Functional organization of motor cortex of adult macaque monkeys is altered by sensory loss in infancy

When somatosensory cortex (S1) is deprived of some of its inputs after section of ascending afferents in the dorsal columns of the spinal cord, it reorganizes to overrepresent the surviving inputs. As somatosensory cortex provides guiding sensory information to motor cortex, such sensory loss and representational reorganization could affect the development of the motor map in primary motor cortex (M1), especially if the sensory loss occurs early in development. To address this possibility, the dorsal columns of the spinal cord were sectioned between cervical levels (C3–5) 3–12 days after birth in five macaque monkeys. After 3–5 years of maturation (young adults), we determined how movements were represented in M1 contralateral to the lesion by using microelectrodes to electrically stimulate sites in M1 to evoke movements. Although the details of the motor maps in these five monkeys varied, the forelimb motor maps were abnormal. The representations of digit movements were reduced and abnormally arranged. Current levels for evoking movements from the forelimb region of M1 were in the normal range, but the lowest mean stimulation thresholds were for wrist or elbow instead of digit movements. Incomplete lesions and bilateral lesions produced fewer abnormalities. The results suggest that the development of normal motor cortex maps in M1 depends on sensory feedback from somatosensory maps.     

Argument for a non‐linear relationship between severity of human obesity and dopaminergic tone

Alterations in the dopaminergic system have been implicated in both animal and human obesity. However, to date, a comprehensive model on the nature and functional relevance of this relationship is missing. In particular, human data remain equivocal in that seemingly inconsistent reports exist of positive, negative or even no relationships between dopamine D2/D3 receptor availability in the striatum and measures of obesity. Further, data on receptor availability have been commonly interpreted as reflecting receptor density, despite the possibility of an alternative interpretation, namely alterations in the basal levels of endogenous dopaminergic tone. Here, we provide a unifying framework that is able to explain the seemingly contradictory findings and offer an alternative and novel perspective on existing data. In particular, we suggest (i) a quadratic relationship between alterations in the dopaminergic system and degree of obesity, and (ii) that the observed alterations are driven by shifts in the balance between general dopaminergic tone and phasic dopaminergic signalling. The proposed model consistently integrates human data on molecular and behavioural characteristics of overweight and obesity. Further, the model provides a mechanistic framework accounting not only for the consistent observation of altered (food) reward–responsivity but also for the differences in reinforcement learning, decision‐making behaviour and cognitive performance associated with measures of obesity.     

Utility values for childhood obesity interventions: a systematic review and meta‐analysis of the evidence for use in economic evaluation

Rigorous estimates of preference‐based utilities are important inputs into economic evaluations of childhood obesity interventions, yet no published review currently exists examining utility by weight status in paediatric populations. A comprehensive systematic literature review and meta‐analysis was therefore undertaken, pooling data on preference‐based health state utilities by weight status in children using a random‐effects model. Tests for heterogeneity were performed, and publication bias was assessed. Of 3,434 potentially relevant studies identified, 11 met our eligibility criteria. Estimates of Cohen's d statistic suggested a small effect of weight status on preference‐based utilities. Mean utility values were estimated as 0.85 (95% uncertainty interval [UI] 0.84–0.87), 0.83 (95% UI 0.81–0.85), 0.82 (95% UI 0.79–0.84) and 0.83 (95% UI 0.80–0.86) for healthy weight, overweight, obese and overweight/obese states, respectively. Meta‐analysis of studies reporting utility values for both healthy weight and overweight/obese participants found a statistically significant weighted mean difference (0.015, 95% UI 0.003–0.026). A small but statistically significant difference was also estimated between healthy weight and overweight participants (0.011, 95% UI 0.004–0.018). Study findings suggest that paediatric‐specific benefits of obesity interventions may not be well reflected by available utility measures, potentially underestimating cost‐effectiveness if weight loss in childhood/adolescence improves health or well‐being.     

Immunocytochemical localization of androgen receptors in brains of developing and adult male rhesus monkeys

We localized immunoreactive androgen receptors in the central nervous system (CNS) of fetal and adult male rhesus macaques by immunocytochemisty using an affinity-purified polyclonal antibody to the first 21 amino acids of the human androgen receptor (AR). This antibody caused a shift in the mobility of AR-bound ³H-DHT on a sucrose gradient and recognized a protein of approx 116 kDa on Western blot. Other criteria for specificity are presented. We localized AR in the diencephalon of male rhesus monkey fetuses. Immunoreactive neurons were found in the medial hypothalamic area and the ventromedial nucleus of the hypothalamus on days 47, 61, and 124 of gestation. At 124 d of gestation, AR immunoreactivity was also found in the arcuate nucleus. AR immunostaining was not found in other diencephalic structures in fetal life, including the preoptic area. In the adult monkey, neurons in ventromedial, dorsomedial, and arcuate nuclei of the hypothalamus; cortical, medial, and accessory basal nuclei of the amygdala; and regions of the hippocampus and the anterior pituitary gland contained immunoreactive AR. These data indicate that AR is found in specific areas of the CNS early in fetal development, but they also appear in other brain areas as the fetus grows. At 124 d of gestation (term, 167 d), the hypothalamic location of immunoreactive AR is similar to the adult.     

Behavioral and neural correlates of increased self-control in the absence of increased willpower

People often exert willpower to choose a more valuable delayed reward over a less valuable immediate reward, but using willpower is taxing and frequently fails. In this research, we demonstrate the ability to enhance self-control (i.e., forgoing smaller immediate rewards in favor of larger delayed rewards) without exerting additional willpower. Using behavioral and neuroimaging data, we show that a reframing of rewards (i) reduced the subjective value of smaller immediate rewards relative to larger delayed rewards, (ii) increased the likelihood of choosing the larger delayed rewards when choosing between two real monetary rewards, (iii) reduced the brain reward responses to immediate rewards in the dorsal and ventral striatum, and (iv) reduced brain activity in the dorsolateral prefrontal cortex (a correlate of willpower) when participants chose the same larger later rewards across the two choice frames. We conclude that reframing can promote self-control while avoiding the need for additional willpower expenditure.Self-control is highly desirable and correlates with beneficial outcomes such as financial stability (1, 2), academic achievement (3, 4), social success (5, 6), and healthy living (1, 7). Many cognitive and behavioral strategies may be used to achieve self-control (8). We contrast two broad self-control strategies that affect how people respond to an immediately available, tempting reward. First, people may attempt to directly modulate their behavior through effortful willpower exertion, to select delayed rewards despite the presence of distracters or temptations. Alternatively, the perception of temptations may be altered so as to promote self-control. Exerting willpower is taxing and hence often of limited efficacy (9). By contrast, changing how outcomes are perceived and valued has the benefit of more automatically shaping behavior and may prove a superior target for interventions and long-term behavioral change.Recent findings support the plausibility of independently assessing changes in reward valuation and changes in willpower exertion because brain systems underlying reward valuation are distinct from those associated with willpower exertion (10, 11). More specifically, studies of intertemporal choice link valuation processes to the ventromedial prefrontal cortex and striatum (10, 12–14), whereas willpower exertion is associated with the dorsolateral prefrontal cortex (dlPFC) (10, 11, 15). However, no study has demonstrated that self-control can be engaged in a way that influences monetary choice behavior in an intertemporal choice context without the exertion of additional willpower.Our goal was to demonstrate that the ability to make far-sighted choices may be enhanced without requiring the use of additional willpower, by altering how rewards are perceived and valued. We triangulated the process of altering reward perception and valuation by obtaining data through self-report (subjective reward valuation), behavioral measures (monetary choices), and neuroimaging (neural activity underlying reward valuation versus willpower exertion). In doing so, we capitalized on the hidden-zero effect, a subtle cognitive framing manipulation (16) that increases selection of larger delayed monetary rewards over smaller immediate monetary rewards.In our paradigm, instead of presenting choices in a traditional hidden-zero format (e.g., “Would you prefer [A] $5 today OR [B] $10 in a month?”), choices are presented in an explicit-zero format, which references the nonreward consequences of each choice (e.g., “Would you prefer [A] $5 today and $0 in a month OR [B] $0 today and $10 in a month?”). Including future outcomes in all choice options has been argued to reduce the attentional bias toward immediate rewards that contributes to impulsive behavior (17).Of course, this change in attention may influence reward evaluation (by making the delayed reward more valued relative to the immediate one), or it may prompt greater effortful exertion of willpower. In terms of the latter possibility, willpower has been argued to arise from conflict in the decision process (11), and increased attention to future rewards (or nonrewards) may enhance conflict with a desire for immediate gratification. In this case, an effortful process might be triggered. We tested these two alternatives for the basis of the hidden-zero effect. In study 1, we examined the effect of the explicit-zero framing on participants’ subjective valuation of immediate and delayed rewards and linked this effect to monetary choice. In study 2, we used functional magnetic resonance imaging (fMRI) to identify the neural effects of reframing on reward valuation, monetary choice behavior, and willpower exertion.     

A systematic review of economic evidence for community-based obesity prevention interventions in children

Multicomponent community-based obesity prevention interventions that engage multiple sectors have shown promise in preventing obesity in childhood; however, economic evaluations of such interventions are limited. This systematic review explores the methods used and summarizes current evidence of costs and cost-effectiveness of complex obesity prevention interventions. A systematic search was conducted using 12 academic databases and grey literature from 2006 to April 2022. Studies were included if they reported methods of costing and/or economic evaluation of multicomponent, multisectoral, and community-wide obesity prevention interventions. Results were reported narratively based on the Consolidated Health Economic Evaluation Reporting Standards. Seventeen studies were included, reporting costing or economic evaluation of 13 different interventions. Five interventions reported full economic evaluations, five interventions reported economic evaluation protocols, two interventions reported cost analysis, and one intervention reported a costing protocol. Five studies conducted cost-utility analysis, three of which were cost-effective. One study reported a cost-saving return-on-investment ratio. The economic evidence for complex obesity prevention interventions is limited and therefore inconclusive. Challenges include accurate tracking of costs for interventions with multiple actors, and the limited incorporation of broader benefits into economic evaluation. Further methodological development is needed to find appropriate pragmatic methods to evaluate complex obesity prevention interventions.     

Inverse relationship between LDL cholesterol and PCSK9 plasma levels in dyslipidemic cynomolgus monkeys: Effects of LDL lowering by ezetimibe in the absence of statins

Objectives

To assess the lipid-lowering efficacy of ezetimibe in dyslipidemic cynomolgus monkeys comparing two dosing methods, and to evaluate PCSK9 plasma levels during dyslipidemia induction by feeding a high-fat/high-cholesterol diet (HFD), ezetimibe (Zetia^®, Ezetrol^®) treatment, ezetimibe washout, and HFD washout.

Methods and results

Twenty dyslipidemic cynomolgus monkeys on HFD for seven months (LDL cholesterol 100–400 mg/dL) were randomized into two groups and treated with ezetimibe for two weeks, either by oral gavage or by using food treats. The lipid-lowering effects of ezetimibe were identical between the two groups. After treatment, mean LDL cholesterol was decreased by 58% (174–72 mg/dL), total cholesterol by 42% (241–138 mg/dL), and PCSK9 levels were increased by 137% (147–314 ng/mL). PCSK9 levels on regular diet before and after HFD were also inversely correlated to LDL cholesterol.

Conclusions

In a cynomolgus dyslipidemia model, PCSK9 levels are inversely correlated with LDL cholesterol in the absence of statin treatment, regardless whether lipid changes are modulated by diet or ezetimibe treatment.     

The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review

Leptin and ghrelin are two hormones that have been recognized to have a major influence on energy balance. Leptin is a mediator of long-term regulation of energy balance, suppressing food intake and thereby inducing weight loss. Ghrelin on the other hand is a fast-acting hormone, seemingly playing a role in meal initiation. As a growing number of people suffer from obesity, understanding the mechanisms by which various hormones and neurotransmitters have influence on energy balance has been a subject of intensive research. In obese subjects the circulating level of the anorexigenic hormone leptin is increased, whereas surprisingly, the level of the orexigenic hormone ghrelin is decreased. It is now established that obese patients are leptin-resistant. However, the manner in which both the leptin and ghrelin systems contribute to the development or maintenance of obesity is as yet not clear. The purpose of this review is to provide background information on the leptin and ghrelin hormones, their role in food intake and body weight in humans, and their mechanism of action. Possible abnormalities in the leptin and ghrelin systems that may contribute to the development of obesity will be mentioned. In addition, the potentials of leptin and ghrelin as drug targets will be discussed. Finally, the influence of the diet on leptin and ghrelin secretion and functioning will be described.     

Attentional biases for food cues in overweight and individuals with obesity: a systematic review of the literature

Obesity rates have increased dramatically in recent decades, and it has proven difficult to treat. An attentional bias towards food cues may be implicated in the aetiology of obesity and influence cravings and food consumption. This review systematically investigated whether attentional biases to food cues exist in overweight/obese compared with healthy weight individuals. Electronic database were searched for relevant papers from inception to October 2014. Only studies reporting food‐related attentional bias between either overweight (body mass index [BMI] 25.0–29.9 kg m^?2) or obese (BMI ≥ 30) participants and healthy weight participants (BMI 18.5–24.9) were included. The findings of 19 studies were reported in this review. Results of the literature are suggestive of differences in attentional bias, with all but four studies supporting the notion of enhanced reactivity to food stimuli in overweight individuals and individuals with obesity. This support for attentional bias was observed primarily in studies that employed psychophysiological techniques (i.e. electroencephalogram, eye‐tracking and functional magnetic resonance imaging). Despite the heterogeneous methodology within the featured studies, all measures of attentional bias demonstrated altered cue‐reactivity in individuals with obesity. Considering the theorized implications of attentional biases on obesity pathology, researchers are encouraged to replicate flagship studies to strengthen these inferences.     

Pulmonary delivery of peptide YY for food intake suppression and reduced body weight gain in rats

Aims: Peptide YY (PYY) is an endogenous anorectic gut‐secreted peptide that has been shown to suppress appetite in animals and humans, when given by injection. This study tested if needle‐free pulmonary delivery of PYY enables food intake suppression and reduced body weight gain in rats. The PYY pharmacokinetics and effects on brain neuropeptide levels were also examined. Methods: Rats received single or once‐daily 7‐day pulmonary administration of saline or PYYs. Food intake and body weight gain were monitored to study the effects of different doses (0.08–0.90 mg/kg) of PYY3‐36, PYY1‐36 and PYY13‐36. Plasma PYY pharmacokinetics were determined via enzyme‐linked immunosorbent assay. Changes in orexigenic neuropeptide Y (NPY) and c‐Fos protein levels in the hypothalamus arcuate nucleus (ARC) were measured by immunofluorescence microscopy. Results: PYY3‐36 caused dose‐dependent and 4‐ to 6‐h food intake suppression following pulmonary delivery. At 0.80 mg/kg, the effect was significant with 35.1 ± 5.7 and 19.7 ± 4.2% suppression at 4 and 6 h, respectively. Repeated administration for 7 days reduced cumulative body weight gain by 39.4 ± 11.0%. PYY1‐36, but not PYY13‐36, was equipotent to PYY3‐36 in food intake suppression. The plasma PYY concentration reached its peak at 10 min following pulmonary delivery with 12–14% of bioavailability. Increased c‐Fos and reduced NPY expressions were observed in the hypothalamus ARC, consistent with the magnitude of food intake suppression by each of the PYYs. Conclusions: Pulmonary delivery of PYY enabled significant 4‐ to 6‐h food intake suppression via 12–14% of lung absorption and hypothalamic ARC interaction, leading to reduced body weight gain in rats.     

Impact of food support on food security and body weight among HIV antiretroviral therapy recipients in Honduras: a pilot intervention trial

Optimal strategies to improve food security and nutrition for people living with HIV (PLHIV) may differ in settings where overweight and obesity are prevalent and cardiovascular disease risk is a concern. However, no studies among PLHIV have investigated the impact of food support on nutritional outcomes in these settings. We therefore assessed the effect of food support on food insecurity and body weight in a population of PLHIV with high prevalence of overweight and obesity. We implemented a pilot intervention trial in four government-run HIV clinics in Honduras. The trial tested the effect of a monthly household food ration plus nutrition education (n = 203), compared to nutrition education alone (n = 197), over 12 months. Participants were clinic patients receiving antiretroviral therapy (ART). Assessments were obtained at baseline, 6 and 12 months. Primary outcomes for this analysis were food security, using the validated Latin American and Caribbean Food Security Scale and body weight (kg). Thirty-one percent of participants were overweight (22%) or obese (8%) at baseline. At 6 months, the probability of severe food insecurity decreased by 48.3% (p < 0.01) in the food support group, compared to 11.6% in the education-only group (p < 0.01). Among overweight or obese participants, food support led to average weight gain of 1.13 kg (p < 0.01), while nutrition education alone was associated with average weight loss of 0.72 kg (p < 0.10). Nutrition education alone was associated with weight gain among underweight and normal weight participants. Household food support may improve food security but not necessarily nutritional status of ART recipients above and beyond nutrition education. Improving nutritional tailoring of food support and testing the impact of nutrition education should be prioritized for PLHIV in Latin America and similar settings.     

Supply and demand determine the market value of food providers in wild vervet monkeys

Animals neither negotiate verbally nor conclude binding contracts, but nevertheless regularly exchange goods and services without overt coercion and manage to arrive at agreements over exchange rates. Biological market theory predicts that such exchange rates fluctuate according to the law of supply and demand. Previous studies showed that primates pay more when commodities become scarcer: subordinates groomed dominants longer before being tolerated at food sites in periods of shortage; females groomed mothers longer before obtaining permission to handle their infants when there were fewer newborns and males groomed fertile females longer before obtaining their compliance when fewer such females were present. We further substantiated these results by conducting a 2-step experiment in 2 groups of free-ranging vervet monkeys in the Loskop Dam Nature Reserve, South Africa. We first allowed a single low-ranking female to repeatedly provide food to her entire group by triggering the opening of a container and measured grooming bouts involving this female in the hour after she made the reward available. We then measured the shifts in grooming patterns after we added a second food container that could be opened by another low-ranking female, the second provider. All 4 providers received more grooming, relative to the amount of grooming they provided themselves. As biological market theory predicts, the initial gain of first providers was partially lost again after the introduction of a second provider in both groups. We conclude that grooming was fine-tuned to changes in the value of these females as social partners.     

Changes in food intake during menstrual cycles and pregnancy of normal and diabetic rhesus monkeys

Summary Food intake of control and streptozotocin-diabetic rhesus monkeys was measured during menstrual cycles and pregnancy. Intake of control monkeys was lower at the time of ovulation than during other phases of the menstrual cycle. Intake of control monkeys was also low during most of pregnancy, but this was accompanied by normal fetal growth and net maternal weight gain. Diabetic monkeys ate more than controls in all conditions and their intake did not vary reliably according to reproductive status. It is suggested that (1) oestrogen normally inhibits food intake during menstrual cycles and pregnancy, (2) food energy is utilized more efficiently during pregnancy than during non-pregnant states, and (3) the influence of oestrogen on food intake is either attenuated by insulinopenia or is obscured by the hyperphagia typically exhibited by the diabetic monkeys.     

Interactions of amylinergic and melanocortinergic systems in the control of food intake and body weight in rodents

Aims: Amylinergic and melanocortinergic systems have each been implicated in energy balance regulation. We examined the interactive effects of both systems using gene knockout and pharmacological approaches. Methods: Acute food consumption was measured in overnight fasted male wild‐type (WT) and melanocortin‐4 receptor (MC‐4R) deficient rats and in male and female WT and amylin knockout mice (AmyKO). Changes in food intake, body weight and composition in male WT and MC‐4R deficient rats and in male diet‐induced obese (DIO) rats. Pharmacological treatments included either rat amylin, murine leptin and/or the MC‐4R agonist, Ac‐R[CEH‐dF‐RWC]‐amide. Results: Amylin (10 µg/kg, IP) decreased food intake in WT but not in MC‐4R deficient rats (30 and 60 min post‐injection). Ac‐R[CEH‐dF‐RWC]‐amide (100 µg/kg, IP) suppressed food intake similarly in male WT and AmyKO, but was ineffective in female AmyKO. Amylin (50 µg/kg/day for 28 days) and leptin (125 µg/kg/day) synergistically reduced food intake and body weight in WT and MC‐4R deficient rats to a similar extent. Amylin (100 µg/kg) combined with Ac‐R[CEH‐dF‐RWC]‐amide (100 µg/kg, IP) decreased acute food intake over 3 h to a greater extent than either agent alone in fasted mice. In DIO rats, additive anorexigenic, weight‐ and fat‐lowering effects were observed over 12 days with the combination of rat amylin (50 µg/kg/day) and Ac‐R[CEH‐dF‐RWC]‐amide (2.3 mg/kg, SC injected daily). Conclusions: Although amylin's acute anorexigenic effects are somewhat blunted in MC‐4R deficiency and those of MC‐4R agonism in amylin deficiency, these effects are surmountable with pharmacological administration lending therapeutic potential to combined amylin/melanocortin agonism for obesity.     

The role of diets, food, and nutrients in the prevention and control of hypertension and prehypertension

Hypertension is the leading risk factor for death worldwide, even surpassing tobacco use, high blood glucose, high blood cholesterol, and obesity. Globally, the estimated prevalence of hypertension is nearly 1 billion persons with an annual mortality of almost 7.5 million deaths. In the United States, hypertension affects an estimated 65 million Americans, and is the leading risk-factor cause of death in women and only second to tobacco use as a contributory cause of death in men. Multiple sources of data from prospective observational, cohort, and randomized controlled clinical trials show that hypertension and its complications are highly preventable when the raised blood pressure is prevented, or treated and controlled. To promote positive behavior change and create a broader impact on public health, it has become necessary to leverage multilevel stakeholders such as all health care providers, researchers, policy makers, schools, the food industry, and the general public to drive policy changes and future innovation from research and development endeavors, and to emphasize the importance of diet-related lifestyle modifications to effectively prevent and control hypertension and prehypertension.     

南京市秦淮区老年居民食物和营养素摄入特点分析

目的了解南京市秦淮区老年居民膳食营养素摄取特点,为建议居民合理膳食及开展营养宣教提供依据。方法用连续3d24h膳食回顾法对291名居民进行膳食调查,并将老年与青年、中年居民的膳食营养素摄取状况进行比较分析。结果与青年、中年居民相比,老年男性居民的畜肉类、糕点类食品摄取量明显较低,而奶类、糖类摄取量较高,营养素摄取量无明显差异;能量、锌摄取量达到RNI要求的比例明显高于青年、中年男性。老年女性居民的畜肉、禽肉、蛋类食品摄取量明显较低,而油类摄取量较高。蛋白质、烟酸、硒、胆固醇摄取量明显较低,维生素B2、硒、烟酸摄取量达到RNI要求的比例明显较低,胆固醇摄取量超过300mg／d者的比例也较低。男女性老年居民水产类食品摄取量均较低。结论老年男性居民的牛奶摄取量多,但畜肉类食品摄取量少,脂肪、硒摄取量略低,而维生素A、钙的摄取量略高。老年女性居民的动物性食品摄取量较少,而油类食品摄取量较多,胆固醇摄取量明显减少,维生素B2、烟酸、硒的摄取量达到RNIs要求的比例明显较低。     

Prevalence of overweight in the Seychelles: 15 year trends and association with socio‐economic status

We assessed the 15‐year trends in the distribution of body mass index (BMI) and the prevalence of overweight in the Seychelles (Indian Ocean, African Region) and the relationship with socio‐economic status (SES). Three population‐based examination surveys were conducted in 1989, 1994 and 2004. Occupation was categorized as ‘labourer’, ‘intermediate’ or ‘professional’. Education was also assessed in 1994 and 2004. Between 1989 and 2004, mean BMI increased markedly in all sex and age categories (overall: 0.16 kg m^?2 per calendar year, which corresponds to 0.46 kg per calendar year). The prevalence of overweight (including obesity, BMI ≥ 25 kg m^?2) increased from 29% to 52% in men and from 50% to 67% in women. The prevalence of obesity (BMI ≥ 30 kg m^?2) increased from 4% to 15% in men and from 23% to 34% in women. Overweight was associated inversely with occupation in women and directly in men in all surveys. In multivariate analysis, overweight was associated similarly (direction and magnitude) to occupation and education. In conclusion, the increasing prevalence of overweight and obesity over time in all age, sex and SES categories suggests large‐scale changes in societal obesogenic factors. The sex‐specific association of SES with overweight suggests that prevention measures should be tailored accordingly.     

An overview of obesity mechanisms in humans: Endocrine regulation of food intake,eating behaviour and common determinants of body weight

Obesity is one of the biggest health challenges of the 21st century, already affecting close to 700 million people worldwide, debilitating and shortening lives and costing billions of pounds in healthcare costs and loss of workability. Body weight homeostasis relies on complex biological mechanisms and the development of obesity occurs on a background of genetic susceptibility and an environment promoting increased caloric intake and reduced physical activity. The pathophysiology of common obesity links neuro-endocrine and metabolic disturbances with behavioural changes, genetics, epigenetics and cultural habits. Also, specific causes of obesity exist, including monogenetic diseases and iatrogenic causes. In this review, we provide an overview of obesity mechanisms in humans with a focus on energy homeostasis, endocrine regulation of food intake and eating behavior, as well as the most common specific causes of obesity.     

Framing obesity in UK policy from the Blair years, 1997–2015: the persistence of individualistic approaches despite overwhelming evidence of societal and economic factors,and the need for collective responsibility

Since 1997, and despite several political changes, obesity policy in the UK has overwhelmingly framed obesity as a problem of individual responsibility. Reports, policies and interventions have emphasized that it is the responsibility of individual consumers to make personal changes to reduce obesity. The Foresight Report ‘Tackling Obesities: Future Choices’ (2007) attempted to reframe obesity as a complex problem that required multiple sites of intervention well beyond the range of personal responsibility. This framing formed the basis for policy and coincided with increasing acknowledgement of the complex nature of obesity in obesity research. Yet policy and interventions developed following Foresight, such as the Change4Life social marketing campaign, targeted individual consumer behaviour. With the Conservative‐Liberal Democrat government of 2011, intervention shifted to corporate and individual responsibility, making corporations voluntarily responsible for motivating individual consumers to change. This article examines shifts in the framing of obesity from a problem of individual responsibility, towards collective responsibility, and back to the individual in UK government reports, policies and interventions between 1997 and 2015. We show that UK obesity policies reflect the landscape of policymakers, advisors, political pressures and values, as much as, if not more than, the landscape of evidence. The view that the individual should be the central site for obesity prevention and intervention has remained central to the political framing of population‐level obesity, despite strong evidence contrary to this. Power dynamics in obesity governance processes have remained unchallenged by the UK government, and individualistic framing of obesity policy continues to offer the path of least resistance. © 2016 World Obesity