bluuebunny/crossref_metadata_2025 huggingface dataset:
Federal Communication about Obesity in the Dietary Guidelines and Checkoff Programs
Authors: Wilde Parke E.
Published: April 2008

The new Dietary Guidelines for Americans focus on obesity prevention. They recommend increased consumption of whole grains, fruits, vegetables, fish, and low‐fat dairy products, within a balanced diet whose total calories have been moderately reduced. Meanwhile, other well‐known and well‐funded federally sponsored consumer communications promote increased total consumption of beef, pork, and dairy products, including energy dense foods such as bacon cheeseburgers, barbecue pork ribs, pizza, and butter. These latter communications are sponsored by the federal government's commodity promotion programs, known as “checkoff” programs. The programs are established by Congress, approved by a majority of the commodity's producers, managed jointly by a producer board and the U.S. Department of Agriculture, and funded through a tax on the producers. The federal government enforces the collection of more than $600 million annually in mandatory assessments, approves the advertising and marketing programs, and defends checkoff communication in court as the federal government's own message—in legal jargon, as its own “government speech.” Federal support for promoting fruits and vegetables is small by comparison. The checkoff programs recently have become more clearly identified as federal programs. After a recent decision by the U.S. Supreme Court upholding the constitutionality of the checkoff programs, calls for consistency with the Dietary Guidelines may get louder. The current inconsistencies in federal communication undermine the effectiveness of the Dietary Guidelines as an antidote to the shortcomings of the private sector market for information about weight and obesity.
Adipose Gene Expression Response of Lean and Obese Mice to Short‐term Dietary Restriction
Authors: van Schothorst Evert M. , Keijer Jaap , Pennings Jeroen L. A. , Opperhuizen Antoon , van, Den Brom Charissa E. , Kohl Thomas , Hal Nicole L. W. Franssen‐van , Hoebee Barbara
Published: April 2008

Overweight and obesity lead to higher morbidity risks, which are alleviated even by mild weight loss. To gain insight in the molecular effects of weight loss in adipose tissue, we analyzed the effects of short‐term dietary restriction (DR) on mice fed a low‐fat diet (lean mice) or a high‐fat diet (obese mice). Female C57Bl6/J mice on both diets were on DR until an average body weight loss of 20%, which was achieved in 8 to 12 days depending on body weight at the start of DR. Plasma free fatty acids and blood glucose levels decreased significantly on DR. In the (restricted) low‐fat diet groups, gene expression analysis using adipose‐enriched cDNA microarrays revealed only two transcripts to be significant differentially expressed by DR: up‐regulation of malic enzyme (Mod1) and down‐regulation of major urinary protein 1 (Mup1). Real‐time polymerase chain reaction analysis confirmed these findings and showed, for the high‐fat diet groups, an identical expression pattern for Mup1, whereas Mod1 showed an opposed gene expression pattern for the high‐fat diet groups. In conclusion, initial weight loss induces transcriptional changes only in a very small number of adipose genes, which also depends on the (restricted) diet used.
HIV Protease Inhibitor‐Specific Alterations in Human Adipocyte Differentiation and Metabolism
Authors: Kim Roy J. , Wilson Camella G. , Wabitsch Martin , Lazar Mitchell A. , Steppan Claire M.
Published: April 2008

Objective: Human immunodeficiency virus (HIV) patients on antiretroviral regimens frequently develop a syndrome of abnormal fat distribution, insulin resistance, and dyslipidemia. This lipodystrophic syndrome has been most closely linked to the use of HIV protease inhibitors (PIs). Several mechanisms have been postulated to explain these adverse effects of PIs, based largely on studies of rodent adipocytes. Intriguingly, atazanavir, a newer PI equally effective against HIV, is associated with fewer signs of lipodystrophy. We hypothesized that the less deleterious clinical effects of atazanavir would be reflected in physiological differences observed in PI‐treated adipocytes.

Research Methods and Procedures: We compared the effects of atazanavir and an older PI associated with lipodystrophy, ritonavir, on differentiation, gene expression, adipocytokine secretion, and insulin signaling in a human adipocyte cell line.

Results: Ritonavir inhibited human adipocyte differentiation and induced apoptosis to a greater extent than atazanavir. Treatment of mature adipocytes with ritonavir, but not atazanavir, also selectively decreased insulin signaling. Moreover, ritonavir also selectively decreased expression of adiponectin, an insulin‐sensitizing adipocytokine, while inducing interleukin‐6, a proinflammatory cytokine implicated in insulin resistance.

Discussion: These data suggest that the distinct metabolic side effect profiles of these PIs could be a consequence of their differential effects on adipocyte physiology.
Ethnic Differences in Body Composition and Other Markers of Cardiovascular Disease Risk: Study in Matched Haitian and White Subjects from Quebec
Authors: Désilets Marie‐Claude , Garrel Dominique , Couillard Charles , Tremblay Angelo , Després Jean‐Pierre , Bouchard Claude , Delisle Hélène
Published: April 2008

Objectives: People of African descent may be at greater risk of metabolic syndrome (MS) compared with whites. We examined the associations among MS markers, body composition, and resting metabolic rate (RMR) in black Haitians and in white subjects living in Quebec, Canada.

Research Methods and Procedures: Forty randomly selected Haitians were matched with 40 white subjects for age, sex, and BMI. Glycemic status and insulin resistance were assessed based on a 3‐hour glucose tolerance test. Blood lipids, blood pressure, abdominal fat (computed tomography), and waist circumference (WC) were measured. RMR was estimated by indirect calorimetry.

Results: Triglycerides were significantly correlated with blood pressure only in Haitians and with the area under the curve for insulin only in whites. Haitians had significantly (p < 0.05) lower triglycerides and higher high‐density lipoprotein‐cholesterol concentrations but higher blood pressure than whites at any given WC value. General linear models showed that Haitians had less visceral adipose tissue than whites for the same WC. RMR was lower among Haitians for any given value of BMI or WC than in whites. Also, WC was more strongly associated with glucose area under the curve and to log‐homeostasis model assessment in white than in Haitian subjects.

Discussion: The MS may be ethnospecific in its features and etiology. The standard anthropometric indices of obesity may not be as effective in populations of African descent compared with whites, unless appropriate cut‐off values are defined.
Trends in Overweight from 1980 through 2001 among Preschool‐Aged Children Enrolled in a Health Maintenance Organization
Authors: Kim Juhee , Peterson Karen E. , Scanlon Kelley S. , Fitzmaurice Garrett M. , Must Aviva , Oken Emily , Rifas‐Shiman Sheryl L. , Rich‐Edwards Janet W. , Gillman Matthew W.
Published: April 2008

Objective: To examine overweight trends over a 22‐year period among preschool‐aged children from primarily middle‐income families enrolled in a health maintenance organization.

Research Methods and Procedures: From well‐child care visits to a Massachusetts health maintenance organization, we randomly selected one visit per child per calendar year, yielding a study sample of 120,680 children seen at 366,109 visits from 1980 through 2001. Using multivariate logistic regression models accounting for repeated observations of individual children across years, we estimated trends in prevalence of overweight (weight‐for‐length/height ≥ 95th percentile) and at‐risk‐for‐overweight (85th to 95th percentile).

Results: Over the 22‐year study period, the observed prevalence of overweight increased from 6.3% to 10.0% and at‐risk‐for‐overweight increased from 11.1% to 14.4%. These increases were evident among all groups of children including infants < 6 months of age. Overall, the adjusted odds ratios were 1.21 per decade (95% confidence interval, 1.17 to 1.25) for overweight and 1.06 per decade (95% confidence interval, 1.03 to 1.08) for at‐risk‐for‐overweight.

Discussion: Rates of overweight are increasing in very young children, even infants, from primarily middle‐class families.
Effect of Circulatory Congestion on the Components of Pulmonary Diffusing Capacity in Morbid Obesity
Authors: Oppenheimer Beno W. , Berger Kenneth I. , Rennert Douglas A. , Pierson Richard N. , Norman Robert G. , Rapoport David M. , Kral John G. , Goldring Roberta M.
Published: April 2008

Objective: Obese patients without clinically apparent heart disease may have a high output state and elevated total and central blood volumes. Central circulatory congestion should result in elevated pulmonary diffusing capacity (DLCO) and capillary blood volume (Vc) reflecting pulmonary capillary recruitment; however, the effect on membrane diffusion (Dm) is uncertain. We examined DLCO and its partition into Vc and Dm in 13 severely obese subjects (BMI = 51 ± 14 kg/m2) without manifest cardiopulmonary disease before and after surgically induced weight loss.

Research Methods and Procedures: DLCO and its partition into Vc and Dm [referenced to alveolar volume (VA)] as described by Roughton and Forster, total body water by tritiated water, and fat distribution by waist‐to‐hip ratio were performed.

Results: Despite normal DLCO (mean 98 ± 16% predicted), Vc/VA was increased (mean 118 ± 30% predicted), and Dm/VA was reduced (mean 77 ± 34% predicted). Nine of 13 subjects were restudied after weight loss (mean 52 ± 43 kg); Vc/VA decreased to 89 ± 18% predicted (p = 0.01), and Dm/VA increased to 139 ± 30% predicted (p < 0.01). Increasing total body water was associated with both increasing Vc (r = 0.74, p = 0.01) and increasing waist‐to‐hip ratio (r = 0.65, p = 0.02), indicating that circulatory congestion increases with increasing central obesity.

Discussion: Severely obese subjects without manifest cardiopulmonary disease may have increased Vc indicating central circulatory congestion and reduced Dm suggesting associated alveolar capillary leak, despite normal DLCO. Reversibility with weight loss is in accord with reversibility of the hemodynamic abnormalities of obesity.
Two‐dimensional Predictive Equation to Classify Visceral Obesity in Clinical Practice
Authors: Garaulet Marta , Hernández‐Morante Juan J. , Tébar Francisco J. , Zamora Salvador , Canteras Manuel
Published: April 2008

Objective: Visceral obesity assessment is not easy, and although computed tomography (CT) is an accurate tool, this technique is expensive and sometimes not suitable in clinical practice. We developed a new two‐dimensional elliptical anthropometric equation to classify visceral obesity and evaluated the validity and the reliability of the new equation compared with CT.

Research Methods and Procedures: We collected anthropometric and CT data from overweight/obese subjects (n = 61, BMI = 32.4 ± 3.7 kg/m2). A validation group of 32 subjects was also selected. An equation for the assessment of visceral obesity was developed using multiple regression analysis. Once validated, the equation was compared with previous models. Tests for accuracy included mean differences, analysis of diagnostic, R2, Snedecor's F‐test, and Bland‐Altman plot.

Results: Multiple regression analysis revealed that the sagittal and coronal diameters and the triceps skinfold were significant contributors to the model. The final equation was: visceral area (VA)/subcutaneous area (SA)predicted = 0.868 + 0.064 × sagittal diameter −0.036 × coronal diameter −0.022 × triceps skinfold. Patients with visceral‐subcutaneous area ratio (VA/SA) >0.42 were classified as having visceral obesity. The predictive equation was valid, showing a significant association with VA/SA assessed by CT (VA/SACT; r = 0.68; p < 0.0001). Paired Student's t test showed no significant differences with VA/SACT (p = 0.541). The reliability was high [F(24/60) = 2.12; p = 0.01].

Discussion: The new two‐dimensional and elliptical predictive equation is valid to assess visceral obesity and is more precise than previous models.
Genetic Effects on Obesity Assessed by Bivariate Genome Scan: The Mexican‐American Coronary Artery Disease Study
Authors: Li Xiaohui , Quiñones Manuel J. , Wang Dai , Bulnes‐Enriquez Isabel , Jimenez Xochitl , De, La Rosa Roxana , Aurea George L. , Taylor Kent D. , Hsueh Willa A. , Rotter Jerome I. , Yang Huiying
Published: April 2008

Objective: To identify the genetic determinants of obesity using univariate and bivariate models in a genome scan.

Research Methods and Procedures: We evaluated the genetic and environmental effects and performed a genome‐wide linkage analysis of obesity‐related traits in 478 subjects from 105 Mexican‐American nuclear families ascertained through a proband with documented coronary artery disease. The available obesity traits include BMI, body surface area (BSA), waist‐to‐hip ratio (WHR), and trunk fat mass as percentage of body weight. Heritability estimates and multipoint linkage analysis were performed using a variance components procedure implemented in SOLAR software.

Results: The heritability estimates were 0.62 for BMI, 0.73 for BSA, 0.40 for WHR, and 0.38 for trunk fat mass as percentage of body weight. Using a bivariate genetic model, we observed significant genetic correlations between BMI and other obesity‐related traits (all p < 0.01). Evidence for univariate linkage was observed at 252 to approximately 267 cM on chromosome 2 for three obesity‐related traits (except for WHR) and at 163 to approximately 167 cM on chromosome 5 for BMI and BSA, with the maximum logarithm of the odds ratio score of 3.12 (empirical p value, 0.002) for BSA on chromosome 2. Use of the bivariate linkage model yielded an additional peak (logarithm of the odds ratio = 3.25, empirical p value, 0.002) at 25 cM on chromosome 7 for the pair of BMI and BSA.

Discussion: The evidence for linkage on chromosomes 2q36‐37 and 5q36 is supported both by univariate and bivariate analysis, and an additional linkage peak at 7p15 was identified by the bivariate model. This suggests that use of the bivariate model provides additional information to identify linkage of genes responsible for obesity‐related traits.
The Importance of Catch‐up Growth after Early Malnutrition for the Programming of Obesity in Male Rat
Authors: Bieswal Florence , Ahn Marie‐Thérèse , Reusens Brigitte , Holvoet Paul , Raes Martine , Rees William D. , Remacle Claude
Published: April 2008

Objective: To investigate whether catch‐up growth after maternal malnutrition would favor the development of obesity in adulthood.

Research Methods and Procedures: Pregnant rats were submitted to protein or calorie restriction during the course of gestation. During lactation, pups were protein‐restricted, normally fed, or overfed [reduced litter size, control (C) diet]. At weaning, rats were transferred to chow or to a hypercaloric diet (HCD) known to induce obesity. Body weight, food intake, blood parameters, glucose tolerance, adipocyte cellularity, and adipose factors contributing to cardiovascular disease development were measured.

Results: Protein and calorie restriction during gestation led to growth retardation at birth. If malnutrition was prolonged throughout lactation, adult body weight was permanently reduced. However, growth‐retarded offspring overfed during the suckling period underwent a rapid catch‐up growth and became heavier than the normally fed Cs. Offspring of calorie‐restricted rats gained more weight than those of dams fed protein‐restricted diet. Feeding an HCD postnatally amplified the effect of calorie restriction, and offspring that underwent catch‐up growth became more obese than Cs. The HCD was associated with hyperphagia, hyperglycemia, hyperinsulinemia, glucose intolerance, insulin resistance, and adipocyte hypertrophy. The magnitude of effects varied depending on the type and the timing of early malnutrition. The expression of genes encoding factors implicated in cardiovascular disease was also modulated differently by early malnutrition and adult obesity.

Discussion: Catch‐up growth immediately after early malnutrition should be a key point for the programming of obesity.
Mesenteric Adipose Tissue‐Derived Monocyte Chemoattractant Protein‐1 Plays a Crucial Role in Adipose Tissue Macrophage Migration and Activation in Obese Mice
Authors: Yu Rina , Kim Chu‐Sook , Kwon Byung‐Se , Kawada Teruo
Published: April 2008

Objective: To determine whether chemokines, which play a pivotal role in monocyte/macrophage trafficking, modulate macrophage infiltration into and activation in the adipose tissues.

Research Methods and Procedures: Various types of adipose tissue were isolated from different fat depots (e.g., mesenteric, epididymal, renal, and subcutaneous adipose tissues) from obese mice fed a high‐fat diet and from non‐obese controls fed a standard diet. The isolated tissues were cultured for 24, 48, and 72 hours. The level of monocyte chemoattractant protein‐1 (MCP‐1) expression and the amount of protein released were measured by reverse transcriptase‐polymerase chain reaction or enzyme‐linked immunosorbent assay, respectively. Chemotaxis assay was performed to measure the degree of macrophage migration. Macrophage activation was estimated by measuring the concentrations of nitric oxide and tumor necrosis factor α.

Results: The level of MCP‐1 mRNA expression, protein content, and the amount of protein released significantly increased in the adipose tissues from the obese mice compared with those from the non‐obese mice. The mesenteric adipose tissue produced the highest levels of MCP‐1 protein among the four different fat depots. Mesenteric adipose tissue‐conditioned medium induced the highest degree of macrophage migration and strongly induced macrophages to produce proinflammatory mediators such as nitric oxide and tumor necrosis factor α. The neutralization of MCP‐1 in the adipose tissue‐conditioned medium significantly inhibited the migration and activation of macrophages.

Discussion: Our findings suggest that MCP‐1 plays a crucial role in adipose tissue inflammatory response by activating and inducing the infiltration of macrophages into adipose tissues. MCP‐1 may be closely associated with visceral obesity‐related complications and, thus, may be a useful therapeutic target for modulating visceral obesity‐related diseases.
Peripheral Mechanisms of Sibutramine Involving Proximal Gastric Motility in Dogs
Authors: Xu Junying , Chen Jiande D.Z.
Published: April 2008

Objective: Sibutramine, a serotonin‐norepinephrine uptake inhibitor, has been used for treating obesity. However, its possible mechanisms involving gastric motility have not been reported. The aim of this study was to evaluate the effects of sibutramine on gastric accommodation and antral motility.

Research Methods and Procedures: The study was performed in seven dogs with a stomach cannula and composed of two separate experiments: antral contractions and gastric tone. Each experiment included two sessions on 2 separate days in a randomized order: a control session and a treatment session with sibutramine (5 mg/kg per os) administrated 2 hours before the study.

Results: Sibutramine significantly increased fasting gastric tone; the gastric volume in the fasting state at baseline was 103.8 ± 12.3 mL and significantly decreased to 35.3 ± 16.0 mL with sibutramine (p = 0.0075). Sibutramine also impaired gastric accommodation. The average postprandial gastric volume was 472.1 ± 16.7 mL in the control session and reduced to 302.2 ± 53.6 mL with sibutramine (p = 0.013). The average postprandial increase in gastric volume during the 60‐minute postprandial period with sibutramine was significantly lower than the corresponding values in the control session: 266.8 ± 46.1 vs. 393.9 ± 15.3 mL (p = 0.03). Sibutramine had no effects on postprandial antral contractions.

Discussion: Sibutramine increases gastric tone and impairs gastric accommodation to an orally ingested meal. The inhibitory effect of sibutramine on gastric accommodation may partially explain the reduced food intake with sibutramine in patients with obesity.
Eating in the Absence of Hunger: A Genetic Marker for Childhood Obesity in Prepubertal Boys?
Authors: Faith Myles S. , Berkowitz Robert I. , Stallings Virginia A. , Kerns Julia , Storey Megan , Stunkard Albert J.
Published: April 2008

Objective: Eating in the absence of hunger (EAH) may be a behavioral trait through which obesity‐promoting genes promote positive energy balance. The primary aim of this study was to compare children born at high vs. low risk for obesity with respect to EAH at 5 years of age.

Research Methods and Procedures: This was an observational investigation of families enrolled in the University of Pennsylvania and The Children's Hospital of Philadelphia's Infant Growth Study. Five‐year‐old children born at high (N = 28) or low (N = 25) risk for obesity on the basis of maternal prepregnancy body weight were evaluated at a hospital‐based laboratory. Children consumed 11 snack foods ad libitum after consuming an ad libitum dinner and reporting fullness. Parents reported on snack foods at home and their own eating styles. Nutritive sucking at 3 months of age was evaluated by computerized apparatus.

Results: EAH in high‐risk boys (mean ± standard error = 326 ± 66 kJ] was more than twice that of low‐risk boys (mean ± standard error = 151 ± 39 kJ), p = 0.03. Among girls, there was a trend for EAH to be associated with increased parental limitations on daughter snack food consumption at home (p = 0.06). EAH was unrelated to 3‐month sucking behavior.

Discussion: Genes that promote childhood obesity may partially exert their influence through EAH, an effect that was limited to boys born at risk for obesity. The unique influences of genes and home environment on this trait should be disaggregated in subsequent studies.
Prospective Associations between Sedentary Lifestyle and BMI in Midlife
Authors: Mortensen Laust H. , Siegler Ilene C. , Barefoot John C. , Grønbæk Morten , Sørensen Thorkild I.A.
Published: April 2008

Objective: A strong positive cross‐sectional relationship between BMI and a sedentary lifestyle has been consistently observed in numerous studies. However, it has been questioned whether high BMI is a determinant or a consequence of a sedentary lifestyle.

Research Methods and Procedures: Using data from four follow‐ups of the University of North Carolina Alumni Heart Study, we examined the prospective associations between BMI and sedentary lifestyle in a cohort of 4595 middle‐aged men and women who had responded to questionnaires at the ages of 41 (standard deviation 2.3), 44 (2.3), 46 (2.0), and 54 (2.0).

Results: BMI was consistently related to increased risk of becoming sedentary in both men and women. The odds ratios of becoming sedentary as predicted by BMI were 1.04 (95% confidence limits, 1.00, 1.07) per 1 kg/m2 from ages 41 to 44, 1.10 (1.07, 1.14) from ages 44 to 46, and 1.12 (1.08, 1.17) from ages 46 to 54. Controlling for concurrent changes in BMI marginally attenuated the effects. Sedentary lifestyle did not predict changes in BMI, except when concurrent changes in physical activity were taken into account (p < 0.001). The findings were not confounded by preceding changes in BMI or physical activity, age, smoking habits, or sex.

Discussion: Our findings suggest that a high BMI is a determinant of a sedentary lifestyle but did not provide unambiguous evidence for an effect of sedentary lifestyle on weight gain.
Effects of Resistant Starch, A Non‐digestible Fermentable Fiber, on Reducing Body Fat
Authors: Keenan Michael J. , Zhou Jun , McCutcheon Kathleen L. , Raggio Anne M. , Bateman H. Gale , Todd Emily , Jones Christina K. , Tulley Richard T. , Melton Sheri , Martin Roy J. , Hegsted Maren
Published: April 2008

Objective: To assess the effects of energy dilution with non‐fermentable and fermentable fibers on abdominal fat and gut peptide YY (PYY) and glucagon‐like peptide (GLP)‐1 expressions, three rat studies were conducted to: determine the effects of energy dilution with a non‐fermentable fiber, compare similar fiber levels of fermentable and non‐fermentable fibers, and compare similar metabolizable energy dilutions with fermentable and non‐fermentable fibers.

Research Methods and Procedures: In Study 1, rats were fed one of three diets with different metabolizable energy densities. In Study 2, rats were fed diets with similar fiber levels using high amylose‐resistant cornstarch (RS) or methylcellulose. In Study 3, rats were fed diets with a similar dilution of metabolizable energy using cellulose or RS. Measurements included food intake, body weight, abdominal fat, plasma PYY and GLP‐1, gastrointestinal tract weights, and gene transcription of PYY and proglucagon.

Results: Energy dilution resulted in decreased abdominal fat in all studies. In Study 2, rats fed fermentable RS had increased cecal weights and plasma PYY and GLP‐1, and increased gene transcription of PYY and proglucagon. In Study 3, RS‐fed rats had increased short‐chain fatty acids in cecal contents, plasma PYY (GLP‐1 not measured), and gene transcription for PYY and proglucagon.

Discussion: Inclusion of RS in the diet may affect energy balance through its effect as a fiber or a stimulator of PYY and GLP‐1 expression. Increasing gut hormone signaling with a bioactive functional food such as RS may be an effective natural approach to the treatment of obesity.
Physiological Evidence for the Involvement of Peptide YY in the Regulation of Energy Homeostasis in Humans
Authors: Guo Yan , Ma Lijun , Enriori Pablo J. , Koska Juraj , Franks Paul W. , Brookshire Thomas , Cowley Michael A. , Salbe Arline D. , DelParigi Angelo , Tataranni P. Antonio
Published: April 2008

Objective: To explore the potential role of the endogenous peptide YY (PYY) in the long‐term regulation of body weight and energy homeostasis.

Research Methods and Procedures: Fasting and postprandial plasma PYY concentrations were measured after an overnight fast and 30 to 180 minutes after a standardized meal in 29 (21 men/8 women) non‐diabetic subjects, 16 of whom had a follow‐up visit 10.8 ± 1.4 months later. Ratings of hunger and satiety were collected using visual analog scales. Resting metabolic rate (RMR) (15‐hour RMR) and respiratory quotient (RQ) were assessed using a respiratory chamber.

Results: Fasting PYY concentrations were negatively correlated with various markers of adiposity and negatively associated with 15‐hour RMR (r = −0.46, p = 0.01). Postprandial changes in PYY (area under the curve) were positively associated with postprandial changes in ratings of satiety (r = 0.47, p = 0.01). The maximal PYY concentrations achieved after the meal (peak PYY) were negatively associated with 24‐hour RQ (r = −0.41, p = 0.03). Prospectively, the peak PYY concentrations were negatively associated with changes in body weight (r = −0.58, p = 0.01).

Discussion: Our data indicate that the endogenous PYY may be involved in the long‐term regulation of body weight. It seems that this long‐term effect was not exclusively driven by the modulation of food intake but also by the control of energy expenditure and lipid metabolism.
Long‐Term Effects of Obesity on Employment and Work Limitations Among U.S. Adults, 1986 to 1999
Authors: Tunceli Kaan , Li Kemeng , Williams L. Keoki
Published: April 2008

Objective: To determine the relationships between BMI and workforce participation and the presence of work limitations in a U.S. working‐age population.

Research Methods and Procedures: We used data from the Panel Study of Income Dynamics, a nationwide prospective cohort, to estimate the effect of obesity in 1986 on employment and work limitations in 1999. Individuals were classified into the following weight categories: underweight (BMI < 18.5), normal weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30). Using multivariable probit models, we estimated the relationships between obesity and both employment and work disability. All analyses were stratified by sex.

Results: After adjusting for baseline sociodemographic characteristics, smoking status, exercise, and self‐reported health, obesity was associated with reduced employment at follow‐up [men: marginal effect (ME) −4.8 percentage points (pp); p < 0.05; women: ME −5.8 pp; p < 0.10]. Among employed women, being either overweight or obese was associated with an increase in self‐reported work limitations when compared with normal‐weight individuals (overweight: ME +3.9 pp; p < 0.01; obese: ME +12.6 pp; p < 0.01). Among men, the relationship between obesity and work limitations was not statistically significant.

Discussion: Obesity appears to result in future productivity losses through reduced workforce participation and increased work limitations. These findings have important implications in the U.S., which is currently experiencing a rise in the prevalence of obesity.
Racial Differences in Correlates of Misreporting of Energy Intake in Adolescent Females
Authors: Kimm Sue Y.S. , Glynn Nancy W. , Obarzanek Eva , Aston Christopher E. , Daniels Stephen R.
Published: April 2008

Objective: To determine the extent of misreporting of energy intake (EI) and its anthropometric, demographic, and psychosocial correlates in a bi‐racial cohort of young women.

Research Methods and Procedures: This was a cross‐sectional study of 60 black and 60 white young women, 18 to 21 years old, enrolled in a longitudinal study. Total energy expenditure was assessed using doubly labeled water. Self‐reported EI was obtained from 3‐day food records. BMI was computed from height and weight. Fat mass was assessed by DXA. Multivariate analyses examined racial differences on the extent of misreporting and its effect on other potential correlates of misreporting. Race‐specific step‐wise linear regression analysis was performed to examine the effect of BMI, parental education, and drive for thinness on misreporting of EI.

Results: More white women tended to under‐report EI than black women (22% vs. 13%, p = 0.07). In black women, under‐reporting was significantly (p = 0.01) associated with drive for thinness score but was only marginally (p = 0.1) associated with BMI. Each point increase in drive for thinness score was associated with under‐reporting by 40 kcal/d. In white women, under‐reporting was significantly (p = 0.03) associated with higher parental education by 440 kcal/d and also only marginally (p = 0.09) with BMI.

Discussion: This tendency for under‐reporting of EI limits the use of self‐reported EI in studying energy balance in free‐living subjects. Most black and almost all white women in their late teens significantly under‐reported their EI, whereas under‐reporting was not as evident among lean young black women.
The Effects of Increasing Serum Calcitriol on Energy and Fat Metabolism and Gene Expression
Authors: Boon Niels , Hul Gabby B. J. , Sicard Audrey , Kole Eveline , Van, Den Berg Elisa R. , Viguerie Nathalie , Langin Dominique , Saris Wim H. M.
Published: April 2008

Objective: Evidence from a number of investigations indicates that calcium intake could be inversely related to body weight through alterations in the 1,25‐OH2‐D3 metabolism. The objective of this study was to test whether energy and substrate metabolism and adipose tissue enzyme mRNA expression can be altered by changes in serum 1,25‐OH2‐D3 through oral cholecalciferol supplementation in non‐obese human subjects.

Research Methods and Procedures: An intervention study was used with a treatment period of 7 days. During this intervention, energy expenditure (EE) and substrate metabolism were measured using indirect calorimetry at t = 0, 1, 3, and 7 days, and blood samples were obtained at t = −1, 0, 1, 2, 3, 5 and 7 days. Fat biopsies were obtained at t = 0 and 7 days for determination of expression of genes involved in lipolytic and lipogenic pathways. Subjects from the general community were studied in an ambulatory setting at a university hospital. Ten healthy young men (age, 28 ± 3 years; BMI, 25.5 ± 0.5 kg/m2) were recruited by local announcement, and all completed the study. All subjects received 2000 IU cholecalciferol/d for 7 days, and they were instructed to consume a low‐cholecalciferol, low‐calcium diet. EE, fat oxidation, and adipose tissue enzyme mRNA were the main outcome measures.

Results: Despite a significant increase in serum 1,25‐OH2‐D3 concentration at t = 5 and 7 days, no significant differences in substrate and energy metabolism nor mRNA concentrations of different lipid metabolism‐related proteins were observed.

Discussion: Seven‐day supplementation with 2000 IU cholecalciferol/d together with a decrease in dietary calcium intake does not affect EE or substrate metabolism nor gene expression of proteins related to fat metabolism, despite a significant increase in serum 1,25‐OH2‐D3 concentration.
Body Composition and Breast Cancer in Postmenopausal Women: A Danish Prospective Cohort Study
Authors: Mellemkjær Lene , Bigaard Janne , Tjønneland Anne , Christensen Jane , Thomsen Birthe , Johansen Christoffer , Overvad Kim , Olsen Jørgen H.
Published: April 2008

Objective: To assess the importance of body fat mass (BFM) and fat free mass (FFM) for the established positive association between BMI and breast cancer among post‐menopausal women.

Research Methods and Procedures: A prospective cohort of 23,788 postmenopausal women included in the Danish study Diet, Cancer, and Health during 1993 to 1997 was linked to the Danish Cancer Registry to identify all cases of breast cancer occurring during 1993 to 2002. Breast cancer incidence rate ratios for anthropometric measurements with adjustment for known risk factors for breast cancer were calculated by Cox regression analyses.

Results: Among the most commonly used anthropometric measurements, BMI was positively associated with breast cancer among never users of hormone replacement therapy (HRT). By splitting BMI into two indices, BFM index and FFM index, we found that the incidence rate ratio with each 1 kg/m2 among never users of HRT was 0.98 (95% confidence interval, 0.93 to 1.03) for BFM index and 1.12 (95% confidence interval, 1.00 to 1.26) for FFM index after mutual adjustment.

Discussion: The finding for BMI was in accordance with previous findings. Our results indicate that the FFM component of BMI may play a role for development of breast cancer among never users of HRT.
ABCA1 Single Nucleotide Polymorphisms on High‐Density Lipoprotein‐Cholesterol and Overweight: the D.E.S.I.R. Study
Authors: Porchay Isabelle , Péan Franck , Bellili Naïma , Royer Bernard , Cogneau Joël , Chesnier Marie‐Claude , Caradec Ariane , Tichet Jean , Balkau Beverley , Marre Michel , Fumeron Frédéric
Published: April 2008

The adenosine triphosphate‐binding cassette A1 (ABCA1) gene plays a key role in reverse cholesterol transport. Some ABCA1 gene polymorphisms have been associated with high‐density lipoprotein‐cholesterol (HDL‐C) concentrations. The aim of this study was to assess the effect of three polymorphisms, C69T, G378C, and G1051A (R219K), on HDL‐C levels and their interaction with BMI in more than 5000 French whites from the D.E.S.I.R. (Data from an Epidemiological Study on the Insulin Resistance syndrome) cohort study. The T allele of the C69T single nucleotide polymorphism (SNP) was associated with higher HDL‐C levels in normal‐weight men (BMI <25 kg/m2). The C allele of the G378C SNP was associated with lower HDL‐C in overweight subjects (BMI ≥25 kg/m2). For the G1051A SNP, in the normal‐weight group, the minor A allele was significantly associated with higher HDL‐C levels. In contrast, in overweight people, the minor allele was associated with lower HDL‐C levels. After accounting for multiple testing, empiric p values remained significant for the associations between G378C SNP and HDL‐C in the overweight group and between G1051A SNP and HDL‐C in the normal‐weight group. This study suggests that ABCA1 gene polymorphisms modulate HDL‐C concentrations, in interaction with BMI, and, thus, they might influence cardiovascular risk in the general population.
Serum Phospholipid Fatty Acids, Adipose Tissue, and Metabolic Markers in Obese Adolescents
Authors: Karlsson Martin , Mårild Staffan , Brandberg John , Lönn Lars , Friberg Peter , Strandvik Birgitta
Published: April 2008

Objective: Fatty acid (FA) composition has a role in adipogenesis. The objective was to study serum phospholipid (PL) FAs in adolescents and their relation to abdominal adipose tissue (AT) compartments and metabolic markers.

Research Methods and Procedures: Abdominal AT was measured by magnetic resonance imaging and FA pattern was determined in serum PL of 10 obese adolescents (5 females), median age 12.0 years (range, 10.4 to 16.4) and BMI 30.7 (26.8 to 40.4), and 15 lean control subjects (9 females), median age 12.6 years (range, 11.3 to 15.4), and BMI 19.5 (17.1 to 23.4).

Results: Obese adolescents had relatively higher levels of saturated FA (SFA) and nervonic acid compared with controls. Serum PL concentration of n‐3 polyunsaturated fatty acids (PUFA) was lower in the obese vs. lean females (p = 0.01), including docosahexaenoic acid (DHA) (p = 0.01). The ratios of arachidonic acid to DHA and total n‐6/n‐3 FA were increased in obese children (p = 0.02 and 0.01, respectively). n‐3 PUFAs were inversely correlated to all subcutaneous AT compartments except visceral AT. The homeostasis model assessment index of β‐cell function related inversely to DHA concentration (p = 0.03). All changes were more marked in the females.

Discussion: Serum FA pattern in obese adolescents differed significantly from that in age‐matched lean controls, reflecting a decrease in n‐3 PUFA, especially DHA, and an increase in SFA. The subcutaneous AT, but not visceral AT, correlated to the changes in PUFA and SFA, suggesting an abnormal essential FA metabolism in obese adolescents.
True Fractional Calcium Absorption is Decreased After Roux‐En‐Y Gastric Bypass Surgery
Authors: Riedt Claudia S. , Brolin Robert E. , Sherrell Robert M. , Field M. Paul , Shapses Sue A.
Published: April 2008

Objective: Roux‐en‐Y gastric bypass (RYGB) is considered to be the gold standard alternative treatment for severe obesity. Weight loss after RYGB results primarily from decreased food intake. Inadequate calcium (Ca) intake and metabolic bone disease can occur after gastric bypass. To our knowledge, whether malabsorption of Ca contributes to an altered Ca metabolism in the RYGB patient has not been addressed previously.

Research Methods and Procedures: We recruited 25 extremely obese women in order to study true fractional Ca absorption (TFCA) before and 6 months after RYGB surgery, using a dual stable isotope method (42Ca and 43Ca) and test load of Ca (200 mg). Hormones regulating Ca absorption and markers of bone turnover were also measured.

Results: In 21 women (BMI 52.7 ± 8.3 kg/m2, age 43.9 ± 10.4 years) who successfully completed the study, TFCA decreased from 0.36 ± 0.08 to 0.24 ± 0.09 (p < 0.001) after RYGB. Bone turnover markers increased significantly (p < 0.01). TFCA correlated with estradiol levels (r = 0.512, p < 0.02) and tended to correlate with 1,25 (OH)2D (r = 0.427, p < 0.06) at final measurement. Stepwise linear regression indicated that estradiol explained 62% of the variance for TFCA at 6 months post‐surgery (p < 0.01).

Discussion: TFCA decreases (0.12 ± 0.08) after RYGB surgery but remains within normal range. Although only some patients were estimated to have low Ca absorption after surgery, all of the patients showed a dramatic increase in markers of bone resorption. The alteration in Ca metabolism after RYGB‐induced weight loss appears to be regulated primarily by estradiol levels and might ultimately affect bone mass.
Categorization of Low Cardiorespiratory Fitness Using Obesity Indices in Non‐smoking Singaporean Women
Authors: Pua Yong‐Hao , Lim Cheng‐Kuan , Ang Adele
Published: April 2008

Objective: To revisit cut‐off values of BMI, waist circumference (WC), and waist‐to‐stature ratio (WSR) based on their association with cardiorespiratory fitness (CRF). The derived cut‐off points were compared with current values (BMI, 25.0 kg/m2; WC, 80 cm) as recommended by the World Health Organization.

Research Methods and Procedures: Anthropometric indices were measured in a cross sectional study of 358 Singaporean female employees of a large tertiary hospital (63% Singaporean Chinese, 28% Malays, and 9% Indians). CRF was determined by the 1‐mile walk test. Receiver operating characteristic curves were constructed to determine cut‐off points.

Results: The cut‐off points for BMI, WC, and WSR were 23.6 kg/m2, 75.3 cm, and 0.48, respectively. The areas under the curve of BMI, WC, and WSR were 0.68, 0.74, and 0.74, respectively. For a given BMI, women with low CRF had higher WSR compared with women with high CRF.

Discussion: These findings provide convergent evidence that the cut‐off points for Singaporean women were lower than the World Health Organization's criteria but were in good agreement with those reported for Asians.
A Randomized Clinical Trial Testing Treatment Preference and Two Dietary Options in Behavioral Weight Management: Preliminary Results of the Impact of Diet at 6 Months—PREFER Study
Authors: Burke Lora E. , Styn Mindi A. , Steenkiste Ann R. , Music Edvin , Warziski Melanie , Choo Jina
Published: April 2008

Objective: The PREFER study objectives were to examine potential differences in weight loss during a standard behavioral intervention between subjects assigned to one of two calorie‐ and fat‐restricted diets [standard behavior treatment (SBT) and lacto‐ovo‐vegetarian ([SBT+LOV)], with or without regard to their preferred dietary treatment. This article reports the differences in outcomes between diet groups after the first 6 months of the intervention.

Research Methods and Procedures: The study used a four‐group design. Subjects (n = 182) were randomized to a treatment preference group and then to a dietary treatment group. For this report, preference groups were combined to permit comparisons by dietary treatment only (SBT, n = 98; SBT+LOV, n = 84). Additional analyses compared SBT+LOV subjects who were 100% adherent (did not consume any meat, fish, or poultry, n = 47) to those who were <100% adherent (n = 24).

Results: Significant differences were seen in the baseline to 6‐month change scores between the two groups for carbohydrate consumption (p = 0.013), protein consumption (p < 0.001), polyunsaturated‐to‐saturated fat ratio (p = 0.009), and low‐density lipoprotein‐cholesterol (LDL‐C) level (p = 0.013). Among SBT+LOV subjects, those who were 100% adherent experienced greater reductions in weight (p < 0.001), total cholesterol (p = 0.026), LDL‐C (p = 0.034), and glucose (p = 0.002) and consumed less fat (p = 0.030) compared with those who were <100% adherent.

Discussion: Differences between dietary treatment groups at 6 months were minimal, most likely because one‐third of the SBT+LOV group did not follow the vegetarian diet and because both groups had the same calorie and fat restrictions. SBT+LOV subjects who were 100% adherent were more successful at both weight loss and cholesterol reduction than those who were <100% adherent, suggesting that vegetarian diets are efficacious for weight and cholesterol control.
Maternal Feeding Strategies, Child Eating Behaviors, and Child BMI in Low‐Income African‐American Preschoolers
Authors: Powers Scott W. , Chamberlin Leigh A. , van Schaick Kelly B. , Sherman Susan N. , Whitaker Robert C.
Published: April 2008

Objective: To test the hypothesis that low‐income African‐American preschool children would have a higher BMI if their mothers reported greater “restriction” and “control” in feeding and if mothers reported that children showed greater “food responsiveness” and “desire to drink.” In addition, to test whether higher maternal “pressure to eat” would be associated with lower child BMI.

Research Methods and Procedures: A questionnaire was completed by 296 low‐income African‐American mothers of preschool children. It assessed three constructs on maternal feeding strategies (“restriction,” “pressure to eat,” and “control”) and two on child eating behaviors (“food responsiveness” and “desire to drink”). Children's BMI was measured, and mothers’ BMI was self‐reported.

Results: The mean (standard deviation) BMI z‐score of the children was 0.34 (1.5), and 44% of the mothers were obese (BMI ≥30 kg/m2). Only maternal “pressure to eat” had a significant overall association with child BMI z‐score (r = −0.16, p < 0.01). Both maternal “restriction” and “control” were positively associated with children's BMI z‐score in the case of obese mothers (r = 0.20, p = 0.03 and r = 0.24, p = 0.007, respectively), but this was not so in the case of non‐obese mothers (r = −0.16, p = 0.05 and r = −0.07, p = 0.39, respectively).

Discussion: Among low‐income African Americans, the positive association between maternal restriction and control in feeding and their preschoolers’ BMI was limited to obese mothers. Relations between parent feeding strategies and child weight status in this population may differ on the basis of maternal weight status.
Peptide YY Levels Are Elevated After Gastric Bypass Surgery
Authors: Chan Jean L. , Mun Edward C. , Stoyneva Violeta , Mantzoros Christos S. , Goldfine Allison B.
Published: April 2008

Objective: Mechanisms that promote effective and sustained weight loss in persons who have undergone Roux‐en‐Y gastric bypass surgery are incompletely understood but may be mediated, in part, by changes in appetite. Peptide YY (PYY) is a gut‐derived hormone with anorectic properties. We sought to determine whether gastric bypass surgery alters PYY levels or response to glucose.

Research Methods and Procedures: PYY and ghrelin levels after a 75‐gram oral glucose tolerance test were measured in 6 morbidly obese patients 1.5 ± 0.7 (SE) years after gastric bypass compared with 5 lean and 12 obese controls.

Results: After substantial body weight loss (36.8 ± 3.6%) induced by gastric bypass, the PYY response to an oral glucose tolerance test was significantly higher than in controls (p = 0.01). PYY increased ∼10‐fold after a 75‐gram glucose load to a peak of 303.0 ± 37.0 pg/mL at 30 minutes (p = 0.03) and remained significantly higher than fasting levels for all subsequent time‐points. In contrast, PYY levels in obese and lean controls increased to a peak of ∼2‐fold, which was only borderline significant. Ghrelin levels decreased in a symmetric but opposite fashion to that of PYY.

Discussion: Gastric bypass results in a more robust PYY response to caloric intake, which, in conjunction with decreased ghrelin levels, may contribute to the sustained efficacy of this procedure. The findings provide further evidence for a role of gut‐derived hormones in mediating appetite changes after gastric bypass and support further efforts to determine whether PYY3–36 replacement could represent an effective therapy for obesity.