To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
In recent years, obesity is a growing pandemic in the world and has likely contributed to increasing the incidence of obesity related diseases. Fat mass and obesity associated gene (FTO) is the first gene discovered which has close connection with fat. Recent studies suggested FTO gene has played an important role in the molecular mechanisms of many diseases. Obesity is considered to be a hereditary disease and it can evoke many kinds of diseases, including polycystic ovary syndrome (PCOS), type 2 diabetes mellitus (T2DM), cancer, etc., whose exact possible molecular mechanisms responsible for the effect of FTO on obesity and obesity related diseases remain largely unknown. In this review, we comprehensively discuss the correlation between FTO gene and obesity, cancer, PCOS, T2DM, as well as the molecular mechanism involved in these diseases.
Animal studies have shown that capsaicin plays a positive role in weight management. However, the results in human research are controversial. Therefore, the present systematic review and meta-analysis aimed to evaluate the effect of capsaicin on weight loss in adults. We searched PubMed, Embase, China Biomedical Literature Database (CBM), Cochrane library and clinical registration center, identifying all randomized controlled trials (RCTs) published in English and Chinese to May 3, 2022. A random effect model was used to calculate the weighted mean difference (WMD) and 95% confidence interval (CI). Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Statistical analyses were performed using STATA version 15.1. P <0.05 were considered as statistically significant. From 2377 retrieved studies, 15 studies were finally included in the meta-analyses. Fifteen RCTs with 762 individuals were included in our meta-analysis. Compared with the control group, the supplementation of capsaicin resulted in significant reduction on body mass index (BMI) (WMD: -0.25 kg/m2, 95%CI=-0.35∼-0.15 kg/m2, P<0.05), body weight (BW) (WMD: -0.51 kg, 95%CI=-0.86∼-0.15 kg, P<0.05) and waist circumference (WC) (WMD: -1.12 cm, 95%CI=-2.00∼-0.24 cm, P<0.05). We found no detrimental effect of capsaicin on waist-to-hip ratio (WHR) (WMD: -0.05, 95%CI=-0.17∼0.06, P>0.05). The current meta-analysis suggests that capsaicin supplementation may have rather modest effects in reducing BMI, BW and WC for overweight or obese individuals.
We aimed to investigate the association of metabolic obesity phenotypes with all-cause mortality risk in a rural Chinese population. This prospective cohort study enrolled 15 704 Chinese adults (38·86 % men) with a median age of 51·00 (interquartile range: 41·00–60·00) at baseline (2007–2008) and followed up during 2013–2014. Obesity was defined by waist circumference (WC: ≥ 90 cm for men and ≥ 80 cm for women) or waist-to-height ratio (WHtR: ≥ 0·5). The hazard ratio (HR) and 95 % CI for the risk of all-cause mortality related to metabolic obesity phenotypes were calculated using the Cox hazards regression model. During a median follow-up of 6·01 years, 864 deaths were identified. When obesity was defined by WC, the prevalence of participants with metabolically healthy non-obesity (MHNO), metabolically healthy obesity (MHO), metabolically unhealthy non-obesity (MUNO) and metabolically unhealthy obesity (MUO) at baseline was 12·12 %, 2·80 %, 41·93 % and 43·15 %, respectively. After adjusting for age, sex, alcohol drinking, smoking, physical activity and education, the risk of all-cause mortality was higher with both MUNO (HR = 1·20, 95 % CI 1·14, 1·26) and MUO (HR = 1·20, 95 % CI 1·13, 1·27) v. MHNO, but the risk was not statistically significant with MHO (HR = 0·99, 95 % CI 0·89, 1·10). This result remained consistent when stratified by sex. Defining obesity by WHtR gave similar results. MHO does not suggest a greater risk of all-cause mortality compared to MHNO, but participants with metabolic abnormality, with or without obesity, have a higher risk of all-cause mortality. These results should be cautiously interpreted as the representation of MHO is small.
To examine the trajectories of BMI in Indonesian adults from 1993 to 2014, investigating different patterns by sex and birth cohort.
Longitudinal study: secondary data analysis of the Indonesian Family Life Survey, a large-scale population-based longitudinal study, had their height and weight measured up to five times throughout the 21-year study period (1993–2014). The change in BMI across time was estimated using group-based trajectory models, then differences by sex and birth cohort were investigated using random effect (mixed) models.
Thirteen out of twenty-seven provinces in Indonesia.
Indonesian adults aged 19 years and older (n 42 537) were included in the analysis.
Mean BMI in adults increased between 1993 (21·4 kg/m2) and 2014 (23·5 kg/m2). The group-based trajectory model found three distinct groups with mean BMI increasing more rapidly in the most recent time periods. The first group (56·7 % of participants) had a mean BMI entirely within the normal weight range; the second group (34·7 %) started in the normal weight category and were obese, on average by the end of the study period; and the third group (8·6 %) were always in the obese category, on average. The shape of these three trajectories differed by gender (P < 0·001) and birth cohort (P < 0·001).
The mean BMI among Indonesian adults has increased between 1993 and 2014, driven by those in the most recent birth cohorts. Our findings support the urgent need for targeted overweight and obesity prevention and intervention programmes in Indonesia.
This study aimed to assess the validity of mid-arm circumference (MAC), also known as mid-upper arm circumference (MUAC) for classification of high body fatness in Namibian adolescent girls and women, and to test whether classification accuracy of MUAC was higher than the traditional simple proxy for high fatness, the BMI. In 206 adolescent girls aged 13–19 years, and 207 adult women aged 20-40 years we defined obesity conventionally (BMI-for-age Z score ≥2.00, adolescents; adults BMI≥30.0 kg/m2), and also defined obesity using published MAC cut-off values. Deuterium oxide dilution was used to measure TBW to define high body fat percentage (≥30% in the adolescents, ≥38% in the adults), and we compared the ability of BMI and MAC to classify high body fatness correctly using sensitivity, specificity, and predictive values. In the adolescents, obesity prevalence was 9.2% (19/206) using the BMI-for-age and 63.2% (131/206) by TBW; sensitivity of BMI-for-age was 14.5% (95% CI 9.1 to 22.0%) but was improved significantly using MAC of 22.6cm (sensitivity 96.9%; 95% CI 92.1% to 99.3%). In the adults, obesity prevalence was 30.4% (63/207) using BMI and 57.0% (118/207) using TBW, and sensitivity of BMI was 52.5% (95% CI 43.6 to 62.2%), but using a MAC of 30.6cm sensitivity was 72.8% (95% CI 66.4 to 82.6%. Surveillance of obesity in African adolescent girls and adult women is likely to be improved substantially by use of MAC as an alternative to the BMI for age and BMI.
Chapter 3 focuses specifically on research findings for how obesity, opioid use disorder, and depression in older adults are impacted and shaped by the four socials. The wide range of research contexts and methods are highlighted to provide a clear understanding of the scope of work in these areas.
Obesity is highly prevalent and disabling, especially in individuals with severe mental illness including bipolar disorders (BD). The brain is a target organ for both obesity and BD. Yet, we do not understand how cortical brain alterations in BD and obesity interact.
We obtained body mass index (BMI) and MRI-derived regional cortical thickness, surface area from 1231 BD and 1601 control individuals from 13 countries within the ENIGMA-BD Working Group. We jointly modeled the statistical effects of BD and BMI on brain structure using mixed effects and tested for interaction and mediation. We also investigated the impact of medications on the BMI-related associations.
BMI and BD additively impacted the structure of many of the same brain regions. Both BMI and BD were negatively associated with cortical thickness, but not surface area. In most regions the number of jointly used psychiatric medication classes remained associated with lower cortical thickness when controlling for BMI. In a single region, fusiform gyrus, about a third of the negative association between number of jointly used psychiatric medications and cortical thickness was mediated by association between the number of medications and higher BMI.
We confirmed consistent associations between higher BMI and lower cortical thickness, but not surface area, across the cerebral mantle, in regions which were also associated with BD. Higher BMI in people with BD indicated more pronounced brain alterations. BMI is important for understanding the neuroanatomical changes in BD and the effects of psychiatric medications on the brain.
To examine the governance of the food and nutrition policy space with particular reference to interests and power among stakeholders.
We followed a case study research design to conduct a nutrition policy analysis. We triangulated three sources of data: key-informant interviews, learning journey and relevant policy documents (2010–2020). This study is grounded in a conceptual framework focused on power.
Key informants (n 28) drawn from policy stakeholders from government (Health, Agriculture, Trade and Industry), academia, civil society, development partners, civil society organisation (CSO) and private sector in Accra and Kumasi.
Power relations generated tensions, leading to weak multi-sectoral coordination among actors within the nutrition policy space. Governance and funding issues were identified as reasons for the weak multi-sectoral coordination. Formal power rested with government institutions while the private sector and CSO pushed to be invited during policy formulation. Visible stakeholders from industry were trade oriented and held a common interest of profit-making; they sought to receive support from government in order to be more competitive. There were no observed structures at the subnational levels for effective link with the national level.
Formal responsibility for decision making within the nutrition and food policy space rested with the health sector and bringing on board nutrition-related sectors remained a challenge due to power tensions. Establishing a National Nutrition Council, with structures at the subnational level, will strengthen policy coordination and implementation. Taxation of sugar-sweetened beverages could provide a fund generation avenue for coordination of programmes to curb obesity.
A 31-year-old nulligravida with a body mass index (BMI) of 42 kg/m2 is referred by her primary care provider to your high-risk obstetrics clinic for preconception counseling. Prior to the consultation, you highlight to your obstetric trainee that motivational interviewing with nonstigmatizing terminology avoids negative influences on mood and self-esteem, promoting patient uptake of weight management strategies and a healthy lifestyle.
The cornerstone of obesity treatment is behavioural weight management, resulting in significant improvements in cardio-metabolic and psychosocial health. However, there is ongoing concern that dietary interventions used for weight management may precipitate the development of eating disorders. Systematic reviews demonstrate that, while for most participants medically supervised obesity treatment improves risk scores related to eating disorders, a subset of people who undergo obesity treatment may have poor outcomes for eating disorders. This review summarises the background and rationale for the formation of the Eating Disorders In weight-related Therapy (EDIT) Collaboration. The EDIT Collaboration will explore the complex risk factor interactions that precede changes to eating disorder risk following weight management. In this review, we also outline the programme of work and design of studies for the EDIT Collaboration, including expected knowledge gains. The EDIT studies explore risk factors and the interactions between them using individual-level data from international weight management trials. Combining all available data on eating disorder risk from weight management trials will allow sufficient sample size to interrogate our hypothesis: that individuals undertaking weight management interventions will vary in their eating disorder risk profile, on the basis of personal characteristics and intervention strategies available to them. The collaboration includes the integration of health consumers in project development and translation. An important knowledge gain from this project is a comprehensive understanding of the impact of weight management interventions on eating disorder risk.
Emotional and intuitive eating are associated with obesity. In the present study, it was aimed to evaluate the relationship between intuitive eating and emotional eating behaviours in adults with anthropometric measurements of obesity-related disease risk and gender. Body weight, body mass index (BMI), waist, hip and neck circumferences were taken. Emotional Eater Questionnaire and Intuitive Eating Scale-2 were used for the assessment of eating behaviour. A total of 3742 adult individuals (56⋅8 % (n 2125) female and (n 1617) male) were participated voluntarily. The total score and subscales of EEQ were higher in females than males (P < 0⋅001). The scores of the IES-2 subscales and the total score were higher in males than females (P < 0⋅05). In metabolic risk classification according to waist and neck circumference, EEQ scale scores (except type of food) were higher in the metabolic risk group, while IES-2 (except body-food congruence in neck circumference) scores were higher in the non-risk group (P < 0⋅05). While there was a positive correlation between EEQ and body weight, BMI, waist circumference, waist-height ratio, a negative correlation was found between age and waist-hip ratio. There was a negative correlation between IES-2 and body weight, BMI, waist-height ratio, waist-hip ratio. In addition, a negative correlation was found between IES-2 and EEQ. Intuitive eating and emotional eating differ by gender. Anthropometric measures and metabolic disease risk is associated with emotional eating and intuitive eating. Interventions to increase intuitive and decreasing emotional eating behaviour can be effective in preventing both obesity and obesity-related diseases.
This chapter examines the impacts of consuming a Western-style diet (WS-diet), rich in saturated fat, sugar and salt. Animal and human data convincingly show that a WS-diet causes hippocampal and prefrontal cortical impairment. Determining which component of a WS-diet is responsible is not currently clear. Several mechanisms may underpin these adverse effects on the brain: (1) reductions in neurotrophic factors; (2) neuroinflammation; (3) oxidative stress; (4) increased stress responsivity; (5) selective vulnerabilities in the hippocampal blood-brain barrier; and (6) changes to gut microbiota. The last one is intriguing as gut microbiota changes may impair the gut endothelial barrier allowing gut material to leak into the bloodstream, subsequently affecting the brain. Eating a WS-diet has also been linked to poorer mental health (anxiety/depression), it may exacerbate multiple sclerosis, and increased risk for Alzheimer’s and Parkinson’s disease. Finally, obesity may be a consequence of these adverse neural changes, leading to appetitive dysregulation and overeating.
Making healthy food choices is crucial for health promotion and disease prevention. While there are an increasing number of technology-assisted interventions to promote healthy food choices, the underlying mechanism by which consumption behaviours and weight status change remains unclear. Our scoping review and meta-analysis of seventeen studies represents 3988 individuals with mean ages ranging from 19·2 to 54·2 years and mean BMI ranging from 24·5 kg/m2 to 35·6 kg/m2. Six main outcomes were identified namely weight, total calories, vegetables, fruits, healthy food, and fats and other food groups including sugar-sweetened beverages, saturated fats, snacks, wholegrains, Na, proteins, fibre, cholesterol, dairy products, carbohydrates, and takeout meals. Technology-assisted interventions were effective for weight loss (g = –0·29; 95 % CI –0·54, −0·04; I2 = 65·7 %, t = –2·83, P = 0·03) but not for promoting healthy food choices. This highlights the complexity in creating effective interactive technology-assisted interventions and understanding its mechanisms of influence and change. We also identified that there needs to be greater application of theory to inform the development of technology-assisted interventions in this area as new and improved interventions are being developed.
Life expectancy has increased exponentially in the last century accompanied by disability, poor quality of life, and all-cause mortality in older age due to the high prevalence of obesity and physical inactivity in older people. Biologically, the aging process reduces the cell’s metabolic and functional efficiency, and disrupts the cell’s anabolic and catabolic homeostasis, predisposing older people to many dysfunctional conditions such as cardiovascular disease, neurodegenerative disorders, cancer, and diabetes. In the immune system, aging also alters cells' metabolic and functional efficiency, a process known as ‘immunosenescence’, where cells become more broadly inflammatory and their functionality is altered. Notably, autophagy, the conserved and important cellular process that maintains the cell’s efficiency and functional homeostasis may protect the immune system from age-associated dysfunctional changes by regulating cell death in activated CD4+ T cells. This regulatory process increases the delivery of the dysfunctional cytoplasmic material to lysosomal degradation while increasing cytokine production, proliferation, and differentiation of CD4+ T cell-mediated immune responses. Poor proliferation and diminished responsiveness to cytokines appear to be ubiquitous features of aged T cells and may explain the delayed peak in T cell expansion and cytotoxic activity commonly observed in the ‘immunosenescence’ phenotype in the elderly. On the other hand, physical exercise stimulates the expression of crucial nutrient sensors and inhibits the mechanistic target of the rapamycin (mTOR) signaling cascade which increases autophagic activity in cells. Therefore, in this perspective review, we will first contextualize the overall view of the autophagy process and then, we will discuss how body adiposity and physical fitness may counteract autophagy in naïve CD4+ T cells in aging.
While there is an increasing prevalence of dieting in the overall population, weight loss (WL) practices could be a risk factor for weight gain (WG) in normal-weight (NW) individuals. The aim of the present work was to systematically review all the studies implicating diet restriction and body weight (BW) evolution in NW people. The literature search was registered in PROSPERO (CRD42021281442) and was performed in three databases from April 2021 to June 2022 for articles involving healthy NW adults. From a total of 1487 records initially identified, eighteen were selected in the systematic review. Of the eight dieting interventional studies, only one found a higher BW after weight recovery, but 75 % of them highlighted metabolic adaptations in response to WL favouring weight regain and persisting during/after BW recovery. Eight of the ten observational studies showed a relationship between dieting and major later WG, while the meta-analysis of observational studies results indicated that ‘dieters’ have a higher BW than ‘non-dieters’. However, considering the high methodological heterogeneity and the publication bias of the studies, this result should be taken with caution. Moreover, the term ‘diet’ was poorly described, and we observed a large heterogeneity of the methods used to assess dieting status. Present results suggest that dieting could be a major risk factor for WG in the long term in NW individuals. There is, however, a real need for prospective randomised controlled studies, specifically assessing the relationship between WL induced by diet and subsequent weight in this population.
Automated visual anthropometrics produced by mobile applications are accessible and cost-effective with the potential to assess clinically relevant anthropometrics without a trained technician present. Thus, the aim of this study was to evaluate the precision and agreement of smartphone-based automated anthropometrics against reference tape measurements. Waist and hip circumference (WC; HC), waist-to-hip ratio (WHR), and waist-to-height ratio (W:HT), were collected from 115 participants (69 F) using a tape measure and two smartphone applications (MeThreeSixty®, myBVI®) across multiple smartphone types. Precision metrics were used to assess test-retest precision of the automated measures. Agreement between the circumferences produced by each mobile application and the reference were assessed using equivalence testing and other validity metrics. All mobile applications across smartphone types produced reliable estimates for each variable with ICCs ≥0.93 (all p<0.001) and RMS-%CV between 0.5%-2.5%. PE for WC and HC were between 0.5cm-1.9cm. WC, HC, and W:HT estimates produced by each mobile application demonstrated equivalence with the reference tape measurements using 5% equivalence regions. Mean differences via paired t-tests were significant for all variables across each mobile application (all p<0.050) showing slight underestimation for WC and slight overestimation for HC which resulted in a lack of equivalence for WHR compared to the reference tape measure. Overall, the results of our study support the use of WC and HC estimates produced from automated mobile applications, but also demonstrates the importance of accurate automation for WC and HC estimates given their influence on other anthropometric assessments and clinical health markers.
Attention-deficit/hyperactivity disorder (ADHD) and obesity are positively associated, with increasing evidence that they share genetic risk factors. Our aim was to examine whether these findings apply to both types of ADHD symptoms for female and male adolescents. We used data from 791 girl and 735 boy twins ages 16−17 years to examine sex-specific phenotypic correlations between the presence of ADHD symptoms and overweight/obese status. For correlations exceeding .20, we then fit bivariate twin models to estimate the genetic and environmental correlations between the presence of ADHD symptoms and overweight/obese status. ADHD symptoms and height/weight were parent- and self-reported, respectively. Phenotypic correlations were .30 (girls) and .08 (boys) for inattention and overweight/obese status and .23 (girls) and .14 (boys) for hyperactivity/impulsivity and overweight/obese status. In girls, both types of ADHD symptoms and overweight/obese status were highly heritable, with unique environmental effects comprising the remaining variance. Furthermore, shared genetic effects explained most of the phenotypic correlations in girls. Results suggest that the positive association of both types of ADHD symptoms with obesity may be stronger in girls than boys. Further, in girls, these associations may stem primarily from shared genetic factors.
It is unknown if fibre intake differs across diabetes status in USA adults and is associated with glycaemic outcomes. This cross-sectional analysis utilised National Health and Nutrition Examination Survey cycles 2013–2018 data to estimate usual total dietary fibre intake in USA adults and across diabetes status (no diabetes, prediabetes and type II diabetes (T2D)). Associations among dietary fibre intake and glycaemic outcomes were also reported across groups. Adults (≥ 19 years) with at least one dietary recall were included. Diabetes status was determined from self-report data and measured HbA1c. Independent samples t tests were used to compare mean (se) intake across sub-populations. 14 640 adults (51·3 % female) with 26·4 % and 17·4 % classified as having prediabetes and T2D, respectively. Adults with T2D reported greater mean (se) dietary fibre intake compared with no T2D for females (9·5 (0·13) v. 8·7 (0·11) g/1000 kcal/d and males (8·5 (0·12) v. 7·7 (0·11) g/1000 kcal/d; P < 0·01)). However, only 4·2 (0·50)% and 8·1 (0·90)% of males and females with T2D, respectively, met the adequate intake for fibre. Fibre intake was associated with lower insulin (β = −0·80, P < 0·01), serum glucose (β = −1·35, P < 0·01) and Homeostatic Model Assessment for Insulin Resistance (β = −0·22, P < 0·01) in adults without diabetes, and no relationships in adults with prediabetes or T2D were found. Although dietary fibre intake was highest among adults with T2D, intake was suboptimal across all groups. In adults without diabetes, dietary fibre intake was associated with improved glycaemic outcomes and insulin resistance; however, these associations were attenuated by anthropometric and lifestyle covariates.
Forty-eight budgerigars (Melopsittacus undulatus) were pairwise housed in small (80 × 40 × 50 cm) and large (160 × 40 × 50 cm) (length × breadth × height) boxes, as well as in 2.0 × 1.0 × 2.0 m aviaries. All boxes and aviaries had two or three (aviaries) perches and food was offered on the bottom. The body masses of female budgerigars increased significantly when they were housed in boxes instead of aviaries. The size of the box did not influence body mass. The frequency of flying was adjusted to the size of the box as both males and females flew approximately twice as often from perch to perch in a small box than in a large box of double length. Flying behaviour differed significantly between large and small boxes and aviaries. The ratio of invariantly flying from perch to perch to all flying events increased from aviaries < large boxes < small boxes. About 75% of all flying events in small boxes consisted of flying from perch to perch. Females in boxes spent more time on the bottom where the food was placed than females in aviaries. Both the significant body mass gain in female budgerigars, as well as the invariant, stereotypic flying movements, indicated reduced welfare in budgerigars housed in boxes, compared with those in aviaries. Providing a large box did not prevent body mass gain, but did increase the variation in flying patterns. Under long-term housing conditions, boxes could lead to at least two serious welfare problems; obesity and stereotypic behaviour, and should be avoided for budgerigars. Therefore, aviary housing should be chosen wherever possible.
Non-alcoholic fatty liver disease (NAFLD) represents an excessive fat accumulation within the liver, usually associated with excess body weight. A liver biopsy is the gold standard for diagnosis, but it is inapplicable in population-based studies. In large populations, non-invasive methods could be used, which may also serve to identify potential protective factors. We aimed to (a) estimate NAFLD prevalence in the adult population in Chile by using non-invasive methods and (b) determine the association between the presence of NAFLD and lifestyle habits. The National Health Survey of Chile 2016–2017 was analysed. We included individuals aged 21–75 years, without infectious diseases nor risky alcohol consumption. NAFLD was detected by either fatty liver index (FLI; considers circulating TAG, circulating γ-glutamyl-transferase, BMI and waist circumference), lipid accumulation product (LAP; considers sex, circulating TAG and waist circumference) or their combination. Lifestyle habits were determined by questionnaires. We included 2774 participants, representative of 10 599 094 (9 831 644, 11 366 544) adults in Chile. NAFLD prevalence (95 % CI) was 39·4 % (36·2, 42·8) by FLI, 27·2 % (24·2, 30·4) by LAP and 23·5 % (20·7, 26·5) by their combination. The prevalence progressively increased with increasing BMI. Of note, less smoking and more moderate-vigorous physical activity and whole-grain consumption were associated with lower odds of having NAFLD, independently of BMI. At least one out of four adults in Chile is afflicted with NAFLD. Health promotion strategies focused on controlling excess body weight and promoting specific lifestyle habits are urgently required.