Obesity

Objective: Posttraumatic stress disorder (PTSD) has been linked to reduced heart rate variability (HRV), which is in turn a risk factor for cardiovascular disease and death. Although hyperarousal and anxiety are thought to underlie this association, behavioral health risks, including smoking, alcohol dependence, obesity, and sleep disturbance, represent potential mechanisms linking PTSD and HRV. Methods: To test this hypothesis, short-term laboratory-based and 24-hour ambulatory measures of HRV were collected from 227 young adults (18Y39 years), 107 of whom were diagnosed as having PTSD. Latent variable modeling was used to assess the relationship of PTSD symptoms with HRV along with potential behavioral health mediators. Results: PTSD symptoms were associated with reduced HRV (A = j0.21, p = .002). However, this association was reduced in models that adjusted for cigarette consumption and history of alcohol dependence and was rendered nonsignificant in a model adjusting for sleep disturbance. Independent mediation effects were deemed significant via bootstrapping analysis. Together, the three behavioral health factors (cigarette consumption, history of alcohol dependence, and sleep disturbance) accounted for 94% of the shared variance between PTSD symptoms and HRV. Abdominal obesity was not a significant mediator. Conclusions: These results indicate that behavioral factorsVspecifically smoking, alcohol overuse, and sleep disturbanceVmediate the association between PTSD and HRV-based indices of autonomic nervous system dysregulation. Benefits from psychiatric and psychological interventions in PTSD may therefore be enhanced by including modification of health behaviors. Key words: posttraumatic stress disorder, heart rate variability, cigarette smoking, alcohol dependence, sleep disturbance. PTSD = posttraumatic stress disorder; HRV = heart rate variability; SNS = sympathetic nervous system; PNS = parasympathetic nervous system; CAPS = Clinician Administered PTSD Scale; DTS = Davidson Trauma Scale; MDD = major depressive disorder; SDNN = standard deviation of all normal R-R intervals; TR index = triangular index; LF power = low-frequency power; HF power = highfrequency power; RRSD = standard deviation of normal-to-normal R-R intervals; RMSEA= root mean square error of approximation; CFI = comparative fit index; SRMR = standardized root mean square residual; CI = confidence interval.

Background

Frequent consumption of excess amounts of sugar‐sweetened beverages (SSB) is a risk factor for obesity, type 2 diabetes, cardiovascular disease and dental caries. Environmental interventions, i.e. interventions that alter the physical or social environment in which individuals make beverage choices, have been advocated as a means to reduce the consumption of SSB.

Objectives

To assess the effects of environmental interventions (excluding taxation) on the consumption of sugar‐sweetened beverages and sugar‐sweetened milk, diet‐related anthropometric measures and health outcomes, and on any reported unintended consequences or adverse outcomes.

Search methods

We searched 11 general, specialist and regional databases from inception to 24 January 2018. We also searched trial registers, reference lists and citations, scanned websites of relevant organisations, and contacted study authors.

Selection criteria

We included studies on interventions implemented at an environmental level, reporting effects on direct or indirect measures of SSB intake, diet‐related anthropometric measures and health outcomes, or any reported adverse outcome. We included randomised controlled trials (RCTs), non‐randomised controlled trials (NRCTs), controlled before‐after (CBA) and interrupted‐time‐series (ITS) studies, implemented in real‐world settings with a combined length of intervention and follow‐up of at least 12 weeks and at least 20 individuals in each of the intervention and control groups. We excluded studies in which participants were administered SSB as part of clinical trials, and multicomponent interventions which did not report SSB‐specific outcome data. We excluded studies on the taxation of SSB, as these are the subject of a separate Cochrane Review.

Data collection and analysis

Two review authors independently screened studies for inclusion, extracted data and assessed the risks of bias of included studies. We classified interventions according to the NOURISHING framework, and synthesised results narratively and conducted meta‐analyses for two outcomes relating to two intervention types. We assessed our confidence in the certainty of effect estimates with the GRADE framework as very low, low, moderate or high, and presented ‘Summary of findings’ tables.

Main results

We identified 14,488 unique records, and assessed 1030 in full text for eligibility. We found 58 studies meeting our inclusion criteria, including 22 RCTs, 3 NRCTs, 14 CBA studies, and 19 ITS studies, with a total of 1,180,096 participants. The median length of follow‐up was 10 months. The studies included children, teenagers and adults, and were implemented in a variety of settings, including schools, retailing and food service establishments. We judged most studies to be at high or unclear risk of bias in at least one domain, and most studies used non‐randomised designs. The studies examine a broad range of interventions, and we present results for these separately.

Labelling interventions (8 studies): We found moderate‐certainty evidence that traffic‐light labelling is associated with decreasing sales of SSBs, and low‐certainty evidence that nutritional rating score labelling is associated with decreasing sales of SSBs. For menu‐board calorie labelling reported effects on SSB sales varied.

Nutrition standards in public institutions (16 studies): We found low‐certainty evidence that reduced availability of SSBs in schools is associated with decreased SSB consumption. We found very low‐certainty evidence that improved availability of drinking water in schools and school fruit programmes are associated with decreased SSB consumption. Reported associations between improved availability of drinking water in schools and student body weight varied.

Economic tools (7 studies): We found moderate‐certainty evidence that price increases on SSBs are associated with decreasing SSB sales. For price discounts on low‐calorie beverages reported effects on SSB sales varied.

Whole food supply interventions (3 studies): Reported associations between voluntary industry initiatives to improve the whole food supply and SSB sales varied.

Retail and food service interventions (7 studies): We found low‐certainty evidence that healthier default beverages in children’s menus in chain restaurants are associated with decreasing SSB sales, and moderate‐certainty evidence that in‐store promotion of healthier beverages in supermarkets is associated with decreasing SSB sales. We found very low‐certainty evidence that urban planning restrictions on new fast‐food restaurants and restrictions on the number of stores selling SSBs in remote communities are associated with decreasing SSB sales. Reported associations between promotion of healthier beverages in vending machines and SSB intake or sales varied.

Intersectoral approaches (8 studies): We found moderate‐certainty evidence that government food benefit programmes with restrictions on purchasing SSBs are associated with decreased SSB intake. For unrestricted food benefit programmes reported effects varied. We found moderate‐certainty evidence that multicomponent community campaigns focused on SSBs are associated with decreasing SSB sales. Reported associations between trade and investment liberalisation and SSB sales varied.

Home‐based interventions (7 studies): We found moderate‐certainty evidence that improved availability of low‐calorie beverages in the home environment is associated with decreased SSB intake, and high‐certainty evidence that it is associated with decreased body weight among adolescents with overweight or obesity and a high baseline consumption of SSBs.

Adverse outcomes reported by studies, which may occur in some circumstances, included negative effects on revenue, compensatory SSB consumption outside school when the availability of SSBs in schools is reduced, reduced milk intake, stakeholder discontent, and increased total energy content of grocery purchases with price discounts on low‐calorie beverages, among others. The certainty of evidence on adverse outcomes was low to very low for most outcomes.

We analysed interventions targeting sugar‐sweetened milk separately, and found low‐ to moderate‐certainty evidence that emoticon labelling and small prizes for the selection of healthier beverages in elementary school cafeterias are associated with decreased consumption of sugar‐sweetened milk. We found low‐certainty evidence that improved placement of plain milk in school cafeterias is not associated with decreasing sugar‐sweetened milk consumption.

Authors' conclusions

The evidence included in this review indicates that effective, scalable interventions addressing SSB consumption at a population level exist. Implementation should be accompanied by high‐quality evaluations using appropriate study designs, with a particular focus on the long‐term effects of approaches suitable for large‐scale implementation.

Wistar of the National Institute of Nutrition obese (WNIN/Ob) is a unique rat strain isolated and established at NIN, Hyderabad, India, in 1996, from its existing stock of Wistar rat colony (WNIN). This animal model exhibits all traits of metabolic syndrome and has a remarkably reduced lifespan (1.5 years as compared to 3 years in parental WNIN rats), albeit, the factors associated with premature aging are not well understood. Considering that oxidative stress and DNA damage are crucial players associated with senescence, we analyzed oxidative stress markers like lipid peroxidation and protein oxidation; DNA damage in terms of both single-stranded and double-stranded breaks and the activity of antioxidant enzymes: superoxide dismutase and catalase in brain regions of these animals. Our study revealed that the magnitude of oxidative stress and DNA damage in the neocortex and hippocampus of 3-month-old WNIN/Ob obese rats is as high as that seen in 15-month-old parental WNIN control rats. Concurrently, the antioxidant enzyme activity was significantly decreased. From these results, it can be concluded that increased oxidative stress-induced damage of macromolecules, probably due to reduced activity of antioxidant enzymes, is associated with premature aging in WNIN/Ob obese rats.

BLAAKAND THE NUGENOB CONSORTIUM. Impaired fat-induced thermogenesis in obese subjects: the NUGENOB study. Obesity. 2007;15: 653-663. Objectives: To study energy expenditure before and 3 hours after a high-fat load in a large cohort of obese subjects (n ϭ 701) and a lean reference group (n ϭ 113). Research Methods and Procedures: Subjects from seven European countries underwent a 1-day clinical study with a liquid test meal challenge containing 95% fat (energy con-tent was 50% of estimated resting energy expenditure). Fasting and 3-hour postprandial energy expenditures, as well as metabolites and hormones, were determined. Results: Obese subjects had a reduced postprandial energy expenditure after the high-fat load, independent of body composition, age, sex, research center, and resting energy expenditure, whereas within the obese group, thermogenesis increased again with increasing BMI category. Additionally, insulin resistance, habitual physical activity, postprandial plasma triacylglycerols, and insulin were all independently positively related to the postprandial energy expenditure. Resting energy expenditure, adjusted for fat-free mass, increased with degree of obesity, a difference that disappeared after adjustment for fat mass. Furthermore, insulin resistance, fasting plasma free fatty acids, and cortisol were positively associated, whereas fasting plasma leptin and insulin-like growth factor-1 were negatively associated, with resting energy expenditure. Discussion: The 3-hour fat-induced thermogenic response is reduced in obesity. It remains to be determined whether this blunted thermogenic response is a contributory factor or an adaptive response to the obese state. REE, resting energy expenditure; HOMA IR , homeostasis model assessment of insulin resistance; AU, arbitrary units; EI, energy intake; FFA, free fatty acid; IGF-1, insulin-like growth factor-1. Model 1 includes the indicated variables in addition to FM, FFM, and center. Model 2 includes the indicated variables in addition to Model 1. p Values of the multiple regression analysis are indicated in the right column.

This paper aimed to investigate which parents use which types of parenting control practices to manage their children's diets and to assess the impact of these practices on children's dietary patterns and their BMI. A cross-sectional survey of 518 parents with children aged 4-7 years was carried out in 18 primary schools across the South of England. Measures included aspects of parental control practices and the child's diet. Results showed that older parents with a lower BMI and who were stay at home parents used more ''snack overt control'', ''snack covert control'' and ''meal covert control'' and those with more education used more covert control strategies. In contrast, male, non-white parents with younger children used more ''pressure to eat''. In terms of the children's diet, the results showed links between parental and child demographics and aspects of unhealthy and healthy food intake. In addition, links were also found for parental control practices. For example, eating more unhealthy snacks was related to less covert control and more pressure to eat, eating fruit and vegetables was related to higher levels of both overt and covert control over meals and less pressure to eat and being neophobic was related to less covert control over meals and more pressure to eat. The children's BMIs were unrelated to any variables measured in the study. r