Health Effects of Overweight and Obesity in 195 Countries over 25 Years

Physical performance measures in screening for reduced lean body mass in adult females with obesity

BACKGROUND & AIMS

Little is known about the reduction of lean body mass (LBM) in obesity, or how to identify it in standard clinical settings. We therefore aimed to assess the prevalence of low LBM in adult females with obesity, and to identify the reliability of simple tools for its screening in this population.

METHODS AND RESULTS

Dual-energy X-ray absorptiometry (DXA) body composition assessment was used to categorise 147 female participants with obesity as with or without low LBM, according to the new definition that takes into account both appendicular lean mass (ALM) and body mass index (BMI)-ALM/BMI <0.512. Participants were also administered the six-minute walking test, handgrip-strength test and 4-metre gait-speed test. Of the sample of 147 participants, 93 (63.3%) met the criteria for reduced LBM. Stepwise multivariate logistic regression analysis showed that the six-minute walking test was the only independent test associated with low LBM (OR = 0.992, 95%CI 0.987-0.998). Receiver operating characteristic (ROC) curve analysis found that the discriminating cut-off points of the tests considered were 470 m, 3.30 s (gait speed = 1.2 m/sec) and 23.5 kg respectively; the 4-metre gait-speed test seems to provide the best balance of sensitivity and specificity, and the greatest discriminatory power at 90% sensitivity.

CONCLUSIONS

Treatment-seeking adult females with obesity display a great prevalence of reduced LBM. The six-minute walking test was the only independent test associated with low LBM, but the 4-metre gait-speed test seems to be the most accurate functional test for screening for this condition in that population.

Metabolomic analysis of obesity, metabolic syndrome, and type 2 diabetes: amino acid and acylcarnitine levels change along a spectrum of metabolic wellness

Background

Metabolic syndrome (MS) is a construct used to separate “healthy” from “unhealthy” obese patients, and is a major risk factor for type 2 diabetes (T2D) and cardiovascular disease. There is controversy over whether obese “metabolically well” persons have a higher morbidity and mortality than lean counterparts, suggesting that MS criteria do not completely describe physiologic risk factors or consequences of obesity. We hypothesized that metabolomic analysis of plasma would distinguish obese individuals with and without MS and T2D along a spectrum of obesity-associated metabolic derangements, supporting metabolomic analysis as a tool for a more detailed assessment of metabolic wellness than currently used MS criteria.

Methods

Fasting plasma samples from 90 adults were assigned to groups based on BMI and ATP III criteria for MS: (1) lean metabolically well (LMW; n = 24); (2) obese metabolically well (OBMW; n = 26); (3) obese metabolically unwell (OBMUW; n = 20); and (4) obese metabolically unwell with T2D (OBDM; n = 20). Forty-one amino acids/dipeptides, 33 acylcarnitines and 21 ratios were measured. Obesity and T2D effects were analyzed by Wilcoxon rank-sum tests comparing obese nondiabetics vs LMW, and OBDM vs nondiabetics, respectively. Metabolic unwellness was analyzed by Jonckheere-Terpstra trend tests, assuming worsening health from LMW → OBMW → OBMUW. To adjust for multiple comparisons, statistical significance was set at p < 0.005. K-means cluster analysis of aggregated amino acid and acylcarnitine data was also performed.

Results

Analytes and ratios significantly increasing in obesity, T2D, and with worsening health include: branched-chain amino acids (BCAAs), cystine, alpha-aminoadipic acid, phenylalanine, leucine + lysine, and short-chain acylcarnitines/total carnitines. Tyrosine, alanine and propionylcarnitine increase with obesity and metabolic unwellness. Asparagine and the tryptophan/large neutral amino acid ratio decrease with T2D and metabolic unwellness. Malonylcarnitine decreases in obesity and 3-OHbutyrylcarnitine increases in T2D; neither correlates with unwellness. Cluster analysis did not separate subjects into discreet groups based on metabolic wellness.

Discussion

Levels of 15 species and metabolite ratios trend significantly with worsening metabolic health; some are newly recognized. BCAAs, aromatic amino acids, lysine, and its metabolite, alpha-aminoadipate, increase with worsening health. The lysine pathway is distinct from BCAA metabolism, indicating that biochemical derangements associated with MS involve pathways besides those affected by BCAAs. Even those considered “obese, metabolically well” had metabolite levels which significantly trended towards those found in obese diabetics. Overall, this analysis yields a more granular view of metabolic wellness than the sole use of cardiometabolic MS parameters. This, in turn, suggests the possible utility of plasma metabolomic analysis for research and public health applications.

Prospective cohort study of overweight and obesity among rural Indian adults: sociodemographic predictors of prevalence, incidence and remission

OBJECTIVES

To assess sociodemographic predictors of prevalence, incidence and remission of overweight including obesity among adults (aged ≥18 years) in rural Eastern India.

DESIGN

Prospective cohort study.

SETTING

Birbhum Health and Demographic Surveillance System, West Bengal, India.

PARTICIPANTS

Self-weighted sample of 24 115 adults (men: 10915, women: 13200) enrolled in 2008 were followed up for body mass index (BMI) reassessment in 2017.

PRIMARY AND SECONDARY OUTCOME MEASURES

Measured BMI was categorised as: underweight (<18.5 kg/m²), normal weight (18.5-22.9 kg/m²) and overweight including obesity (≥23 kg/m²; hereinafter overweight). Incident overweight was defined as transition from normal weight in 2008 to overweight in 2017, whereas if overweight individuals in 2008 measured normal BMI in 2017, it was classified as remission from overweight.

RESULTS

In 2008, 10.1% of men and 14.6% of women were overweight, whereas 17.3% of men and 24.7% of women were overweight in 2017. At the same time, in 2017, 35.6% of men and 33.3% of women were underweight. Incident overweight was 19.0% among men and 27.2% among women, whereas remission among men was higher (15.4%) than women (11.5%). Women were more likely to be overweight in 2008 and to experience incident overweight than men. For men and women, education level and wealth were positively associated with prevalence and incidence of overweight. Remission from overweight was less likely in Sainthia, a business hub in the district, as compared with Mohammad Bazar, a more rural area.

CONCLUSION

A nutrition transition to higher risk of overweight is evident in this rural setting in India, especially among women and individuals with high socioeconomic status. At the same time, a high prevalence of underweight persists, resulting in a significant double burden. Culturally sensitive interventions that address both ends of the malnutrition spectrum should be prioritised.

Regulation of Energy Expenditure and Brown/Beige Thermogenic Activity by Interleukins: New Roles for Old Actors

Obesity rates and the burden of metabolic associated diseases are escalating worldwide Energy burning brown and inducible beige adipocytes in human adipose tissues (ATs) have attracted considerable attention due to their therapeutic potential to counteract the deleterious metabolic effects of nutritional overload and overweight. Recent research has highlighted the relevance of resident and recruited ATs immune cell populations and their signalling mediators, cytokines, as modulators of the thermogenic activity of brown and beige ATs. In this review, we first provide an overview of the developmental, cellular and functional heterogeneity of the AT organ, as well as reported molecular switches of its heat-producing machinery. We also discuss the key contribution of various interleukins signalling pathways to energy and metabolic homeostasis and their roles in the biogenesis and function of brown and beige adipocytes. Besides local actions, attention is also drawn to their influence in the central nervous system (CNS) networks governing energy expenditure.

The paediatric option for BodPod to assess body composition in preschool children: what fat-free mass density values should be used?

Air displacement plethysmography utilises a two-component model to assess body composition, which relies on assumptions regarding the density of fat-free mass (FFM). To date, there is no evidence as to whether Lohman's or Wells et al.'s FFM density values are more accurate in young children. Therefore, the aims of this study were to compare total body fat percentage (TBF%) assessed using the BodPod with both Lohman's and Wells et al.'s FFM density values with TBF% from the three-component (3C) model in forty healthy Swedish children aged 5·5 years. Average TBF% calculated using Lohman's FFM density values underestimated TBF% in comparison with the corresponding value assessed using the 3C model (22·2 (sd 5·7) and 25·1 (sd 5·5) %, respectively; P<0·001). No statistically significant difference was observed between TBF% assessed using Wells et al.'s FFM density values and the 3C model (24·9 (sd 5·5) and 25·1 (sd 5·5) %, respectively; P=0·614). The Bland and Altman plots for TBF% using both Lohman's and Wells et al.'s FFM density values did not show any bias across the range of body fatness (Lohman: r 0·056, P=0·733 and Wells et al.: r -0·006, P=0·970). These results indicate that Wells et al.'s FFM density values should be used when assessing body composition with the paediatric option for BodPod in 5-year-old children. However, future studies are needed to confirm these results in other populations, including a wider age range of children.

Risk and Protective Factors for Child Overweight/Obesity Among Low Socio-Economic Populations in Israel: A Cross Sectional Study

Background and Aims: Scientific evidence regarding protective factors that contribute to healthy weight in childhood is limited and is particularly scarce in lower socio-economic populations in different ethnic groups. This study aimed to assess the prevalence of biological, behavioral and psychosocial factors for child overweight/obesity in Jewish and Arab population groups in Israel, and to compare their associations with child overweight/obesity in the two groups. Methods: Children aged 5-6 years were randomly selected from 20 Mother and Child Health clinics in towns and villages of lowest socio-economic ranking in Northern Israel. Children and mothers were invited for a special "One Stop Shop-Preparation for School" visit which included growth measurements. Questionnaires were distributed to mothers for self-report on biological, SES, psychological and lifestyle factors. Perinatal and early nutritional data were retrieved from clinic records. Multivariate analyses using logistic regression models predicting child overweight/obesity were conducted separately for Jewish (N = 371) and Arab (N = 575) children. Results: Overweight/obesity (BMI ≥85th centile) rates were higher in Jewish (25%) than Arab (19%) children. In both Jewish and Arab groups, respectively, maternal BMI (OR = 1.10 [95%CI = 1.04, 1.17]; OR = 1.08 [95%CI = 1.04, 1.13]), and child birthweight (OR = 1.33 [95%CI = 1.04, 1.71]; OR = 1.39 [95%CI = 1.11, 1.73]) were significant risk factors for overweight/obesity, and maternal self-efficacy regarding child's lifestyle was significantly protective (OR = 0.49 [95%CI = 0.28, 0.85]; OR = 0.54 [95%CI = 0.34, 0.85]). Additionally, four other maternal psychological and child behaviors were significantly associated with overweight/obesity in the Jewish group and two child lifestyle behavior factors in the Arab group. Moreover, significant interactions indicating moderation effects were found only in the Jewish group: maternal education and maternal age moderated the effect of maternal BMI on child overweight/obesity. No other moderation of risk factors was found. Discussion: In this study of children from low SES families, protective factors contributed to healthy child weight alongside risk factors for overweight/obesity. They differed between the population groups, and fewer variables explained overweight/obesity in Arab children. Although further expansion of these findings is required they point at the relevance of protective factors, maternal self-efficacy in particular, for understanding childhood obesity in specific ethnic contexts and for planning culturally adapted prevention programs in disadvantaged populations.

Antenatal anaesthesia clinics - the way forward?

Specialist antenatal clinics are increasingly being used to enable anaesthetists to evaluate pregnant women with co-morbidities and those at high risk of obstetric complications. In this journal a team from Israel describe the process of setting up and running such a clinic over a 14 year period. One of the challenges they identify was the limited referral of high risk women. Based on UK and US literature, the use of structured referral tools, clear criteria for referral and regular antenatal multidisciplinary meetings may help to address this.

Genetics of Severe Obesity

PURPOSE OF REVIEW

This review aims to present current information on genes underlying severe obesity, with the main emphasis on the three genes LEP, LEPR and MC4R.

RECENT FINDINGS

There is a substantial amount of evidence that variants in at least ten different genes are the cause of severe monogenic obesity. The majority of these are involved in the leptin-melanocortin signalling pathway. Due to the frequency of some of the identified variants, it is clear that monogenic variants also make a significant contribution to common obesity. The artificial distinction between rare monogenic obesity and common polygenic obesity is now obsolete with the identification of MC4R variants of strong effect in the general population.

How and why weight stigma drives the obesity 'epidemic' and harms health

BACKGROUND

In an era when obesity prevalence is high throughout much of the world, there is a correspondingly pervasive and strong culture of weight stigma. For example, representative studies show that some forms of weight discrimination are more prevalent even than discrimination based on race or ethnicity.

DISCUSSION

In this Opinion article, we review compelling evidence that weight stigma is harmful to health, over and above objective body mass index. Weight stigma is prospectively related to heightened mortality and other chronic diseases and conditions. Most ironically, it actually begets heightened risk of obesity through multiple obesogenic pathways. Weight stigma is particularly prevalent and detrimental in healthcare settings, with documented high levels of 'anti-fat' bias in healthcare providers, patients with obesity receiving poorer care and having worse outcomes, and medical students with obesity reporting high levels of alcohol and substance use to cope with internalized weight stigma. In terms of solutions, the most effective and ethical approaches should be aimed at changing the behaviors and attitudes of those who stigmatize, rather than towards the targets of weight stigma. Medical training must address weight bias, training healthcare professionals about how it is perpetuated and on its potentially harmful effects on their patients.

CONCLUSION

Weight stigma is likely to drive weight gain and poor health and thus should be eradicated. This effort can begin by training compassionate and knowledgeable healthcare providers who will deliver better care and ultimately lessen the negative effects of weight stigma.

Interaction between Parental Education and Household Wealth on Children's Obesity Risk

Parents’ education and household wealth cannot be presumed to operate independently of each other. However, in traditional studies on the impact of social inequality on obesity, education and financial wealth tend to be viewed as separable processes. The present study examines the interaction of parents’ education and household wealth in relation to childhood obesity. Anthropometric measurement and questionnaire surveys were carried out on 3670 children (aged 9–12 years) and their parents from 26 elementary schools in northeast China. Results showed that the interaction term was significant for household wealth and father’s education (p < 0.01), while no significant interaction between household wealth and mother’s education was found. In a separate analysis, the interaction was statistically significant among girls for obesity risk based on BMI (p = 0.02), and among urban children for both obesity risk based on BMI (p = 0.01) and abdominal obesity risk based on WHR (p = 0.03). Specifically, when household wealth increased from the first quintile to the fifth quintile, OR for father’s education decreased from higher than 1 (OR = 1.95; 95% CI: 1.12–3.38) to non-significant for girl’s obesity risk, from non-significant to lower than 1 for urban children’s obesity risk (OR = 0.52; 95% CI: 0.32–0.86 for the fourth quintile; OR = 0.37; 95% CI: 0.19–0.73 for the fifth quintile) and from higher than 1 (OR = 1.61; 95% CI: 1.04–2.05) to non-significant for urban children’s abdominal obesity risk. These findings indicate that father’s education level interacts with household wealth to influence obesity among girls and urban children in northeast China.

Sugar and energy content of carbonated sugar-sweetened beverages in Haidian District, Beijing: a cross-sectional study

OBJECTIVE

The consumption of carbonated sugar-sweetened beverages (CSSBs) is associated with a range of health problems, but little is known about the sugar and energy content of CSSBs in China. The study aimed to investigate the sugar and energy content of CSSBs in Beijing, China.

STUDY DESIGN

We carried out a cross-sectional survey in 15 different supermarkets from July to October 2017 in Haidian District, Beijing.

METHODS

The product packaging and nutrient labels of CSSBs were recorded by a snapshot in time to obtain company name, product name, serving size, and nutrient content, that is, carbohydrate, sugar and energy. For CSSB labels not showing sugar content, we used carbohydrate content as substitute. The sugar and energy content of CSSBs within each type of flavour were compared using Kruskal-Wallis test. The sugar content within the recommended levels was described using frequency. We also compared the sugar and energy content of top 5 CSSBs in terms of sales among three countries (China, UK and USA).

RESULTS

A total of 93 CSSB products were found. The median sugar content was 9.3 (IQR: 5.7-11.2) g/100 mL, and the energy content was 38 (IQR: 23-46) kcal/100 mL. There were 79 products labelled 'Red' (high) per serving based on the criteria set in the UK (>11.25 g/100 mL). We found 62.4% of CSSBs had sugar content per serving that exceeds the daily free sugar intake for adults (25 g) recommended by the WHO. Some of the branded products sold in China had higher sugar content when they were compared with those in Western countries.

CONCLUSIONS

CSSBs in Beijing, China have high sugar and energy content. Reduction in sugar content and serving size of CSSBs and taxation policy on beverages will be beneficial in reducing sugar intake in China.

Using appropriate pre-pregnancy body mass index cut points for obesity in the Chinese population: a retrospective cohort study

BACKGROUND

Appropriate classification of obesity is vital for risk assessment and complication prevention during pregnancy. We aimed to explore which pre-pregnancy BMI cut-offs of obesity, either BMI ≥ 25 kg/m² as recommended by the WHO for Asians or BMI ≥ 28 kg/m² as suggested by the Working Group on Obesity in China (WGOC), best predicts the risk of adverse maternal and perinatal outcomes.

METHODS

We retrospectively reviewed 11,494 medical records for live singleton deliveries in a tertiary center in Guangzhou, China, between January 2013 and December 2016. The primary outcomes included maternal obesity prevalence, adverse maternal and perinatal outcomes. Data were analyzed using the Chi-square test, logistic regression, and diagnostics tests.

RESULTS

Among the study population, 824 (7.2%) were obese according to the WHO criteria for Asian populations, and this would be reduced to 198 (1.7%) based on the criteria of WGOC. Obesity-related adverse maternal and perinatal outcomes were gestational diabetes mellitus, preeclampsia, cesarean section, and large for gestational age (P < 0.05). Compared to the WGOC criterion, the WHO for Asians criterion had a higher Youden index in our assessment of its predictive value in identifying risk of obesity-related adverse outcomes for Chinese pregnant women. Women in the BMI range of 25 to 28 kg/m² are at high risks for adverse maternal and perinatal outcomes, which were similar to women with BMI ≥ 28 kg/m².

CONCLUSIONS

A lower pre-pregnancy BMI cutoff at 25 kg/m² for defining obesity may be appropriate for pregnant women in South China. If WGOC standards are applied to pregnant Chinese populations, a significant proportion of at-risk patients may be missed.

Estimated global overweight and obesity burden in pregnant women based on panel data model

Objective

To estimate the global and country-level burden of overweight and obesity among pregnant women from 2005 to 2014.

Methods

Publicly accessible country-level data were collected from the World Health Organization, the World Bank and the Food and Agricultural Organization. We estimated the number of overweight and obese pregnant women among 184 countries and determined the time-related trend from 2005 to 2014. Based on panel data model, we determined the effects of food energy supply, urbanization, gross national income and female employment on the number of overweight and obese pregnant women.

Results

We estimated that 38.9 million overweight and obese pregnant women and 14.6 million obese pregnant women existed globally in 2014. In upper middle income countries and lower middle income countries, there were sharp increases in the number of overweight and obese pregnant women. In 2014, the percentage of female with overweight and obesity in India was 21.7%, and India had the largest number of overweight and obese pregnant women (4.3 million), which accounted for 11.1% in the world. In the United States of America, a third of women were obese, and the number of obese pregnant women was 1.1 million. In high income countries, caloric supply and urbanization were positively associated with the number of overweight and obese pregnant women. The percentage of employment in agriculture was inversely associated with the number of overweight and obese pregnant women, but only in upper middle income countries and lower middle income countries.

Conclusion

The number of overweight and obese pregnant women has increased in high income and middle income countries. Environmental changes could lead to increased caloric supply and decreased energy expenditure among women. National and local governments should work together to create a healthy food environment.

Implication of miR-612 and miR-1976 in the regulation of TP53 and CD40 and their relationship in the response to specific weight-loss diets

Background

Non-coding RNAs (i.e., miRNAs) play a role in the development of obesity and related comorbidities and the regulation of body weight.

Objective

To identify candidate miRNA biomarkers throughout omics approaches in order to predict the response to specific weight-loss dietary treatments.

Design

Genomic DNA and cDNA isolated from white blood cells of a subset from the RESMENA nutritional intervention study (Low-responders (LR) vs High-responders (HR)) was hybridized in Infinium Human Methylation450 BeadChip and in Illumina Human HT-12 v4 gene expression BeadChips arrays respectively. A bioinformatic prediction of putative target sites of selected miRNAs was performed by applying miRBase algorithms. HEK-293T cells were co-transfected with expression vectors containing the 3’-UTR of candidate genes to validate the binding of miRNAs to its target sites.

Results

134 miRNAs were differentially methylated between HR and LR in the methylation array, whereas 44 miRNAs were differentially expressed between both groups in the expression array. Specifically, miR-1237, miR-1976, miR-642, miR-636, miR-612 and miR-193B were simultaneously hypomethylated and overexpressed in HR. miR-612 and miR-1976 showed greatest differences in methylation and expression levels, respectively. The bioinformatic prediction revealed that TP53 was a putative target gene of miR-612 and CD40 of miR-1976. Moreover, TP53 was downregulated in the expression array when comparing HR vs LR expression levels adjusted by sex, diet, age and baseline weight, and CD40 showed a statistical trend. Furthermore, gene expression levels of TP53 and CD40 in white blood cells, when measured by qPCR, were also downregulated in HR. Finally, miR-612 and miR-1976 potently repressed TP53 and CD40 respectively by targeting its 3’-UTR regions.

Conclusion

miR-612 and miR-1976 levels could be prospective biomarkers of response to specific weight-loss diets and might regulate the gene expression of TP53 and CD40.

Macronutrient Composition of the Australian Population's Diet; Trends from Three National Nutrition Surveys 1983, 1995 and 2012

Although the role of individual macronutrients in the development of obesity remains controversial, changes in macronutrient composition of the diet may have played a causal role in the obesity epidemic. The aim of this analysis was to determine the percentage energy (%E) for protein, carbohydrate and fat of Australian adults' diets over time. Cross-sectional, national nutrition surveys from 1983, 1995 and 2012 assessed diet using one 24 h recall. The prevalence of obesity increased between each survey, from 9.6% to 19.7% and 27.7%. Protein (%E) differed between each survey and contributed 17.7%, 16.8% and 18.3% energy in 1983, 1995 and 2012, respectively (p < 0.001). Carbohydrate (%E) increased from 40.0% in 1983 to 44.9% in 1995 (p < 0.001), with no change in dietary fibre but declined in 2012 to 43.1%. Fat (%E) declined between each survey from 35.3%, 31.9%, to 30.9%, respectively (p < 0.001). Alcohol (%E) has declined for younger adults and men but intake increased for women aged >45 years. Prospective cohort studies with comprehensive assessment of foods consumed, together with measurements of weight and height, will advance the understanding of the relationship between macronutrients and changes in body weight and obesity.

Brown Adipose Tissue Energy Metabolism in Humans

The demonstration of metabolically active brown adipose tissue (BAT) in humans primarily using positron emission tomography coupled to computed tomography (PET/CT) with the glucose tracer 18-fluorodeoxyglucose (18FDG) has renewed the interest of the scientific and medical community in the possible role of BAT as a target for the prevention and treatment of obesity and type 2 diabetes (T2D). Here, we offer a comprehensive review of BAT energy metabolism in humans. Considerable advances in methods to measure BAT energy metabolism, including nonesterified fatty acids (NEFA), chylomicron-triglycerides (TG), oxygen, Krebs cycle rate, and intracellular TG have led to very good quantification of energy substrate metabolism per volume of active BAT in vivo. These studies have also shown that intracellular TG are likely the primary energy source of BAT upon activation by cold. Current estimates of BAT's contribution to energy expenditure range at the lower end of what would be potentially clinically relevant if chronically sustained. Yet, 18FDG PET/CT remains the gold-standard defining method to quantify total BAT volume of activity, used to calculate BAT's total energy expenditure. Unfortunately, BAT glucose metabolism better reflects BAT's insulin sensitivity and blood flow. It is now clear that most glucose taken up by BAT does not fuel mitochondrial oxidative metabolism and that BAT glucose uptake can therefore be disconnected from thermogenesis. Furthermore, BAT thermogenesis is efficiently recruited upon repeated cold exposure, doubling to tripling its total oxidative capacity, with reciprocal reduction of muscle thermogenesis. Recent data suggest that total BAT volume may be much larger than the typically observed 50-150 ml with 18FDG PET/CT. Therefore, the current estimates of total BAT thermogenesis, largely relying on total BAT volume using 18FDG PET/CT, may underestimate the true contribution of BAT to total energy expenditure. Quantification of the contribution of BAT to energy expenditure begs for the development of more integrated whole body in vivo methods.

Anti-obesity potential of Glycyrrhiza uralensis and licochalcone A through induction of adipocyte browning

The main function of brown adipose tissue is to dissipate surplus caloric intake into heat energy by thermogenesis, increasing energy expenditure. Inducible brown adipocytes can develop within white adipose tissue (WAT) through a process referred to as browning. Browning of white fat represents a promising strategy for treatment of obesity and the related complications. We investigated whether Glycyrrhiza uralensis and its ingredients modulated adipogenesis through adipocyte browning using 3T3-L1 adipocytes and a high-fat diet (HFD)-induced obesity mice model. Amongst extracts and fractions of G. uralensis, methyl dichloride (MeCl₂) fraction was the most effective to induce expression of uncoupling protein 1 (UCP1), a fat browning marker, in 3T3-L1 adipocytes. Ingredients of G. uralensis such as licochalcone A (LicoA), isoliquiritigenin, and liquiritigenin induced UCP1 expression in 3T3-L1 adipocytes. After inducing obesity in mice by 6-week HFD, MeCl₂ fraction of G. uralensis or LicoA was intraperitoneally administered for additional 19 days. MeCl₂ fraction or LicoA significantly reduced body weight gain and inguinal fat pad weights. Furthermore, MeCl₂ fraction or LicoA improved metabolic disorders induced by HFD as the treatments decreased serum levels of glucose and cholesterol, and blocked insulin resistance. MeCl₂ fraction or LicoA enhanced expression of brown fat markers such as UCP1, PRDM16, and PGC-1α and increased brown fat phenotype population in inguinal WAT of HFD-fed mice. Our results demonstrate that G. uralensis and LicoA are effective to reduce obesity and to recover metabolic homeostasis by inducing the brown fat phenotype.

Use of Deep Learning to Examine the Association of the Built Environment With Prevalence of Neighborhood Adult Obesity

IMPORTANCE

More than one-third of the adult population in the United States is obese. Obesity has been linked to factors such as genetics, diet, physical activity, and the environment. However, evidence indicating associations between the built environment and obesity has varied across studies and geographical contexts.

OBJECTIVE

To propose an approach for consistent measurement of the features of the built environment (ie, both natural and modified elements of the physical environment) and its association with obesity prevalence to allow for comparison across studies.

DESIGN

The cross-sectional study was conducted from February 14 through October 31, 2017. A convolutional neural network, a deep learning approach, was applied to approximately 150 000 high-resolution satellite images from Google Static Maps API (application programing interface) to extract features of the built environment in Los Angeles, California; Memphis, Tennessee; San Antonio, Texas; and Seattle (representing Seattle, Tacoma, and Bellevue), Washington. Data on adult obesity prevalence were obtained from the Centers for Disease Control and Prevention's 500 Cities project. Regression models were used to quantify the association between the features and obesity prevalence across census tracts.

MAIN OUTCOMES AND MEASURES

Model-estimated obesity prevalence (obesity defined as body mass index ≥30, calculated as weight in kilograms divided by height in meters squared) based on built environment information.

RESULTS

The study included 1695 census tracts in 6 cities. The age-adjusted obesity prevalence was 18.8% (95% CI, 18.6%-18.9%) for Bellevue, 22.4% (95% CI, 22.3%-22.5%) for Seattle, 30.8% (95% CI, 30.6%-31.0%) for Tacoma, 26.7% (95% CI, 26.7%-26.8%) for Los Angeles, 36.3% (95% CI, 36.2%-36.5%) for Memphis, and 32.9% (95% CI, 32.8%-32.9%) for San Antonio. Features of the built environment explained 64.8% (root mean square error [RMSE], 4.3) of the variation in obesity prevalence across all census tracts. Individually, the variation explained was 55.8% (RMSE, 3.2) for Seattle (213 census tracts), 56.1% (RMSE, 4.2) for Los Angeles (993 census tracts), 73.3% (RMSE, 4.5) for Memphis (178 census tracts), and 61.5% (RMSE, 3.5) for San Antonio (311 census tracts).

CONCLUSIONS AND RELEVANCE

This study illustrates that convolutional neural networks can be used to automate the extraction of features of the built environment from satellite images for studying health indicators. Understanding the association between specific features of the built environment and obesity prevalence can lead to structural changes that could encourage physical activity and decreases in obesity prevalence.

Meta-analysis and systematic review of population-based epidemiological studies in idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH) is positively associated with obesity, mostly in young women. The global increase in obesity may influence the burden of IIH. Using the PubMed, Embase, MEDLINE and Web of Science databases, a meta-analysis and systematic review of epidemiological studies of IIH were performed up to June 2017. Temporal changes in IIH incidence were measured, and incidence rates of IIH were correlated with country-specific World Health Organization obesity rates. Prevalence data and shunting rates of IIH were recorded. The quality of epidemiological studies was assessed using the Standards of Reporting of Neurological Disorders (STROND) criteria. In 15 identified studies, there were 889 patients (87% women), mean age 29.8 years. The incidence of IIH ranged from 0.03 to 2.36 per 100 000 per year. The pooled incidence of IIH was 1.20 per 100 000 per year although there was very high heterogeneity (I² 98%). The incidence rates of IIH were correlated with country-specific prevalence of obesity (Spearman's correlation 0.82, P < 0.01). The prevalence of IIH was rarely recorded. A shunting procedure was reported in 8% of patients. STROND criteria were variably reported, median of 26.5 of 43 (range 16-35). IIH is a public health concern as increased obesity prevalence is associated with increased incidence of IIH. A better quality of epidemiological studies is required to improve understanding of IIH and inform health policy for IIH management.

IL-37 Expression Reduces Lean Body Mass in Mice by Reducing Food Intake

The human cytokine interleukin (IL)-37 is an anti-inflammatory member of the IL-1 family of cytokines. Transgenic expression of IL-37 in mice protects them from diet-induced obesity and associated metabolic complications including dyslipidemia, inflammation and insulin resistance. The precise mechanism of action leading to these beneficial metabolic effects is not entirely known. Therefore, we aimed to assess in detail the effect of transgenic IL-37 expression on energy balance, including food intake and energy expenditure. Feeding homozygous IL-37 transgenic mice and wild-type (WT) control mice a high-fat diet (HFD; 45% kcal palm fat) for 6 weeks showed that IL-37 reduced body weight related to a marked decrease in food intake. Subsequent mechanistic studies in mice with heterozygous IL-37 expression versus WT littermates, fed the HFD for 18 weeks, confirmed that IL-37 reduces food intake, which led to a decrease in lean body mass, but did not reduce fat mass and plasma lipid levels or alterations in energy expenditure independent of lean body mass. Taken together, this suggests that IL-37 reduces lean body mass by reducing food intake.

Intervention strategies for preventing excessive gestational weight gain: systematic review and meta-analysis

BACKGROUND

Interventions relevant to energy intake to prevent excessive gestational weight gain in pregnant overweight and obese women are important but scarce. This review synthesized healthy eating and physical activity strategies and their effects on excessive gestational weight gain prevention.

METHODS

Twenty-three randomized controlled trials that included healthy eating and/or physical activity as an intervention in healthy pregnant overweight or obese adult women and gestational weight gain as a primary or secondary outcome were reviewed.

FINDINGS

Heathy eating and/or physical activity (21 studies, n = 6,920 subjects) demonstrated 1.81 kg (95% CI: -3.47, -0.16) of gestational weight gain reduction favouring intervention. Healthy eating (-5.77 kg, 95% CI: -9.34, -2.21, p = 0.02) had a larger effect size than combined healthy eating/physical activity (-0.82 kg, 95% CI: -1.28, -0.36, p = 0.0005) in limiting gestational weight gain. Physical activity did not show a significant pooled effect. Healthy eating with prescribed daily calorie and macronutrient goals significantly limited gestational weight gain by 4.28 kg and 4.23 kg, respectively.

CONCLUSION

Healthy eating and/or physical activity are effective in gestational weight gain control. Healthy eating with calorie and macronutrient goals are especially effective in limiting excessive gestational weight gain among pregnant overweight and obese women.

Metabolic syndrome positively correlates with the risks of atherosclerosis and diabetes in a Chinese population

BACKGROUND

Published studies seldom tested the weight of different waist circumference (WC) cut-off values for the diagnosis of metabolic syndrome (MetS) in predicting clinical outcomes, including cardiovascular disease and diabetes.

METHODS

This is a Chinese population-based cross-sectional study screening subjects from a Health Examination Program since 1999 to 2015. The MetS identification and scores were determined either according to the Adult Treatment Panel III/American Heart Association/National Heart, Lung, and Blood Institute (ATP III/AHA/NHLBI)- or Asian-WC cut-off points. The developments of a higher brachial-ankle pulse wave velocity (baPWV), defined as ≥1400 cm/s, and diabetic-level hyperglycemia, defined as a high fasting glucose level ≥6.99 mmol/L or postprandial glucose level ≧11.10 mmol/L, were surveyed by comparing the areas under receiver operating characteristic curves (AUC-ROC) for both MetS scores.

RESULTS

According to the ATP III/AHA/NHLBI- vs Asian-MetS criteria, 6633 vs 9133 (24.8% vs 34.2%, p < 0.001) subjects were diagnosed as the MetS among 26,735 study subjects with a mean age of 55 ± 12 years. The stepwise increases in baPWV and prevalence of diabetic-level hyperglycemia were associated with both MetS scores after adjusting for age and sex. Both MetS scores yielded similar results for correlation with a higher baPWV (AUC-ROC = 0.685 for ATP III/AHA/HLBI- vs 0.680 for Asian-MetS, p = 0.271) and diabetic-level hyperglycemia (AUC-ROC = 0.791 for ATP III/AHA/HLBI- vs 0.784 for Asian-MetS, p = 0.546).

CONCLUSIONS

In a stepwise manner, both ATP III/AHA/NHLBI- or Asian-MetS scores were strong risk factors for arterial stiffness and diabetes. Through a novel and holistic approach, the performance of the ATP III/AHA/NHLBI-MetS score for the risks of arterial stiffness and diabetes was comparable to the Asian-MetS score among a Chinese population.

Are peptide conjugates the golden therapy against obesity?

Obesity is a worldwide pandemic, which can be fatal for the most extremely affected individuals. Lifestyle interventions such as diet and exercise are largely ineffective and current anti-obesity medications offer little in the way of significant or sustained weight loss. Bariatric surgery is effective, but largely restricted to only a small subset of extremely obese patients. While the hormonal factors mediating sustained weight loss and remission of diabetes by bariatric surgery remain elusive, a new class of polypharmacological drugs shows potential to shrink the gap in efficacy between a surgery and pharmacology. In essence, this new class of drugs combines the beneficial effects of several independent hormones into a single entity, thereby combining their metabolic efficacy to improve systems metabolism. Such unimolecular drugs include single molecules with agonism at the receptors for glucagon, glucagon-like peptide 1 and the glucose-dependent insulinotropic polypeptide. In preclinical studies, these specially tailored multiagonists outperform both their mono-agonist components and current best in class anti-obesity medications. While clinical trials and vigorous safety analyses are ongoing, these drugs are poised to have a transformative effect in anti-obesity therapy and might hopefully lead the way to a new era in weight-loss pharmacology.

Timing of eating in adults across the weight spectrum: Metabolic factors and potential circadian mechanisms

Timing of eating is recognized as a significant contributor to body weight regulation. Disruption of sleep-wake cycles from a predominantly diurnal (daytime) to a delayed (evening) lifestyle leads to altered circadian rhythms and metabolic dysfunction. This article reviews current evidence for timed and delayed eating in individuals of normal weight and those with overweight or obesity: although some findings indicate a benefit of eating earlier in the daytime on weight and/or metabolic outcomes, results have not been uniformly consistent, and more rigorous and longer-duration studies are needed. We also review potential circadian mechanisms underlying the metabolic- and weight-related changes resulting from timed and delayed eating. Further identification of such mechanisms using deep phenotyping is required to determine targets for medical interventions for obesity and for prevention of metabolic syndrome and diabetes, and to inform clinical guidelines regarding eating schedules for management of weight and metabolic disease.

Dietary fats modify vascular fat composition, eNOS localization within lipid rafts and vascular function in obesity

We tested whether dietary fatty acids alter membrane composition shifting localization of signaling pathways within caveolae to determine their role in vascular function. Wild type (WT) and caveolin-1-deficient mice (cav-1 KO), required for vascular caveolae formation, were fed low fat (LF), high saturated fat (HF, 60% kcal from lard), or high-fat diet with 50:50 lard and n-3 polyunsaturated fatty acid-enriched menhaden oil (MO). HF and MO increased body weight and fat in WT but had less effect in cav-1 KO. MO increased unsaturated fatty acids and the unsaturation index of aorta from WT and cav-1 KO. In LF WT aorta, endothelial nitric oxide synthase (eNOS) was localized to cav-1-enriched low-density fractions which shifted to actin-enriched high-density fractions with acetylcholine (ACh). HF and MO shifted eNOS to high-density fractions in WT aorta which was not affected by ACh. In cav-1 KO aorta, eNOS was localized in low-density non-caveolar fractions but not shifted by ACh or diet. Inducible NOS and cyclooxygenase 1/2 were not localized in low-density fractions or affected by diet, ACh or genotype. ACh-induced dilation of gracilis arteries from HF WT was similar to dilation in LF but the NOS component was reduced. In WT and cav-1 KO, dilation to ACh was enhanced by MO through increased role for NOS and cyclooxygenase. We conclude that dietary fats affect vascular fatty acid composition and membrane localization of eNOS but the contribution of eNOS and cyclooxygenase in ACh-mediated vascular responses is independent of lipid rafts.

Metabolic Contrasts Between Youth and Adults With Impaired Glucose Tolerance or Recently Diagnosed Type 2 Diabetes: II. Observations Using the Oral Glucose Tolerance Test

OBJECTIVE

To compare oral glucose tolerance test (OGTT) glucose, C-peptide, and insulin responses and insulin sensitivity in youth and adults with impaired glucose tolerance (IGT) or recently diagnosed type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 66 youth (80.3% with IGT) and 355 adults (70.7% with IGT) underwent a 3-h OGTT to assess 1) insulin sensitivity (1/fasting insulin), 2) C-peptide index (CPI) and insulinogenic index (IGI) over the first 30 min, and 3) glucose, C-peptide, and insulin incremental areas above fasting over the 3-h post-ingestion (incremental glucose [G-iAUC], incremental C-peptide [CP-iAUC], and incremental insulin area under the curve [I-iAUC] responses, respectively).

RESULTS

Fasting, 2-h glucose, and G-iAUC were similar in both age-groups, but youth had ∼50% lower 1/fasting insulin (P < 0.001), 75% higher CPI (mean [95% CI] 0.703 [0.226, 2.183] vs. 0.401 [0.136, 1.183] nmol/mmol; P < 0.001), and more than twofold higher IGI (257.3 [54.5, 1,215.8] vs. 114.8 [28.0, 470.8] pmol/mmol; P < 0.001). Two-hour C-peptide and insulin concentrations, CP-iAUC, and I-iAUC were all higher in youth (all P < 0.001). C-peptide and insulin responses remained significantly greater in youth after adjustment for insulin sensitivity. Within each age-group, individuals with type 2 diabetes versus IGT had significantly lower CPI and IGI with no difference in insulin sensitivity.

CONCLUSIONS

The balance between insulin sensitivity and β-cell responses differs between youth and adults with IGT or recently diagnosed type 2 diabetes. Despite similar postload glucose levels, youth demonstrate greater C-peptide and insulin responses that exceed what is needed to compensate for their lower insulin sensitivity. Longitudinal studies are required to determine whether this feature contributes to a more rapid decline in β-cell function in youth with dysglycemia.

FTO affects food cravings and interacts with age to influence age-related decline in food cravings

The fat mass and obesity associated gene (FTO) was the first gene identified by genome-wide association studies to correlate with higher body mass index (BMI) and increased odds of obesity. FTO remains the locus with the largest and most replicated effect on body weight, but the mechanism whereby FTO affects body weight and the development of obesity is not fully understood. Here we tested whether FTO is associated with differences in food cravings and a key aspect of dopamine function that has been hypothesized to influence food reward mechanisms. Moreover, as food cravings and dopamine function are known to decline with age, we explored effects of age on relations between FTO and food cravings and dopamine function. Seven-eight healthy subjects between 22 and 83years old completed the Food Cravings Questionnaire and underwent genotyping for FTO rs9939609, the first FTO single nucleotide polymorphism associated with obesity. Compared to TT homozygotes, individuals carrying the obesity-susceptible A allele had higher total food cravings, which correlated with higher BMI. Additionally, food cravings declined with age, but this age effect differed across variants of FTO rs9939609: while TT homozygotes showed the typical age-related decline in food cravings, there was no such decline among A carriers. All subjects were scanned with [18F]fallypride PET to assess a recent proposal that at the neurochemical level FTO alters dopamine D2-like receptor (DRD2) function to influence food reward related mechanisms. However, we observed no evidence of FTO effects on DRD2 availability.

Obesity Inequalities According to Place of Birth: The Role of Education

This study examined obesity inequalities according to place of birth and educational attainment in men and in women in Spain. A cross-sectional study was conducted using data from the Spanish National Health Survey 2011–2012 and from the European Health Survey in Spain 2014. We used data for 27,720 adults aged 18–64 years of whom 2431 were immigrants. We used log-binomial regression to quantify the association of place of birth with obesity before and after adjusting for the selected characteristics in women and in men. We found a greater probability of obesity in immigrant women (PR: 1.42; 95% CI: 1.22–1.64) and a lower probability of obesity in immigrant men (PR: 0.73; 95% CI: 0.59–0.89) relative to natives after adjustment. Significant heterogeneity was observed for the association of place of birth and obesity according to education in men (p-interactions = 0.002): Men with lower educational levels (PR: 0.47; 95% CI: 0.26–0.83) have a protective effect against obesity compared with their native counterparts. This study suggests that place of birth may affect obesity in women and in men. However, this effect may be compounded with education differently for women and men.

Neutrophil elastase and myeloperoxidase mRNA expression in overweight and obese subjects

Neutrophil elastase and myeloperoxidase enzymes have been implicated in high-fat diet-induced obesity, insulin resistance (IR) and atherosclerosis in animal models. The aim of the present study was to explore neutrophil elastase and myeloperoxidase mRNA expressions in the peripheral blood leukocytes (PBL) in overweight and obese subjects, and to correlate those mRNA expressions with BMI, IR and cardiovascular biomarkers. In this cross-sectional study, 74 apparently healthy subjects including 22 lean, 27 overweight and 25 obese subjects were recruited. Cardiovascular and metabolic biomarkers were evaluated from fasting blood samples. The mRNA levels of neutrophil elastase and myeloperoxidase genes in the PBL were quantified by real-time PCR. Compared to lean group, the overweight and obese groups showed significant upregulation of both neutrophil elastase (p < 0.001) and myeloperoxidase (p < 0.03) mRNA expressions in the PBL. But no difference was found between overweight and obese groups. The neutrophil elastase and myeloperoxidase mRNA levels showed significant positive correlation with BMI, serum triglyceride, atherogenic index of plasma and 10-year risk of developing cardiovascular disease. But no correlation was found with glucose, insulin or IR. It was concluded that the neutrophil elastase and myeloperoxidase genes are up-regulated in both overweight and obese subjects and are associated with BMI and markers of cardiovascular disease.

The gut microbiome in obesity

Obesity is worldwide epidemic given its rapid growth in global prevalence. Among the risk factors contributing to obesity, human gut microbiome recently emerges with unprecedented intimacy in host metabolism and inflammation. With the advances in sequencing technology, more and more detailed understandings towards the intricate relationships linking gut microbiome and obesity have been continuously disclosed. Herein, we review studies resolving associations between gut microbiome and obesity, and then mechanistic studies tackling the roles played by gut microbes in obesogenic physiology.

Association of obesity, diabetes and hypertension with cognitive impairment in older age

Background

Age-related cognitive impairment is rising in prevalence but is not yet fully characterized in terms of its epidemiology. Here, we aimed to elucidate the role of obesity, diabetes and hypertension as candidate risk factors.

Methods

Original baseline data from 3 studies (OCTOPUS, DECS, SuDoCo) were obtained for secondary analysis of cross-sectional associations of diabetes, hypertension, blood pressure, obesity (body mass index [BMI] ≥30 kg/m²) and BMI with presence of cognitive impairment in log-binomial regression analyses. Cognitive impairment was defined as scoring more than 2 standard deviations below controls on at least one of 5–11 cognitive tests. Underweight participants (BMI<18.5 kg/m²) were excluded. Results were pooled across studies in fixed-effects inverse variance models.

Results

Analyses totaled 1545 participants with a mean age of 61 years (OCTOPUS) to 70 years (SuDoCo). Cognitive impairment was found in 29.0% of participants in DECS, 8.2% in SuDoCo and 45.6% in OCTOPUS. In pooled analyses, after adjustment for age, sex, diabetes and hypertension, obesity was associated with a 1.29-fold increased prevalence of cognitive impairment (risk ratio [RR] 1.29; 95% CI 0.98, 1.72). Each 1 kg/m² increment in BMI was associated with 3% increased prevalence (RR 1.03; 95% CI 1.00, 1.06). None of the remaining risk factors were associated with impairment.

Conclusion

Our results show that older people who are obese have higher prevalence of cognitive impairment compared with normal weight and overweight individuals, and independently of co-morbid hypertension or diabetes. Prospective studies are needed to investigate the temporal relationship of the association.

Environmental Obesogens: Mechanisms and Controversies

Obesity is a worldwide pandemic in adults as well as children and adds greatly to health care costs through its association with type 2 diabetes, metabolic syndrome, cardiovascular disease, and cancers. The prevailing medical view of obesity is that it results from a simple imbalance between caloric intake and energy expenditure. However, numerous other factors are important in the etiology of obesity. The obesogen hypothesis proposes that environmental chemicals termed obesogens promote obesity by acting to increase adipocyte commitment, differentiation, and size by altering metabolic set points or altering the hormonal regulation of appetite and satiety. Many obesogens are endocrine disrupting chemicals that interfere with normal endocrine regulation. Endocrine disrupting obesogens are abundant in our environment, used in everyday products from food packaging to fungicides. In this review, we explore the evidence supporting the obesogen hypothesis, as well as the gaps in our knowledge that are currently preventing a complete understanding of the extent to which obesogens contribute to the obesity pandemic.

Body mass index and risk of all-cause mortality with normoglycemia, impaired fasting glucose and prevalent diabetes: results from the Rural Chinese Cohort Study

BACKGROUND

Previous evidence of an association between body mass index (BMI) and mortality in patients with diabetes was inconsistent. The BMI-mortality association with normal fasting glucose (NFG), impaired fasting glucose (IFG) and prevalent diabetes is still unclear in the Chinese population.

METHODS

We analysed data for 17 252 adults from the Rural Chinese Cohort Study during 2007-2008 and followed for mortality during 2013-2014. Participants were classified with NFG, IFG and diabetes according to baseline measurement values of fasting glucose and self-reported diabetes. Multivariable Cox proportional hazard models were used to calculate HRs and 95% CIs across BMI categories by glycemic status.

RESULTS

During the 6-year follow-up, 1109 participants died (563/10 181 with NFG, 349/5572 with IFG and 197/1499 with diabetes). The BMI-mortality association was curvilinear, with low BMI (even in normal range) associated with increased mortality regardless of glycemic status. In adjusted Cox models, risk of mortality showed a decreasing trend with BMI≤18 kg/m², 18<BMI≤20 kg/m² and 20<BMI≤22 kg/m² vs 22<BMI≤24 kg/m²: HR 2.83 (95% CI 1.78 to 4.51), 2.05 (1.46 to 2.87) and 1.45 (1.10 to 1.90), respectively, for NFG; 2.53 (1.25 to 5.14), 1.36 (0.86 to 2.14) and 1.09 (0.76 to 1.57), respectively, for IFG; and 4.03 (1.42 to 11.50), 2.00 (1.05 to 3.80) and 1.52 (0.88 to 2.60), respectively, for diabetes. The risk of mortality was lower for patients with diabetes who were overweight or obese versus normal weight.

CONCLUSIONS

Low BMI was associated with increased mortality regardless of glycemic status. Future studies are needed to explain the 'obesity paradox' in patients with diabetes.

Dietary Fibre as a Unifying Remedy for the Whole Spectrum of Obesity-Associated Cardiovascular Risk

Obesity is a pandemic carrying the heavy burden of multiple and serious co-morbidities including metabolic syndrome, type 2 diabetes and cardiovascular diseases. The pathophysiological processes leading to the accumulation of body fat slowly evolve to fat accumulation in other body compartments than subcutaneous tissue. This abnormal fat deposition determines insulin resistance which in turn causes blood glucose and lipid metabolism derangement, non-alcoholic fatty liver disease, hypertension, and metabolic syndrome. All these conditions contribute to increase the cardiovascular risk of obese people. Several randomized clinical trials demonstrated that moderate weight loss (5⁻10%) in obese patients improves obesity-related metabolic risk factors and coexisting disorders. Therefore, nutritional strategies able to facilitate weight management, and in the meantime positively influence obesity-associated cardiovascular risk factors, should be implemented. To this aim, a suitable option could be dietary fibres that may also act independently of weight loss. The present narrative review summarizes the current evidence about the effects of dietary fibres on weight management in obese people. Moreover, all of the different cardiovascular risk factors are individually considered and evidence on cardiovascular outcomes is summarized. We also describe the plausible mechanisms by which different dietary fibres could modulate cardio-metabolic risk factors. Overall, despite both epidemiological and intervention studies on weight loss that show statistically significant but negligible clinical effects, dietary fibres seem to have a beneficial impact on main pathophysiological pathways involved in cardiovascular risk (i.e., insulin resistance, renin-angiotensin, and sympathetic nervous systems). Although the evidence is not conclusive, this suggests that fibre would be a suitable option to counteract obesity-related cardio-metabolic diseases also independently of weight loss. However, evidence is not consistent for the different risk factors, with clear beneficial effects shown on blood glucose metabolism and Low Density Lipoprotein (LDL) cholesterol while there is fewer, and less consistent data shown on plasma triglyceride and blood pressure. Ascribing the beneficial effect of some foods (i.e., fruits and vegetables) solely to their fibre content requires more investigation on the pathophysiological role of other dietary components, such as polyphenols.

Rationale and Protocol for a Randomized Controlled Trial Comparing Fast versus Slow Weight Loss in Postmenopausal Women with Obesity-The TEMPO Diet Trial

Very low energy diets (VLEDs), commonly achieved by replacing all food with meal replacement products and which result in fast weight loss, are the most effective dietary obesity treatment available. VLEDs are also cheaper to administer than conventional, food-based diets, which result in slow weight loss. Despite being effective and affordable, these diets are underutilized by healthcare professionals, possibly due to concerns about potential adverse effects on body composition and eating disorder behaviors. This paper describes the rationale and detailed protocol for the TEMPO Diet Trial (Type of Energy Manipulation for Promoting optimal metabolic health and body composition in Obesity), in a randomized controlled trial comparing the long-term (3-year) effects of fast versus slow weight loss. One hundred and one post-menopausal women aged 45–65 years with a body mass index of 30–40 kg/m² were randomized to either: (1) 16 weeks of fast weight loss, achieved by a total meal replacement diet, followed by slow weight loss (as for the SLOW intervention) for the remaining time up until 52 weeks (“FAST” intervention), or (2) 52 weeks of slow weight loss, achieved by a conventional, food-based diet (“SLOW” intervention). Parameters of body composition, cardiometabolic health, eating disorder behaviors and psychology, and adaptive responses to energy restriction were measured throughout the 3-year trial.

Contribution of maternal overweight and obesity to the occurrence of adverse pregnancy outcomes

AIMS

Maternal overweight and obesity in pregnancy are known to increase the risk of a range of complications and adverse pregnancy outcomes. This study estimates the population-level contribution of maternal overweight and obesity to adverse pregnancy outcomes.

METHODS

Data derived from the Australian Capital Territory (ACT) Maternal and Perinatal Data Collection were analysed. A total of 24 161 women who had a singleton birth in 2009-2015, with maternal weight and height information available, were included. In this study, the association between risk factors and outcomes was investigated using multilevel regression modelling. Based on model predictions under various hypothetical maternal weight scenarios, the number and proportion of adverse perinatal outcomes that could be potentially prevented were estimated.

RESULTS

Maternal overweight and obesity were associated with increased risks of gestational diabetes mellitus (GDM), pre-eclampsia, caesarean delivery, preterm birth (PTB), large for gestational age (LGA) and admission to the special care nursery or neonatal intensive care unit (SCN/NICU). The estimated proportions of adverse pregnancy outcomes attributable to overweight and obesity in pregnancy are 29.3% for GDM, 36.2% for pre-eclampsia, 15.5% for caesarean delivery, 21.6% for longer antenatal stay in hospital (≥2 days), 16.3% for extreme PTB, 25.2% for LGA and 6.5% for SCN/NICU admission.

CONCLUSIONS

Maternal overweight and obesity contribute to a large proportion of obstetric complications and adverse outcomes in the ACT. Effective intervention strategies to reduce the prevalence of overweight and obesity in pregnant women could have significant beneficial effects on pregnancy outcomes.

Onco-metabolism: defining the prognostic significance of obesity and diabetes in women with brain metastases from breast cancer

PURPOSE

Metabolic dysregulation has been implicated as a molecular driver of breast cancer in preclinical studies, especially with respect to metastases. We hypothesized that abnormalities in patient metabolism, such as obesity and diabetes, may drive outcomes in breast cancer patients with brain metastases.

METHODS

We retrospectively identified 84 consecutive patients with brain metastases from breast cancer treated with intracranial radiation therapy. Radiation was delivered as whole-brain radiation to a median dose of 3000 cGy or stereotactic radiosurgery to a median dose of 2100 cGy. Kaplan Meier curves were generated for overall survival (OS) data and Mantel-Cox regression was performed to detect differences in groups.

RESULTS

At analysis, 81 survival events had occurred and the median OS for the entire cohort was 21.7 months. Despite similar modified graded prognostic assessments, resection rates, and receptor status, BMI ≥ 25 kg/m² (n = 45) was associated with decreased median OS (13.7 vs. 30.6 months; p < 0.001) and median intracranial progression-free survival (PFS) (7.4 vs. 10.9 months; p = 0.04) compared to patients with BMI < 25 kg/m² (n = 39). Similar trends were observed among all three types of breast cancer. Patients with diabetes (n = 17) had decreased median OS (11.8 vs. 26.2 months; p < 0.001) and median intracranial PFS (4.5 vs. 10.3 months; p = 0.001) compared to non-diabetics (n = 67). On multivariate analysis, both BMI ≥ 25 kg/m² [HR 2.35 (1.39-3.98); p = 0.002] and diabetes [HR 2.77 (1.454-5.274); p = 0.002] were associated with increased mortality.

CONCLUSIONS

Elevated BMI or diabetes may negatively impact both overall survival and local control in patients with brain metastases from breast cancer, highlighting the importance of the translational development of therapeutic metabolic interventions. Given its prognostic significance, BMI should be used as a stratification in future clinical trial design in this patient population.

Identifying usual food choices at meals in overweight and obese study volunteers: implications for dietary advice

Understanding food choices made for meals in overweight and obese individuals may aid strategies for weight loss tailored to their eating habits. However, limited studies have explored food choices at meal occasions. The aim of this study was to identify the usual food choices for meals of overweight and obese volunteers for a weight-loss trial. A cross-sectional analysis was performed using screening diet history data from a 12-month weight-loss trial (the HealthTrack study). A descriptive data mining tool, the Apriori algorithm of association rules, was applied to identify food choices at meal occasions using a nested hierarchical food group classification system. Overall, 432 breakfasts, 428 lunches, 432 dinners and 433 others (meals) were identified from the intake data (n 433 participants). A total of 142 items of closely related food clusters were identified at three food group levels. At the first sub-food group level, bread emerged as central to food combinations at lunch, but unprocessed meat appeared for this at dinner. The dinner meal was characterised by more varieties of vegetables and of foods in general. The definitions of food groups played a pivotal role in identifying food choice patterns at main meals. Given the large number of foods available, having an understanding of eating patterns in which key foods drive overall meal content can help translate and develop novel dietary strategies for weight loss at the individual level.

Important but far away: adolescents' beliefs, awareness and experiences of fertility and preconception health

OBJECTIVES

The aim was to explore adolescents' beliefs and awareness regarding fertility and preconception health, as well as their views and experiences of information about fertility and preconception health directed at their age group.

METHODS

We performed seven semi-structured focus group interviews among upper secondary school students (n = 47) aged 16-18 years in two Swedish counties. Data were analysed by qualitative content analysis.

RESULTS

One theme ('important but far away') and five categories ('starting a family far down on the list'; 'high awareness but patchy knowledge of fertility and preconception health'; 'gender roles influence beliefs about fertility and preconception health'; 'wish to preserve fertility and preconception health in order to keep the door to procreation open'; 'no panacea - early and continuous education about fertility and preconception health') emerged from the interviews. Participants recognised the importance of preconception health and were highly aware of the overall importance of a healthy lifestyle. Their knowledge, however, was patchy and they had difficulties relating to fertility and preconception health on a personal and behavioural level. Participants wanted more information but had heterogeneous beliefs about when, where and how this information should be given.

CONCLUSION

The adolescents wanted information on fertility and preconception health to be delivered repeatedly as well as through different sources.

Impact of a Healthy Weight Intervention Embedded Within a National Home Visiting Program on the Home Food Environment

Purpose: To determine whether a lifestyle intervention embedded within Parents as Teachers (PAT), a national child development and parenting home visiting program, helped families make food-related home environment changes.

Design: Secondary data analysis of a stratified randomized pragmatic trial. (Trial Registration: This study is registered at www.clinicaltrials.gov NCT01567033).

Setting: Participant homes in St. Louis, Missouri.

Subjects: Women (n = 179 with pre-post data, of 230 with baseline) participating in standard PAT, with overweight or obesity, and at least one preschool child with BMI percentile ≥60%.

Intervention: PAT + Healthy Eating and Active Living Taught at Home (HEALTH), embedded elements of the Diabetes Prevention Program within the standard PAT curriculum. PAT + HEALTH addressed specific behaviors that impact caloric intake (e.g., sugar-sweetened beverages), focusing on behavioral and environmental strategies. Consistent with PAT practice, the frequency, number, and focus (i.e., time spent on intervention components) of home visits were determined by the family's needs; dose structure was flexible [on average intervention: 23 (SD = 9), usual care: 13 (SD = 6) visits].

Measures: Food availability/accessibility and distractions in the home were assessed with items drawn largely from the HomeSTEAD Survey.

Analysis: Generalized estimating equations (GEEs) were used to test equality of changes between baseline and 24 months in the intervention and usual care groups.

Results: The only significant difference in the pattern of change between usual care and intervention was soda availability/accessibility (p = 0.013).

Conclusion: This embedded intervention successfully reduced availability/accessibility of sugar-sweetened beverages in the home. However, given the limited impact on other food-related home environment factors, future interventions could seek to more effectively intervene on all aspects of the home environment.

Understanding the impact of commonly utilized, non-insulin, glucose-lowering drugs on body weight in patients with type 2 diabetes

INTRODUCTION

The majority of patients with type 2 diabetes also have obesity. Obesity increases the risk of developing diabetes and is associated with worsened glycemic control and increased morbidity and mortality in individuals with diabetes. Sustained weight loss is associated with improved glycemic control, potential for diabetes remission, and decreased medical expenditures.

AREAS COVERED

Herein, the impact of commonly utilized, non-insulin, glucose-lowering drugs on body weight in patients with type 2 diabetes is discussed. The weight change magnitudes, mechanisms, and any within-class differences are also explored.

EXPERT OPINION

The weight impact of diabetes medications should be considered when designing treatment regimens, especially in patients who are overweight or have obesity. Lifestyle modification is paramount for optimal diabetes management. Therapeutic regimens should ideally be designed to maximize weight loss and at least minimize or avoid weight gain. Future glucose-lowering medications should continue to offer improvement in cardiovascular risk factors, including weight, in order to be accepted into the armamentarium of diabetes therapy. Therapeutic regimens should be designed to help patients with diabetes and obesity achieve both glycemic and weight goals. Management of these disease states is expected to become increasingly integrated.

The importance of healthy dietary patterns in chronic disease prevention

The prevalence of chronic diseases in the United States and around the world is very high and not sustainable by most health care systems. While the etiology is complex, many chronic diseases are preventable through life long practices of adhering to healthy dietary patterns, engaging in physical activity and maintaining acceptable weight. Healthy dietary patterns were defined in the 2015 Dietary Guidelines Advisory Committee Scientific Report as diets that are high in fruits, vegetables, whole grains, low and non-fat dairy and lean protein. Other characteristics of healthy dietary patterns are that they are low in saturated fat, trans fat, sodium and added sugars. The preponderance of evidence to date suggests that healthy dietary patterns reduce the risk of the major diet-related chronic diseases, such as diabetes, cardiovascular disease and some cancers. While several methods exist for assessing dietary patterns in population studies, those that characterize dietary patterns using a priori scoring systems of indices, such as the Healthy Eating Index, may be of the most value because they offer a consistent metric that can be applied across multiple studies. It follows that consistency in methods then allows comparisons of results across populations. The nutrition science community can play a major leadership role in national and global health by promoting access to the ability of all population groups to consume a healthy dietary pattern.

The relationship between sleep duration and obesity risk among school students: a cross-sectional study in Zhejiang, China

Background

Obesity has been identified as a major risk factor for a large number of chronic diseases. Understanding factors related to adolescent obesity is critical for prevention of chronic diseases. The associations between sleep duration and obesity among adolescents in the existing literature are controversial. Our study was designed to determine the prevalence of short sleep duration, and assess the association of sleep duration and obesity, among middle and high school students in Zhejiang, China.

Methods

18,403 Students in 442 schools were recruited and surveyed using an anonymous, self-administered questionnaires. Weighted multivariable logistic regression models were used for data analyses.

Results

The mean (SD) age of the students was 15.9 (1.8) years. 49.7% of students were girls. The mean (SD) height and weight were 166.2 (8.5) cm and 54.6 (11.1) kg, respectively. The overall prevalence of obesity and overweight were 3.4% (95% CI: 3.0–3.8) and 7.8% (95% CI: 7.4–8.3), respectively. The overall prevalence of short sleep duration among students was 66.0% (95% CI: 63.8–68.1), higher among girls than boys (69.8% vs. 62.1%) (P < 0.0001). The figures for middle school, academic high school, and vocational high school were 59.0, 82.4 and 59.7%, respectively (P < 0.0001). As compared with girls who sleep 8 h per day (reference), the odds ratios (95% CI) of obesity for girls who sleep < 7 h, 7 h, 9 h and ≥ 10 h were 1.97 (1.15–3.38), 1.90 (1.18–3.04), 1.38 (0.86–2.20) and 2.12 (1.22–3.67) respectively, after adjustment for socio-demographic status, lifestyle factors, and mental health. The corresponding figures among boys were 1.45 (0.97–2.16), 1.13 (0.81–1.57), 1.25 (0.89–1.74), and 1.12 (0.81–1.54), respectively.

Conclusions

Insufficient sleep is prevalent among students in Zhejiang China. A U-shaped relationship was found between sleep duration and obesity risk among girls, with the lowest risk among those who slept for 8 h, but not among boys. Adequate sleep duration may be an important component of obesity prevention initiatives among adolescents.

Electronic supplementary material

The online version of this article (10.1186/s12986-018-0285-8) contains supplementary material, which is available to authorized users.

Recent advances in understanding body weight homeostasis in humans

Presently, control of body weight is assumed to exist, but there is no consensus framework of body weight homeostasis. Three different models have been proposed, with a "set point" suggesting (i) a more or less tight and (ii) symmetric or asymmetric biological control of body weight resulting from feedback loops from peripheral organs and tissues (e.g. leptin secreted from adipose tissue) to a central control system within the hypothalamus. Alternatively, a "settling point" rather than a set point reflects metabolic adaptations to energy imbalance without any need for feedback control. Finally, the "dual intervention point" model combines both paradigms with two set points and a settling point between them. In humans, observational studies on large populations do not provide consistent evidence for a biological control of body weight, which, if it exists, may be overridden by the influences of the obesogenic environment and culture on personal behavior and experiences. To re-address the issue of body weight homeostasis, there is a need for targeted protocols based on sound concepts, e.g. lean rather than overweight subjects should be investigated before, during, and after weight loss and weight regain. In addition, improved methods and a multi-level-multi-systemic approach are needed to address the associations (i) between masses of individual body components and (ii) between masses and metabolic functions in the contexts of neurohumoral control and systemic effects. In the future, simplifications and the use of crude and non-biological phenotypes (i.e. body mass index and waist circumference) should be avoided. Since changes in body weight follow the mismatch between tightly controlled energy expenditure at loosely controlled energy intake, control (or even a set point) is more likely to be about energy expenditure rather than about body weight itself.

Trends in Obesity and Risk of Cardiovascular Disease

Purpose of review

The obesity epidemic is a global health crisis of staggering proportion. Excess body weight is a major risk factor for the development of cardiovascular disease (CVD). We review temporal trends in obesity rates, pertinent pathophysiology to understand mechanisms of disease, and treatment strategies in the context of reducing cardiovascular risk.

Recent findings

The prevalence of obesity is increasing in recent decades and is driven by a complex interplay of economic, environmental, and biological factors. In developed countries, changes in foodintake, such as increased consumption of energy-dense and added sugar have contributed significantly to weight gain. Single nucleotide variations in genes and alterations in the gut microbiome have been associated with the obese phenotype. The description of an obesity paradox in patients with CVD may have several explanations, including limitations of body mass index (BMI) to assess adiposity, selection bias, and lead-time bias with earlier onset of disease. Evidence-based treatments for weight loss include lifestyle intervention, pharmacotherapy, and bariatric surgery. Data on the long-term effects of these therapies on cardiovascular risk are limited.

Summary

Overweight and obesity are associated with increased cardiovascular morbidity and mortality over the lifespan. Despite our increasing understanding of biological and environmental drivers of obesity, more work is needed in developing effective prevention strategies and implementation of evidence-based treatments to promote cardiovascular health and reduce cardiovascular risk. Ultimately, efforts to prevent and postpone cardiovascular morbidity should include focus on maintenance of normal BMI (primordial prevention) for a longer and healthier life, free of CVD.

Recruitment Strategies for a Randomised Controlled Trial Comparing Fast Versus Slow Weight Loss in Postmenopausal Women with Obesity-The TEMPO Diet Trial

Current research around effective recruitment strategies for clinical trials of dietary obesity treatments have largely focused on younger adults, and thus may not be applicable to older populations. The TEMPO Diet Trial (Type of Energy Manipulation for Promoting optimal metabolic health and body composition in Obesity) is a randomised controlled trial comparing the long-term effects of fast versus slow weight loss on body composition and cardio-metabolic health in postmenopausal women with obesity. This paper addresses the recruitment strategies used to enrol participants into this trial and evaluates their relative effectiveness. 101 post-menopausal women aged 45–65 years, with a body mass index of 30–40 kg/m² were recruited and randomised to either fast or slow weight loss. Multiple strategies were used to recruit participants. The total time cost (labour) and monetary cost per randomised participant from each recruitment strategy was estimated, with lower values indicating greater cost-effectiveness and higher values indicating poorer cost-effectiveness. The most cost-effective recruitment strategy was word of mouth, followed (at equal second place) by free publicity on TV and radio, and printed advertorials, albeit these avenues only yielded 26/101 participants. Intermediate cost-effective recruitment strategies were flyer distribution at community events, hospitals and a local tertiary education campus, internet-based strategies, and clinical trial databases and intranets, which recruited a further 40/101 participants. The least cost-effective recruitment strategy was flyer distribution to local health service centres and residential mailboxes, and referrals from healthcare professionals were not effective. Recruiting for clinical trials involving postmenopausal women could benefit from a combination of recruitment strategies, with an emphasis on word of mouth and free publicity via radio, TV, and print media, as well as strategic placement of flyers, supplemented with internet-based strategies, databases and intranets if a greater yield of participants is needed.

Telmisartan prevents diet-induced obesity and preserves leptin transport across the blood-brain barrier in high-fat diet-fed mice

Obesity is a global health problem and treatment options are still insufficient. When chronically treated with the angiotensin II receptor blocker telmisartan (TEL), rodents do not develop diet-induced obesity (DIO). However, the underlying mechanism for this is still unclear. Here we investigated whether TEL prevents leptin resistance by enhancing leptin uptake across the blood-brain barrier (BBB). To address this question, we fed C57BL/6 mice a high-fat diet (HFD) and treated them daily with TEL by oral gavage. In addition to broadly characterizing the metabolism of leptin, we determined leptin uptake into the brain by measuring BBB transport of radioactively labeled leptin after long-term and short-term TEL treatment. Additionally, we assessed BBB integrity in response to angiotensin II in vitro and in vivo. We found that HFD markedly increased body weight, energy intake, and leptin concentration but that this effect was abolished under TEL treatment. Furthermore, glucose control and, most importantly, leptin uptake across the BBB were impaired in mice on HFD, but, again, both were preserved under TEL treatment. BBB integrity was not impaired due to angiotensin II or blocking of angiotensin II receptors. However, TEL did not exhibit an acute effect on leptin uptake across the BBB. Our results confirm that TEL prevents DIO and show that TEL preserves leptin transport and thereby prevents leptin resistance. We conclude that the preservation of leptin sensitivity is, however, more a consequence than the cause of TEL preventing body weight gain.

A Pilot Study of Iyengar Yoga for Pediatric Obesity: Effects on Gait and Emotional Functioning

Obesity negatively impacts the kinematics and kinetics of the lower extremities in children and adolescents. Although yoga has the potential to provide several distinct benefits for children with obesity, this is the first study to examine the benefits of yoga for gait (primary outcome) in youths with obesity. Secondary outcomes included health-related quality of life (HRQoL), physical activity, and pain. Feasibility and acceptability were also assessed. Nine youths (11⁻17 years) participated in an eight-week Iyengar yoga intervention (bi-weekly 1-h classes). Gait, HRQOL (self and parent-proxy reports), and physical activity were assessed at baseline and post-yoga. Pain was self-reported at the beginning of each class. Significant improvements were found in multiple gait parameters, including hip, knee, and ankle motion and moments. Self-reported and parent-proxy reports of emotional functioning significantly improved. Time spent in physical activity and weight did not change. This study demonstrates that a relatively brief, non-invasive Iyengar yoga intervention can result in improved malalignment of the lower extremities during ambulation, as well as in clinically meaningful improvements in emotional functioning. This study extends current evidence that supports a role for yoga in pediatric obesity.