretion were almost identical in the two phases. S1(day 1) varied from 4.2 to 15.8 x 10(-4).min-1 pro microU/ml (mean: 10.2 +/- 0.9) and correlated with S1(day 21) (11.2 +/- 1.2 x 10(-4).min-1 pro microU/ml, r = 0.78, p less than 0.0007). The slope of the relationship did not differ from 1 (1.01, p greater than 0.90), the intercept was close to the origin (0.8, p greater than 0.73) and the coefficient of variation was 14.4%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Insulin and leptin concentrations in obese humans during long-term weight loss.

BACKGROUND: Leptin is likely to be involved in the homeostasis of body weight. Insulin is suggested to regulate both short-term and long-term circulating leptin levels. The present study aims to assess the relation between insulin and leptin levels in obese humans. METHODS: Some 53 obese subjects (body mass index 35.1 +/- 3.9 kg m-2 (mean +/- SD)) were prescribed a hypocaloric diet and randomized to either a placebo or the intestinal lipase inhibitor orlistat for 2 years. Serum leptin and insulin levels were determined repeatedly during these 2 years (5 times in the fasting condition and twice after an oral glucose load). RESULTS: Leptin concentrations appeared to be regulated at a specific level for each individual throughout the weight-loss period. The BMI explained 39.7% of the total variance in leptin levels, the body-fat distribution 17.2%, individual characteristics 30.3%; and the fasting serum insulin concentration 1.0%. After a mean weight loss of 7.7 +/- 4.9 kg, the time-integrated insulin response to an oral glucose load was significantly lower but the leptin response remained unchanged. CONCLUSIONS: The BMI is the main determinant of the circulating leptin concentration in obese humans. Individual characteristics seem to determine the leptin level, given the BMI. In a short-term observational study in obese humans, changes of insulin levels do not appear to be correlated to changes in leptin levels.

Adult↗

Imaging techniques for measuring adipose-tissue distribution in the abdomen: a comparison between computed tomography and 1.5-tesla magnetic resonance spin-echo imaging.

Eight subjects were examined both by abdominal X-ray computed transverse axial tomography (CT) and magnetic resonance imaging (MRI) (SE) (TR/TE, 200 ms/15 ms); another eight volunteers were subjected to three MRI scans to test the reliability of repeated measures. Correlations between fat area measures obtained by CT and by MRI for subcutaneous fat, total fat, and visceral vs. subcutaneous-fat ratio were highly significant (r = 0.93, 0.91, and 0.94, respectively; p < 0.01), and the standard errors of estimation were 9.99, 23.87, and 0.0047. The average errors of the method for different fat areas were 2.20 cm2 (intra-examination variance) and 3.75 cm2 (inter-examination variance) for visceral and 0.82 cm2 (intra-examination variance) and 1.29 cm2 (inter-examination variance) for subcutaneous fat areas, respectively. These results suggest that SE MRI is a practical approach to evaluate body fat distribution without the exposure to radiation. The reproducibility of SE MRI for the determination of fat areas is high; variation is small and acceptable. However, it is difficult to determine which estimate of fat area should be accepted when there is a discrepancy between MRI and CT measures.

Adipose Tissue↗

Effects of sibutramine on abdominal fat mass, insulin resistance and blood pressure in obese hypertensive patients.

OBJECTIVE: The objective of this study is to assess the effects of sibutramine on body weight, body fat distribution, insulin resistance, plasma leptin, lipid profile and blood pressure profiles in hypertensive obese patients. METHODS: Eighty-six central obese hypertensive patients (BMI = 39 +/- 5 kg/m(2), 84% of women, 48 +/- 8.5 years old) were placed on a hypocaloric diet and placebo therapy for 4 weeks. They were then randomized to receive sibutramine (10 mg) or placebo for 24 weeks. Both, before therapy and at the end of the study, the waist and hip circumferences were measured and the waist/hip ratio (WHR) was calculated; abdominal ultrasonography was performed in order to estimate the amount of subcutaneous fat (SF) and visceral fat (VF), and the visceral/subcutaneous ratio. Beyond HOMA-r, another insulin resistance index (IRIp) was calculated by means of the formula: peak of blood glucose after oral glucose load x plasma insulin level/10(4). Fasting plasma leptin and lipid levels were also determined. RESULTS: Sibutramine induced greater weight reduction than placebo (6.7 vs. 2.5%, p < 0.001). Reductions in WHR (0.97 +/- 0.08 vs. 0.94 +/- 0.07, p < 0.01), IRIp (0.11 +/- 0.07 vs. 0.09 +/- 0.06 mmol mu/l(2)) and VF (6.4 +/- 2.4-6.0 +/- 2.4 cm, p < 0.01) were observed only with sibutramine. Plasma leptin decreased with placebo (24 +/- 15 vs. 18 +/- 10 UI/l, p < 0.01), but not with sibutramine (18.8 +/- 8.4 vs. 18.2 +/- 13.2 UI/l). No clinically significant change in lipid profile was observed in both groups. Moreover, office and 24-h blood pressure values did not change during placebo or sibutramine therapy, whereas a significant increase in office heart rate, from 78.3 +/- 7.3-82 +/- 7.9 b.p.m., p = 0.02, was observed with sibutramine. CONCLUSIONS: Sibutramine therapy induced greater body weight loss than placebo in hypertensive obese patients. This was associated with WHR reduction, decreases in VF and insulin resistance. The maintenance of leptin levels during sibutramine therapy may be important to avoid weight recovery, although this finding must be confirmed by other prospective studies.

Adult↗

Prevalence of hypertension in HIV-positive patients on highly active retroviral therapy (HAART) compared with HAART-naïve and HIV-negative controls: results from a Norwegian study of 721 patients.

Highly active antiretroviral therapy (HAART) may induce dyslipidemia, insulin resistance and body fat distribution similar to that seen in the metabolic syndrome. Hypertension is often a part of the classic metabolic syndrome, but few studies are published about hypertension in HIV-positive patients on HAART. The aim of this study was to compare the prevalence of hypertension in HIV-positive patients on HAART with that in HIV-positive/HAART-naïve patients and HIV-negative controls. The cross-sectional study included 283 unselected HIV-positive ambulatory patients, 219 who were on HAART and 64 who were HAART-naïve. Age- and gender-matched controls (n=438) were randomly selected from a simultaneous health survey of the general population. The prevalence of hypertension was 21% in patients on HAART, 13% in HAART-naïve patients (P=0.20), and 24% in HIV-negative controls (P=0.28). Among several possible risk factors for hypertension, only body mass index (BMI) was found to be a confounder. BMI was similar in HAART-treated and HAART-naïve patients but elevated in controls compared to HAART-treated patients. After adjustment for BMI, the prevalence of hypertension in HIV-negative controls was slightly lower than that in patients on HAART (P=0.29). The results demonstrated a prevalence of hypertension in patients on HAART similar to that in HIV-negative controls. The prevalence of hypertension was somewhat higher in patients on HAART compared to HAART-naïve patients, but the difference was not statistically significant. Considering the marked drop in mortality following antiretroviral therapy, we conclude that the possible influence of HAART on the prevalence of hypertension appears to be a minor problem.

Adult↗

The effects of weight loss treatments on upper and lower body fat.

The intra-abdominal visceral deposition of adipose tissue, which characterises upper body obesity, is a major contributor to the development of hypertension, glucose intolerance and hyperlipidaemia. Conversely, individuals with lower body obesity may have comparable amounts of adipose tissue but remain relatively free from the metabolic consequences of obesity. This raises an obvious question-are there particular weight reducing treatments which specifically target intra-abdominal fat? In theory, surgical removal of upper body fat should be effective. In reality, neither liposuction nor apronectomy ('tummy tuck') have any beneficial metabolic effects, they simply remove subcutaneous adipose tissue which is often rapidly replaced. Vertical banded gastroplasty and gastric bypass operations may be dramatically effective in improving blood pressure, insulin sensitivity and glucose tolerance. However, these benefits result from a parallel reduction in visceral and total body fat. Studies of body fat distribution in postmenopausal women confirm that the marked decrease in adiposity, following a programme of very low calorie diet and exercise, reflects a comparable reduction in visceral and thigh fat. The reduction in waist circumference after a low fat/exercise programme suggests a similar situation in men. Exercise has an important role in treatment but, once again, the fat loss is generalised. Nevertheless, the improved metabolic parameters seen in exercising obese subjects, independent of weight loss, suggest other beneficial actions. Growth hormone (GH) has a marked lipolytic action. GH replacement treatment for GH deficient adults with pronounced abdominal fat deposition, has been shown to reduce intra-abdominal fat by 47% compared to 27% decrease in abdominal subcutaneous fat. Similar beneficial actions on abdominal fat have been reported following treatment with testosterone in obese men. The potential hazards of such treatments make them unsuitable therapy for obesity. Dexfenfluramine is effective in reducing total body fat but the results from a six month randomised controlled trial indicates that it does not specifically influence changes in waist circumference associated with weight loss. In conclusion, any treatment which reduces total body fat will, by its nature, reduce intra-abdominal visceral fat. There are presently no specific treatments which can be recommended for intra-abdominal fat but increasing knowledge of the biochemical aberrations associated with visceral adiposity may lead to more specific therapies for the future.

Abdomen↗

Glucocorticoids and neuroendocrine function.

Recent experimental evidence supports the role of glucocorticoids in the neuroendocrine control of food intake and energy expenditure. In particular, glucocorticoids promote food consumption directly through stimulation of NPY and inhibition of CRH and melanocortin release. CRH and NPY are also functionally linked by a mutual regulation. CRH is anorexigenic when secreted acutely while it exerts the opposite effect when, upon sustained secretion, it stimulates the hypothalamo-pituitary-adrenal (HPA) axis. The orexigenic effects of glucocorticoids are counteracted by a steroid-induced rise in leptin levels that closes a regulatory loop regarding food consumption. Furthermore, glucocorticoids may alter body fat distribution, increasing truncal adiposity both directly and by inhibition of growth hormone secretion. No clearcut alterations of the HPA function are apparent in obesity as a whole. However, subtle and specific abnormalities may be noted in subsets of obese patients. Indeed, obesity, mostly visceral type, is associated with an increased cortisol clearance and 11-beta hydroxysteroid dehydrogenase activity in the omental fat. In the same vein, an increased cortisol rise following a mixed meal has been observed in obese subjects. Finally, it has been proposed that adrenal incidentalomas, often characterized by enhanced cortisol secretion, might be a clinical expression of the X syndrome.

Animals↗

Preventing obesity in black women by targeting adolescents: a literature review.

Obesity is a critical problem in black women. Black women have been found to have twice the rate of obesity of white women, and the origins of obesity appear to be in adolescence. To date, few obesity prevention and treatment programs have been designed specifically for black female adolescents and black women. In this review, the biopsychosocial factors surrounding obesity in the black female population are discussed, including the significance of body fat distribution for the development of diseases common to the black population, such as diabetes and hypertension; the cultural tolerance for overweight and obesity in black women; and the importance of family and social networks in the dissemination of health information. Programs that stress early intervention during adolescence are identified as having the most potential to make an impact on obesity in black women and, ultimately, to reduce chronic disease. However, such interventions must be sensitive to cultural belief systems and values. The need to eliminate a predominantly white, Anglo-Saxon, ethnocentric viewpoint to prevent and treat obesity in black female adolescents is stressed.

Adolescent↗

Training status, resting metabolic rate, and cardiovascular disease risk in middle-aged men.

We investigated differences in resting metabolic rate (RMR) and cardiovascular disease risk factors among 86 middle-aged men (36 to 59 years) classified as resistance-trained ([RT] n = 19), aerobic-trained ([AT] n = 37), or untrained ([UT], n = 30) according to habitual exercise patterns. RMR, body composition, body fat distribution, supine blood pressure, maximal aerobic capacity (VO2max), plasma lipid levels, and fasting levels of insulin, glucose, and thyroid hormones were measured. We found that RMR, adjusted for differences in fat-free mass, showed a tendency to be greater in AT men as compared with RT men (P = .09) and was greater in AT men as compared with UT men (P < .05). No differences in RMR were noted between RT and UT men. UT men had higher values for total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), and the insulin to glucose ratio and lower values for high-density lipoprotein cholesterol (HDL-C) (all P < .01) as compared with RT and AT men, whereas no differences in these variables were noted between RT and AT men. Supine diastolic blood pressure was lower in RT men as compared with both AT and UT men. Stepwise regression analysis showed that variations in body fatness accounted for the greatest variation in fasting lipid profile, blood pressure, and the insulin to glucose ratio among groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗