Physical activity and obesity

Gender-specific determinants of overweight and obesity among older adults in India: evidence from a cross-sectional survey, 2017-18

BACKGROUND

A major societal trend of the twenty-first century is the rapidly ageing population as a consequence of the decline in fertility and increase in life expectancy. Along with the rise in ageing population, the burden of obesity and related non-communicable diseases is also equally rising. In this study, we aimed to investigate the potential gender-specific determinants of overweight and obesity among older adults in India.

SUBJECTS AND METHODS

The present study used data from the Longitudinal Ageing Study in India (LASI) wave 1 (2017-18). A total sample of 25,952 older adults (≥ 60 years) was selected for the study. Descriptive statistics, bivariate chi-square test, and logistic regression estimation were applied to accomplish the study objectives. Body mass index (BMI) has been classified in this study according to the WHO criteria.

RESULTS

The prevalence of overweight was higher among women (18.15% in rural areas and 46.62% in urban areas) compared to men (12.9% in rural areas and 30.61% in urban areas). Similarly, obesity was higher among women than men who were residing in urban areas (17.07% vs. 5.37%), had secondary or above education (32.38% vs. 6.1%) belonged to richest strata (16.37% vs. 4.50%), or had mobility impairment (9.2% vs. 2.8%). Despite adjustment for several confounders, women were more likely to be overweight (OR: 2.18; CI: 1.86, 2.55) and obese (OR: 3.79; CI: 2.86, 5.03) than men. However, among both the elderly men and women, those who were highly educated were 2.29 times (OR: 2.29; CI: 1.80, 4.11) and 2.71 times (OR: 2.71; CI: 1.78, 4.11), respectively more likely to be overweight than their illiterate counterparts. Older adults living in urban areas were more likely to suffer from obesity compared to rural men (OR: 1.47; CI: 1.07, 2.02) and women (OR: 2.58; CI: 1.85, 3.60). Both men and women, who were highly educated were 2.64 times (OR: 2.64; CI: 1.71, 4.09) and 2.94 times (OR: 2.94; CI: 1.40, 6.20), respectively, more likely to be obese than their illiterate counterparts. Older men and women who were richest (OR: 1.60; CI: 1.19, 2.14 & OR: 2.12; CI: 1.63,2.76), or had mobility impairment (OR: 1.33; CI: 1.09,1.61 & OR: 1.72; CI: 1.42,2.08) were more likely to be overweight than their counterparts who were poorest or did not have any mobility limitation, respectively.

CONCLUSIONS

This study found increased vulnerability of overweight and obesity among older women than men irrespective of their socioeconomic, demographic, and health status. The present study suggests that introducing preventative measures such as campaigns to encourage physical activity, and community awareness may help reduce the high burden of overweight and obesity. Finally, the findings are important for better functioning of any public health programme and suitable intervention techniques to maintain a healthy body in order to lower the prevalence and risk factors of non-communicable diseases in later life.

Neighbourhood crime and obesity: Longitudinal evidence from Australia

RATIONALE

Obesity remains a significant public health concern globally with over one billion adults projected to be obese by 2025. To better understand the drivers of obesity and to inform policy, it is important to explore the factors that influence obesity.

OBJECTIVES

The objective of this paper to examine if the crime rates in the neighbourhood or local area in which a person lives influences their likelihood of being obese. Thus, we seek to contribute to the literature on the determinants of obesity by asking the question: what is the effect of neighbourhood (i.e., postcode) crime on obesity? We also examine the pathways through which neighbourhood crime influences obesity with a focus on the role of social capital, physical activity and sleep quality.

METHODS

Using 14 waves of longitudinal data from the Household, Income and Labour Dynamics in Australia (HILDA) survey merged with official police statistics on crime rates at the postcode level, we apply identification strategies that address endogeneity arising from endogenous sorting and omitted variable bias.

RESULTS

We find that an increase in neighbourhood crime rates is associated with an increase in body mass index (BMI) and the likelihood of being obese. Exploring the pathways through which neighbourhood crime influences obesity, we find that social capital and physical activity are important channels, while sleep quality is not. The evidence also suggests that the effects of violent crime are more pronounced compared to property crime.

CONCLUSION

Our findings suggest that targeting crime, and in particular violent crime, which seems to be driving the findings, is a core mechanism for reducing BMI and maintaining healthy body weight. The mediating role of physical activity and social capital also suggest that public policy can specifically target these areas by providing interventions that promote social capital and physical activity even amidst high crime rates.

Socio-demographic and behavioral correlates of excess weight and its health consequences among older adults in India: Evidence from a cross-sectional study, 2017-18

BACKGROUND

Rapid population aging is expected to become one of the major demographic transitions in the twenty-first century due to the continued decline in fertility and rise in life expectancy. Such a rise in the aged population is associated with increasing non-communicable diseases. India has suffered from obesity epidemic, with morbid obesity affecting 5% of the population and continuing an upward trend in other developing countries. This study estimates the prevalence of excess weight among older adults in India, and examines the socio-demographic and behavioral factors and its health consequences.

METHODS

The study used data from the Longitudinal Ageing Study in India (LASI) wave 1 (2017-18). A total sample of 25,952 older adults (≥ 60 years) was selected for the study. Descriptive statistics, bivariate Chi-Square test, and logistic regression models were applied to accomplish the study objectives. Body mass index (BMI) has been computed for the study according to the classification of the World Health Organization, and "excess weight" refers to a score of BMI ≥ 25.0 kg/m2.

RESULTS

Overall, 23% of older adults (≥ 60 years) were estimated with excess weight in India, which was higher among women irrespective of socioeconomic and health conditions. The higher levels of excess weight (than the national average of ≥22.7%) were observed among older adults in states like Haryana, Tamil Nadu, Telangana, Maharashtra, Gujarat, Manipur, Goa, Kerala, Karnataka, Himachal Pradesh, Punjab, Sikkim and some other states. After adjusting for selected covariates, the odds of excess weight were higher among females than males [OR: 2.21, 95% CI: 1.89, 2.60]. Similarly, the likelihood of excess weight was 2.18 times higher among older adults who were living in urban areas compared to their rural counterparts [OR: 2.18; 95% CI: 1.90, 2.49]. Higher level of education is significantly positively correlated with excess weight. Similarly, higher household wealth index was significantly positively correlated with excess weight [OR: 1.98, CI: 1.62, 2.41]. Having hypertension, diabetes and heart diseases were associated with excess weight among older adults. Regional variations were also observed in the prevalence of excess weight among older adults.

CONCLUSION

The findings suggest that introducing measures that help to reduce the risk of non-communicable diseases, and campaigns to encourage physical activity, and community awareness may help reduce the high burden of excess weight and obesity among older Indians. The findings are important for identifying the at-risk sub-populations and for the better functioning of any public health programme and suitable intervention techniques to lower the prevalence and risk factors for excess weight in later life.

Short-Term Growth Hormone Administration Mediates Hepatic Fatty Acid Uptake and De Novo Lipogenesis Gene Expression in Obese Rats

Obesity has been linked to metabolic syndrome, type 2 diabetes, and non-alcoholic fatty liver disease (NAFLD). Obesity causes a decrease in growth hormone (GH) levels and an increase in insulin levels. Long-term GH treatment increased lipolytic activity as opposed to decreasing insulin sensitivity. Nonetheless, it is possible that short-term GH administration had no impact on insulin sensitivity. In this study, the effect of short-term GH administration on liver lipid metabolism and the effector molecules of GH and insulin receptors were investigated in diet-induced obesity (DIO) rats. Recombinant human GH (1 mg/kg) was then administered for 3 days. Livers were collected to determine the hepatic mRNA expression and protein levels involved in lipid metabolism. The expression of GH and insulin receptor effector proteins was investigated. In DIO rats, short-term GH administration significantly reduced hepatic fatty acid synthase (FASN) and cluster of differentiation 36 (CD36) mRNA expression while increasing carnitine palmitoyltransferase 1A (CPT1A) mRNA expression. Short-term GH administration reduced hepatic FAS protein levels and downregulated gene transcription of hepatic fatty acid uptake and lipogenesis, while increasing fatty acid oxidation in DIO rats. DIO rats had lower hepatic JAK2 protein levels but higher IRS-1 levels than control rats due to hyperinsulinemia. Our findings suggest that short-term GH supplementation improves liver lipid metabolism and may slow the progression of NAFLD, where GH acts as the transcriptional regulator of related genes.

Association of sleep duration with sarcopenic obesity in multi-ethnic older adults: findings from the WCHAT Study

OBJECTIVE

Sarcopenic obesity is a prevalent geriatric syndrome, characterized by concurrence of sarcopenia and obesity. Sleep duration is linked to both obesity and sarcopenia. However, little was known regarding the association of sleep duration with sarcopenic obesity. In this study, we aimed to examine the association of sleep duration with sarcopenic obesity in multi-ethnic community-dwelling older adults.

METHODS

Sarcopenia was defined according to the criteria established by Asian Working Group for Sarcopenia (AWGS) 2019. Obesity was defined as body fat percentage above the 60th percentile specified by sex. Sarcopenic obesity was defined as concurrence of obesity and sarcopenia. Sleep duration was collected by a self-reported questionnaire and was further divided into 5 groups: "<6 h", "6-7 h", "7-8 h", "8-9 h" (reference group) and "≥9 h" (long sleep). Logistic regressions were adopted to examine the association.

RESULTS

2256 multi-ethnic adults aged 60 and over from the West China Health and Aging Trend (WCHAT) study were involved for present study. Overall, 6.25% of the participants were classified as sarcopenic obesity. In the fully adjusted model, long sleep duration (≥ 9 h) was significantly associated with sarcopenic obesity compared with reference group (OR = 1.81, 95%CI = 1.10-2.98, P = 0.019). However, in subgroup analysis, this association can only be observed in male (OR 1.98, 95% CI = 1.02-3.87, P = 0.043) not in female (OR = 1.83, 95%CI = 0.85-3.94, P = 0.118). Regarding ethnic difference, Han older adults with long sleep duration (≥ 9 h) presented increased risk of sarcopenic obesity while ethnic minorities did not.

CONCLUSION

This study disclosed that long sleep duration significantly increased the risk of sarcopenic obesity among older adults. And our findings highlight the critical role of assessing sleep duration to identify individuals at risk of sarcopenic obesity.

Effects of a Three-Month COVID-19 Lockdown on Body Mass and Nutritional Status of Lebanese Students Who Study Physical Education

This study investigated the effects of a three-month COVID-19 lockdown on the body mass of Lebanese students who study physical education and whether these changes reflected in distribution changes in underweight, normal weight, and overweight/obese status. Furthermore, the study investigated whether lockdown affected physical activity behavior and if students who reduced the frequency of training sessions were more likely to increase their body mass. Body mass and body height were assessed in 174 Lebanese physical education students immediately before and at the end of COVID-19 lockdown. Their training routine was assessed using by questionnaire. Wilcoxon signed-rank order assessed the effects of lockdown on body mass, while Chi square test tested the differences in distribution of underweight, normal weight, and overweight/obese status before and after the lockdown. In general, there was a significant (p < 0.001) small increase in body mass. However, about 27% of participants had a moderate to major increase in body mass. This was reflected in a significant shift in nutritional status as the number of overweight/obese students increased by 5.2%. In addition, students who reduced their training frequency due to lockdown were three times more likely to increase body mass than those who remained active (i.e., 38 vs. 5 with moderate to major increase). Given that an increase in body mass increases all health risks, remaining physically active is of high importance for health prevention, especially considering all other positive effects of physical activity on cardio-respiratory and muscle function.

Does engagement in frequent physical activity improve diabetes mellitus among older adults in India? A propensity score matching approach

BACKGROUND AND AIMS

Diabetes is a major chronic condition and was identified as one of the four priority non-communicable diseases that the United Nations targeted because of its increasing disease burden. The present study aims to examine the impact of physical activity on improving diabetes mellitus among older adults in India.

METHODS

This study utilizes data from India's first nationally representative longitudinal ageing survey (2017-18). Descriptive along with bivariate analysis was used to present the preliminary results. Additionally, Propensity score matching (PSM) analysis was used.

RESULTS

About 14% of older adults suffered from diabetes. Eighteen percent of older adults did frequent physical activity. The estimated average treatment effect on the treated (ATT) values in treated and control groups were 0.123 and 0.147, respectively, indicating that the prevalence of diabetes among older adults was reduced by 2.5% points because of frequent physical activity. The average treatment effect on the untreated (ATU) results indicates that among older adults who did not do frequent physical activity, if they did frequent physical activity, the prevalence of diabetes is likely to decrease by 2.2% points.

CONCLUSION

Our findings show that frequent physical activity is associated with a lower risk of diabetes in older adults. The results underscore the need to develop strategies of promoting an active lifestyle by maintaining physical activity to combat the diabetes epidemic in the older population.

Climate change, 24-hour movement behaviors, and health: a mini umbrella review

BACKGROUND

The worsening climate change and alarming prevalence of communicable and non-communicable diseases continue to threat human life and existence. Accumulating evidence suggests that favorable patterns of 24-h movement behaviors, high physical activity, low sedentary behavior, and adequate sleep, may positively contribute to achieving dual benefits of climate change mitigation and disease prevention. The purposes of this mini umbrella review were to summarize the most up-to-date, high-level evidence exploring the relationships between climate change, 24-h movement behaviors, and health and elaborate on the mechanisms linking the three variables of interest.

METHODS

A systematic search of electronic databases was performed in PubMed and Google Scholar during March-October 2020. Inclusion criteria were: (1) systematic review; (2) reviewed relationships between climate change and movement behaviors and/or health in any directions; (3) written in English; (4) published in 2010-2020. Narrative synthesis was conducted to highlight the main relationships observed and address the current state of knowledge and priorities for future research. In order to illustrate the potential mechanisms between climate change, movement behaviors, and health, the main results from included systematic reviews were summarized and a conceptual framework was developed for future research.

RESULTS

Based on the evidence from eight systematic reviews published in the past decade, multi-directional (i.e., uni-, bi-, or U-shaped) links were observed between climate change and varying human health outcomes. However, little is understood about the association between climate change and 24-h movement behaviors. Two reviews suggested the negative impact of climate change on sleep and bi-directional relationships between climate change and physical activity/sport. One review included two studies suggesting the unfavorable impact of climate change on sedentary behavior; however, the evidence was limited. Finally, no reviews examined the mechanisms by which climate change, movement behaviors, and health impact one another. Based on the findings of this mini umbrella review, a conceptual framework is proposed that could guide future work to unpack mechanisms between climate change, movement behaviors, and health.

CONCLUSIONS

This mini umbrella review highlights the importance of better understanding the mechanisms between climate change, movement behaviors, and health in developing effective mitigation and adaptation strategies to climate change, while paying close attention to vulnerable countries/communities/population groups.

Adolescent Obesity and Eating Disorders: Can Calorie Restriction have a Positive Impact

Background:

The current obesogenic environment with relatively increased affordability and availability of high calorie food and beverages, has led to an alarming increase in the prevalence of obesity and related lifestyle disorders in children and adolescents, predisposing them to accelerated aging. The increased prevalence may be due to the eating behavior of adolescents, their genetic and molecular etiology and/or due to the impact of psychological stress and their wrong lifestyle choices. Calorie restriction has been extensively researched for reducing the obesity in adolescents and adults but is yet to be successfully implemented.

Objective:

The present review paper focuses on the types of calorie restriction diets, the role of its mimics and the nutrigenomic mechanisms that may be helpful in reducing obesity and related disorders in the adolescents. The role of behavioral therapeutic techniques and physical activity has also been highlighted in addition to the calorie restricted diet for bringing about an overall lifestyle modification in the management of obesity.

Conclusion:

Food preferences are acquired in childhood and sound nutritional practices should be established in childhood to prevent lifestyle disorders and premature aging. Though CR is a known and preferred non-pharmacological intervention in the management of obesity, its implemention has not been explored and evaluated extensively. This is a vital area that needs scientific research as the goals of obesity managements are no longer just weight loss through dietary restrictions. An interdisciplinary method to lifestyle modification in the management of adolescent obesity addressing all physiological and psychosocial aspects is recommended.

Association of dietary total antioxidant capacity to anthropometry in healthy women: A cross-sectional study

OBJECTIVES

Reactive oxygen species level is a fundamental component in the pathogenesis of obesity that might be reduced by dietary antioxidants. Measurement of dietary total antioxidant capacity (DTAC) is regarded as a new holistic dietary index. Given the limited research on DTAC, the aim of this study was to examine the association of DTAC with obesity-related features in women.

METHODS

The present cross-sectional study included 627 female participants. Data on dietary intake were assessed using a validated food frequency questionnaire. DTAC was estimated through total reactive antioxidant potential (TRAP), Trolox equivalent antioxidant capacity (TEAC), and ferric reducing ability of plasma (FRAP). Anthropometric parameters (body mass index and waist circumference), were investigated using standard methods.

RESULTS

After adjustment for possible covariates, both TRAP and TEAC were significantly positively associated with obesity (TRAP: OR, 1.65; 95% confidence interval [CI], 1.04-2.63; P_trend, 0.03; TEAC: OR, 1.63; 95% CI, 1.01-2.63; P_trend, 0.04). However, there was no association between FRAP and obesity (OR_, 1.11; 95% CI, 0.64-1.93; P_trend, 0.68). Moreover, no relationship was found between different DTAC indices and waist circumference (TRAP: OR, 1.13; 95% CI, 0.70-1.80; P_trend, 0.60; TEAC: OR, 1.04; 95% CI, 0.64-1.69; P_trend, 0.87; FRAP: OR, 0.86; 95% CI, 0.49-1.51; P_trend, 0.62).

CONCLUSION

Women with higher DTAC scores had higher risk for obesity. No association was found between DTAC and waist circumference.

Prolonged high-fat-diet feeding promotes non-alcoholic fatty liver disease and alters gut microbiota in mice

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become an epidemic largely due to the worldwide increase in obesity. While lifestyle modifications and pharmacotherapies have been used to alleviate NAFLD, successful treatment options are limited. One of the main barriers to finding safe and effective drugs for long-term use in NAFLD is the fast initiation and progression of disease in the available preclinical models. Therefore, we are in need of preclinical models that (1) mimic the human manifestation of NAFLD and (2) have a longer progression time to allow for the design of superior treatments.

AIM

To characterize a model of prolonged high-fat diet (HFD) feeding for investigation of the long-term progression of NAFLD.

METHODS

In this study, we utilized prolonged HFD feeding to examine NAFLD features in C57BL/6 male mice. We fed mice with a HFD (60% fat, 20% protein, and 20% carbohydrate) for 80 wk to promote obesity (Old-HFD group, n = 18). A low-fat diet (LFD) (14% fat, 32% protein, and 54% carbohydrate) was administered for the same duration to age-matched mice (Old-LFD group, n = 15). An additional group of mice was maintained on the LFD (Young-LFD, n = 20) for a shorter duration (6 wk) to distinguish between age-dependent and age-independent effects. Liver, colon, adipose tissue, and feces were collected for histological and molecular assessments.

RESULTS

Prolonged HFD feeding led to obesity and insulin resistance. Histological analysis in the liver of HFD mice demonstrated steatosis, cell injury, portal and lobular inflammation and fibrosis. In addition, molecular analysis for markers of endoplasmic reticulum stress established that the liver tissue of HFD mice have increased phosphorylated Jnk and CHOP. Lastly, we evaluated the gut microbial composition of Old-LFD and Old-HFD. We observed that prolonged HFD feeding in mice increased the relative abundance of the Firmicutes phylum. At the genus level, we observed a significant increase in the abundance of Adercreutzia, Coprococcus, Dorea, and Ruminococcus and decreased relative abundance of Turicibacter and Anaeroplasma in HFD mice.

CONCLUSION

Overall, these data suggest that chronic HFD consumption in mice can mimic pathophysiological and some microbial events observed in NAFLD patients.

Sedentary Time, Physical Activity, and Sleep Duration: Associations with Body Composition in Fibromyalgia. The Al-Andalus Project

To explore the individual–independent relationships of sedentary time (ST) and physical activity (PA) (light and moderate-to-vigorous intensity (MVPA)), with sleep duration and body composition (waist circumference, body mass index (BMI), body fat percentage, and muscle mass index) in women with fibromyalgia, and to determine whether these associations are independent of physical fitness. This cross-sectional study involved 385 women with fibromyalgia. ST and PA were assessed by triaxial accelerometry, sleep duration was self-reported. Waist circumference was measured using an anthropometric tape, and body weight, body fat percentage, and muscle mass were estimated using a bio-impedance analyzer. In individual regression models, ST and sleep were directly associated with waist circumference, BMI, and body fat percentage (β between 0.10 and 0.25; all p < 0.05). Light PA and MVPA were inversely associated with waist circumference, BMI, and body fat percentage (β between −0.23 and −0.12; all p < 0.05). In multiple linear regression models, ST (β between 0.17 and 0.23), light PA (β between −0.16 and −0.21), and sleep duration (β between 0.11 and 0.14) were independently associated with waist circumference, BMI, and body fat percentage (all p < 0.05). MVPA was associated with waist circumference independent of light physical activity (LPA) and sleep duration (β = −0.11; p < 0.05). Except for MVPA, these associations were independent of physical fitness. These results suggest that longer ST and sleep duration, and lower PA levels (especially light intensity PA), are independently associated with greater adiposity, but not muscle mass, in women with fibromyalgia. These associations are, overall, independent of physical fitness.

Clustered Patterns of Behavioral and Health-Related Variables Among Young Lesbian Women

Lesbian women are at increased risk for a variety of mental and physical health problems compared to heterosexual women. In order to inform treatment and prevention, the purpose of this study was to examine behavioral and health-related patterns among lesbian women and elucidate how these patterns are associated with general discrimination, sexual minority stress, affect, and social support. A sample of self-identified lesbian women (N = 436) completed an online survey from August 2014-March 2015. A latent profile analysis was conducted using measures of body mass index, hazardous alcohol use, binge eating, eating disorder risk, and exercise as indicators. A 5-class solution best fit the data and included two healthy groups: (a) low health risk, moderate exercise (54%), (b) low health risk + high exercise (22%); and three unhealthy risk groups: (c) obese + binge eating (14%); (d) disordered eating + hazardous alcohol use (5%); (e) disordered eating + high exercise (5%). The three unhealthy classes generally reported more general discrimination, sexual minority stress, social anxiety, negative affect, and lower social support compared to the healthy classes. These findings show that behavioral and health-related variables cluster together in several distinct patterns among lesbian women. In addition, general discrimination and sexual minority stress and associated psychosocial functioning may be related to these maladaptive behavioral and health-related patterns and may be important to consider in behavioral interventions.

Associations between self-reported and objectively measured physical activity and overweight/obesity among adults in Kota Bharu and Penang, Malaysia

BACKGROUND

For the past decades, Malaysia has seen an increased prevalence of overweight and obesity which leads to significant health threats. Physical activity is beneficial in maintaining healthy body weight. The objective of this study was to measure physical activity of adults in Malaysia using objective measurement (accelerometer) and self-reported methods, as well as to determine their associations with (body mass index (BMI) and waist circumference (WC) measurements.

METHODS

Four-hundred and ninety Malaysian adults (n = 490) aged 20 to 65 years old participated in this cross-sectional study. Their body weight, height, and WC measurements were measured according to standard procedures. Physical activity was assessed objectively with accelerometers for five to seven consecutive days. The International Physical Activity Questionnaire (IPAQ) was used to estimate the amount of time spent on various domains of physical activity. Mixed models were used to determine the associations between physical activity variables and both BMI and WC.

RESULTS

The mean value of objectively measured moderate-to-vigorous physical activity (MVPA) was 13.5 min per day, in which male participants recorded a significantly higher amount of time compared to females. On the other hand, the mean self-reported total physical activity was 380 min per week; male participants reported a significantly higher amount of time on physical activity in the occupation/work and leisure/recreation domains while female participants spent significantly more time in the domestic/household chores domain. We also observed that the mean values of objectively measured total MVPA, self-reported time spent on walking for leisure/recreation, and total time amount of time spent on MVPA for leisure/recreation were significantly higher among participants with BMI of less than 25 kg/m2. The final statistical model yielded a significant negative association between objectively measured total MVPA and BMI, but not with WC measurement. No significant association was reported between self-reported total physical activity with BMI and WC measurement.

CONCLUSIONS

Objectively measured MVPA was inversely associated with BMI, but not WC measurement. No significant association was observed between self-reported total physical activity and physical activity time measures across domains with both BMI and WC measurement.

Association between DNA methylation in obesity-related genes and body mass index percentile in adolescents

Childhood obesity remains an epidemic in the U.S. and worldwide. However, little is understood regarding the epigenetic basis of obesity in adolescents. To investigate the cross-sectional association between DNA methylation level in obesity-related genes and body mass index (BMI) percentile, data from 263 adolescents in the population-based Penn State Child Cohort follow-up exam was analysed. Using DNA extracted from peripheral leukocytes, epigenome-wide single nucleotide resolution of DNA methylation in cytosine-phosphate-guanine (CpG) sites and surrounding regions was obtained. We used multivariable-adjusted linear regression models to assess the association between site-specific methylation level and age- and sex-specific BMI percentile. Hypergeometric and permutation tests were used to determine if obesity-related genes were significantly enriched among all intragenic sites that achieved a p < 0.05 throughout the epigenome. Among the 5,669 sites related to BMI percentile with p < 0.05, 28 were identified within obesity-related genes. Obesity-related genes were significantly enriched among 103,466 intragenic sites (P_{hypergeometric} = 0.006; P_permutation = 0.006). Moreover, increased methylation on one site within SIM1 was significantly related to higher BMI percentile (P = 4.2E-05). If externally validated, our data would suggest that DNA methylation in obesity-related genes may relate to obesity risk in adolescents.

Household income, active travel, and their interacting impact on body mass index in a sample of urban Canadians: a Bayesian spatial analysis

Background

Active travel for utilitarian purposes contributes to total physical activity and may help counter the obesity epidemic. However, the evidence linking active travel and individual-level body weight is equivocal. Statistical modeling that accounts for spatial autocorrelation and unmeasured spatial predictors has not yet used to explore whether the health benefits of active travel are shared equally across socioeconomic groups.

Methods

Bayesian hierarchical models with spatial random effects were developed using travel survey data from Saskatoon, Canada (N = 4625). Differences in log-transformed body mass index (BMI) were estimated for levels of active travel use (vehicular travel only, mixed vehicular/active travel, and active travel only), household income, and neighbourhood deprivation after controlling for sociodemographic and physical activity variables. The modifying effect of household income on the association between active travel and BMI was also evaluated.

Results

Significant and meaningful decreases in BMI were observed for mixed (β = − 0.02, CrI − 0.036 to − 0.004) and active only (β = − 0.043, CrI − 0.06 to − 0.025) compared to vehicular only travelers. BMI was significantly associated with levels of household income and neighbourhood deprivation. Accounting for the interaction between travel mode and household income, decreases in BMI were observed for active only compared to vehicular only travellers in the highest income category (β = − 0.061, CrI − 0.115 to − 0.007).

Conclusion

Strategies to increase active travel use can support healthy weight loss and maintenance, but the opportunity to benefit from active travel use may be limited by low income. Considerations should be given to how interventions to increase active transportation might exacerbate social inequalities in BMI. Spatial statistical models are needed to account for unmeasured but spatially structured neighbourhood factors.

Electronic supplementary material

The online version of this article (10.1186/s12942-019-0168-x) contains supplementary material, which is available to authorized users.

A crowdsourcing approach to understand weight and weight loss in men

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Crowdsourcing can be used to detect unexpected barriers to male weight loss.

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Some unique behaviors related to high BMI were revealed including watching others play video games.

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Novel behaviors to target: less watching video games and more organized physical activity

The Dose Makes the Poison: Sugar and Obesity in the United States - a Review

Two-thirds of the US population is either overweight or obese. Obesity is one of the major drivers of preventable diseases and health care costs. In the US, current estimates for these costs range from $147 to $210 billion per year. Obesity is a multifactorial disease: genetics, lifestyle choices, metabolism, and diet. Low-fat diets have been suggested as the key to weight management. However, over the past 30 years, the calories from fat in people's diets have gone down, but obesity rates keep climbing. Evidence suggests that diets high in added sugar promote the development of obesity. However, the impact of sugar consumption on weight gain and body fat accumulation remains a controversial topic. Therefore, the aim of this review is to provide basic framework information about the prevalence of obesity and sugar consumption in the US over the last five decades. We also review the process by which sugar is converted to fat and stored in the human body. The relationship between sugar consumption and obesity was analyzed using United States Department of Agriculture (USDA) Sugar and Sweetener Outlook data, and obesity prevalence was analyzed using data from the Centers for Disease Control and Prevention (CDC). The analysis revealed a reduction in sugar consumption concurrent with a slowing down of the annual rate of increase of obesity. However, although the data show that the sugar consumption trend is going in the right direction (declining), the US population still consumes more than 300% of the recommended daily amount of added sugar.

Obese zebrafish: A small fish for a major human health condition

Obesity is becoming a silent worldwide epidemic, with a steady increase in both adults and children. To date, even though several drugs have been licensed for long-term obesity treatment, none of them are yet used in routine clinical practice. So far the only successful intervention has been behavioral therapy. A suitable and economic experimental model mimicking the human condition would therefore be extremely useful to evaluate preventive measures and novel treatments. Zebrafish are emerging as an important model system to study obesity and related metabolic disease. Remarkable similarities have been reported in lipid metabolism and the adipogenic pathway between zebrafish and mammals. Moreover, the zebrafish possesses a number of features-the relative inexpensiveness of animal husbandry, its optical transparency and the ability to produce a large number of offspring at low cost-that make it ideal for large-scale screening and for testing drugs and intervention. In this review, we summarize recent progress in using zebrafish as a model system to study obesity and obesity-related metabolic disorders. We describe several zebrafish models (in both larvae and adult animals) that develop obesity and non-alcoholic fatty liver disease (NAFLD) using different approaches, including gene manipulation, diet manipulation and modification of microbiota composition. For these models, we have outlined the specific aspects related to obesity and its development and we have summarized their advantages and limitations.

Obesity, Hypertension, and Type-2 Diabetes Mellitus: The Interrelationships and the Determinants among Adults in Gaza City, Palestine

OBJECTIVES

To describe the distribution of social factors, lifestyle habits and anthropometric measurements according to hypertension and Type-2 diabetes.

METHODS

A cross-sectional study was conducted in Gaza City, Palestine that included 379 patients (20-60 years) who had hypertension and/or diabetes. Three groups of patients were involved; 106 hypertensive (HT), 109 diabetic (T2DM) and 164 hypertensive diabetics (HT + T2DM).

RESULTS

The HT + T2DM group were older and had a higher body mass index compared to HT and T2DM groups. There were 62.3% patients who were female, 49.2% were highly educated HT patients, and 49.3% patients had a low level of education and were HT + T2DM. There were 55.8% patients who lived in large families. Patients who were passive smokers or never smoked before were mostly HT + T2DM, while active smokers and past smokers had T2DM. There were 48.2% patients who were highly physically active who had HT, 40.9% whom were moderately active had T2DM, and 53.8% of patients who had a low level of activity were HT + T2DM. Multivariate linear regression showed that having a diseased mother, living in a large family, being a past or passive smoker, or never having smoked, having a low or moderate level of activity, and having HT or HT + T2DM, were significantly associated with an increased body mass index.

CONCLUSION

Parental health/disease conditions and environmental factors (social network and lifestyle habits) played the greatest role in the development of obesity and disease.

Physical Activity Levels and Cardiometabolic Risks in Obese African American Adults: A Pilot Intervention Study

Limited information is available regarding the effects of physical activity on risks of cardiometabolic diseases among obese African American adults. We conducted a church-based 12-week weight control and cardiometabolic risk reduction intervention (n=30, 22 females, 56.7±11.4 years old, BMI 37.4±6.7 kg/m2), after which body weight was slightly reduced (98.3±18.4 and 97.3±19 kg, p=.052); body fat percentage was significantly decreased among males (34.7±8.9 to 28.5±8.4 %; p=.049); and walking steps were increased, but not significantly. Among measured cardiometabolic risk biomarkers, hemoglobin A1c (HbA1c) was decreased significantly (6.8±1.1 to 6.1±1.1%; p=.0004) while time spent in sedentary behaviors was associated with less favorable change in total cholesterol (β=11.49, SE=3.55, p=.003) and tumor necrosis factor (TNF-α, β=0.3, SE=0.13, p=.038). Our study shows that adiposity reduction was feasible through a short-term healthy lifestyle program for obese African American adults, and suggests that reducing sedentary behaviors through light physical activity might lead to a decrease in cardiovascular risks.

Acceptance of different design exergames in elders

For promoting the successful aging of elderly residents of Chang Gung Silver Village in Taiwan, five interactive exergames were developed to promote the well-being of the elderly. The exergames included both physical games and cognitive games, and were implemented using various computer-based technologies in the Chang Gung Silver Village. The exergames were trialed by 39 elderly residents (15 male, 24 female; mean age 79.5 ± 17.5 years) of Chang Gung Silver Village. Following the trials, the participants were requested to complete a Technology Acceptance Model 2 (TAM2) questionnaire. The results showed that the perceived playfulness and perceived usefulness of the exergames were significantly related to the users’ usage behavior and intention to use for both the physical games and the cognitive games. However, a relationship between the output quality of the game and the usage behavior was apparent only in the case of the cognitive exergames. Finally, the impact of social influence on the intention to use and the usage behavior was more pronounced for the physical exergames. Overall, the results revealed that the acceptance of exergames by the elderly depends not so much on the awareness of fun in using the game, but the perceived usefulness of the related physical and cognitive abilities.

Understanding physical (in-) activity, overweight, and obesity in childhood: Effects of congruence between physical self-concept and motor competence

Both the physical self-concept and actual motor competence are important for healthy future physical activity levels and consequently decrease overweight and obesity in childhood. However, children scoring high on motor competence do not necessarily report high levels of physical self-concept and vice versa, resulting in respective (in-) accuracy also referred to as (non-) veridicality. This study examines whether children’s accuracy of physical self-concept is a meaningful predictive factor for their future physical activity. Motor competence, physical self-concept and physical activity were assessed in 3^rd grade and one year later in 4^th grade. Children’s weight status was categorized based on WHO recommendations. Polynomial regression with Response surface analyses were conducted with a quasi-DIF approach examining moderating weight status effects. Analyses revealed that children with higher motor competence levels and higher self-perceptions show greater physical activity. Importantly, children who perceive their motor competence more accurately (compared to less) show more future physical activity. This effect is strong for underweight and overweight/obese children, but weak for normal weight children. This study indicates that an accurate self-perception of motor competence fosters future physical activity beyond single main effects, respectively. Hence, the promotion of actual motor competence should be linked with the respective development of accurate self-knowledge.

Illustrating a "consequential" shift in the study of health inequalities: a decomposition of racial differences in the distribution of body mass

PURPOSE

We present a conceptual introduction to "distributional inequalities"-differences in distributions of risk factors or other outcomes between social groups-as a consequential shift for research on health inequalities. We also review a companion analytical methodology, "distributional decomposition", which can assess the population characteristics that explain distributional inequalities.

METHODS

Using the 1999-2012 U.S. National Health and Nutrition Examination Survey, we apply statistical decomposition to (a) document gender-specific, black-white inequalities in the distribution of body mass index (BMI) and, (b) assess the extent to which demographic (age), socioeconomic (family income, education), and behavioral predictors (caloric intake, physical activity, smoking, alcohol consumption) are associated with broader distributional inequalities in BMI.

RESULTS

Black people demonstrate favorable or no different caloric intake, smoking, or alcohol consumption than whites, but worse levels of physical activity. Racial inequalities extend beyond the obesity threshold to the broader BMI distribution. Demographic, socioeconomic, and behavioral characteristics jointly explain more of the distributional inequality among men than women.

CONCLUSIONS

Black-white distributional inequalities are present both among men and women, although the mechanisms may differ by gender. The notion of "distributional inequalities" offers an additional purchase for studying social inequalities in health.

The association between leisure-time physical activity and lung function in older adults: The English longitudinal study of ageing

The longitudinal association between physical activity and lung function is unclear. Therefore, we examined said association over eight years. This study included data from 2966 participants in English Longitudinal Study of Ageing (63±7years [mean±SD]), a prospective study of initially healthy, community dwelling adults. Physical activity was assessed using an interview and lung function using a spirometer at baseline (2004-5) and follow-up (2012-13). General linear regression was used to assess associations between activity and lung function. Logistic regression was used to assess the odds of new cases of abnormal lung function. Some 14% of participants were defined as physically inactive at baseline, 50% were classified into the moderate group, and 36% into the vigorous group. In comparison with remaining inactive at follow-up, remaining active was positively associated with forced vital capacity (FVC) (β=0.09, 95% confidence interval [CI]: 0.01, 0.17; p=0.02) and forced expiratory volume in one second (FEV-1) (β=0.09, 95% CI: 0.02, 0.15; p=0.01) after adjustment for baseline lung function score and other covariates. Using the fifth centile to define the lower limit of normal (that is, -1.64 z scores), there were lower odds of incident abnormal lung function in participants who remained physically active compared to those who remained inactive (FVC odds ratio=0.31, 95% CI: 0.17, 0.55. FEV-1 odds ratio=0.43, 95% CI: 0.26, 0.72). Similar associations were observed in those who became active. This study suggests that remaining physically active or becoming active in older age is positively associated with lung function and reduced odds of abnormal lung function.

Community gardening, community farming and other local community-based gardening interventions to prevent overweight and obesity in high-income and middle-income countries: protocol for a systematic review

INTRODUCTION

The worldwide prevalence of overweight/obesity has continued to rise over the last decades. To reverse this trend, public health authorities are exploring cost-effective interventions, especially in high-income and middle-income countries. Community gardening offers a unique opportunity for individuals to enhance physical activity levels and improve their diet. However, synthesised evidence on the short-term or long-term effectiveness and on the costs of community gardening interventions to prevent overweight/obesity remains limited. Therefore, this review will investigate: (1) the effectiveness of voluntary participation in community gardening compared with no or a control intervention on overweight/obesity and associated health outcomes, (2) effects on different subgroups of populations and (3) the costs of community gardening interventions.

METHODS AND ANALYSIS

We will conduct a systematic review, limited to evaluations of community gardening interventions with controlled quantitative and interrupted time series designs. To identify relevant articles, we will systematically search 12 academic and 5 grey literature databases, as well as 2 trial registers and 6 websites. Articles will then be assessed for eligibility based on a predefined set of criteria. At least two independent reviewers will assess each article for relevance, before evaluating the methodological quality and potential bias of the studies. Data relevant to the objectives of this review will be extracted and cross-validated. Any disagreements will be mediated by a third reviewer. If feasible, meta-analyses of primary outcomes (overweight/obesity, physical activity, food intake, energy intake) will be conducted. We will use the Grading of Recommendations Assessment, Development and Evaluation method to assess the overall quality of evidence.

ETHICS AND DISSEMINATION

For this review, no ethical approval is required as we will only extract and analyse secondary data. We aim to submit the final review manuscript to an open access journal for publication and disseminate results via conferences and social media.

TRIAL REGISTRATION NUMBER

International Prospective Register of Systematic Reviews (PROSPERO)(CRD42017043696).

Time spent in sedentary posture is associated with waist circumference and cardiovascular risk

BACKGROUND

The relationship between metabolic risk and time spent sitting, standing and stepping has not been well established. The present study aimed to determine associations of objectively measured time spent siting, standing and stepping, with coronary heart disease (CHD) risk.

METHODS

A cross-sectional study of healthy non-smoking Glasgow postal workers, n=111 (55 office workers, 5 women, and 56 walking/delivery workers, 10 women), who wore activPAL physical activity monitors for 7 days. Cardiovascular risks were assessed by metabolic syndrome categorisation and 10-year PROCAM (prospective cardiovascular Munster) risk.

RESULTS

Mean (s.d.) age was 40 (8) years, body mass index 26.9 (3.9) kg m^-2 and waist circumference 95.4 (11.9) cm. Mean (s.d.) high-density lipoprotein cholesterol (HDL cholesterol) 1.33 (0.31), low-density lipoprotein cholesterol 3.11 (0.87), triglycerides 1.23 (0.64) mmol l^-1 and 10-year PROCAM risk 1.8 (1.7)%. The participants spent mean (s.d.) 9.1 (1.8) h per day sedentary, 7.6 (1.2) h per day sleeping, 3.9 (1.1) h per day standing and 3.3 (0.9) h per day stepping, accumulating 14 708 (4984) steps per day in 61 (25) sit-to-stand transitions per day. In univariate regressions-adjusting for age, sex, family history of CHD, shift worked, job type and socioeconomic status-waist circumference (P=0.005), fasting triglycerides (P=0.002), HDL cholesterol (P=0.001) and PROCAM risk (P=0.047) were detrimentally associated with sedentary time. These associations remained significant after further adjustment for sleep, standing and stepping in stepwise regression models. However, after further adjustment for waist circumference, the associations were not significant. Compared with those without the metabolic syndrome, participants with the metabolic syndrome were significantly less active-fewer steps, shorter stepping duration and longer time sitting. Those with no metabolic syndrome features walked >15 000 steps per day or spent >7 h per day upright.

CONCLUSIONS

Longer time spent in sedentary posture is significantly associated with higher CHD risk and larger waist circumference.

Sweet Taste Perception is Associated with Body Mass Index at the Phenotypic and Genotypic Level

Investigations on the relationship between sweet taste perception and body mass index (BMI) have been inconclusive. Here, we report a longitudinal analysis using a genetically informative sample of 1,576 adolescent Australian twins to explore the relationship between BMI and sweet taste. First, we estimated the phenotypic correlations between perception scores for four different sweet compounds (glucose, fructose, neohesperidine dihydrochalcone (NHDC), and aspartame) and BMI. Then, we computed the association between adolescent taste perception and BMI in early adulthood (reported 9 years later). Finally, we used twin modeling and polygenic risk prediction analysis to investigate the genetic overlap between BMI and sweet taste perception. Our findings revealed that BMI in early adulthood was significantly associated with each of the sweet perception scores, with the strongest correlation observed in aspartame withr= 0.09 (p= .007). However, only limited evidence of association was observed between sweet taste perception and BMI that was measured at the same time (in adolescence), with the strongest evidence of association observed for glucose with a correlation coefficient ofr= 0.06 (p= .029) and for aspartame withr= 0.06 (p= .035). We found a significant (p< .05) genetic correlation between glucose and NHDC perception and BMI. Our analyses suggest that sweet taste perception in adolescence can be a potential indicator of BMI in early adulthood. This association is further supported by evidence of genetic overlap between the traits, suggesting that some BMI genes may be acting through biological pathways of taste perception.

Incidence and potential risk factors of obesity among Tehranian adults

AIM

Evaluating the incidence of obesity and its risk factors among Tehranian adults.

MATERIAL & METHODS

In this population-based cohort, non-obese participants, aged ≥20years, were followed for development of obesity (Body Mass Index (BMI) ≥30). Incidence density and cumulative incidence rates of obesity were calculated for each sex. Cox proportional hazard regression was used to determine the association of potential obesity risk factors including: age, BMI, metabolic syndrome, waist circumference (WC), smoking, marital status, education, and physical activity.

RESULT

A total of 7257 participants (3536 men) were followed for a median of 8years. At baseline, mean age, BMI and WC were 41.3±14.6years, 25.1±2.9kg/m(2) (24.9±3kg/m(2) men and 25.2±3kg/m(2) women), and 84.8±9.8cm (87.06±9.2cm men and 82.6±9.9cm women) respectively. During the follow-up, 1345 participants (876 women) developed obesity contributing to cumulative incidences of 31.3% (CI: 29.9%-32.7%), 38.1% (CI: 36.2%-40.1%), and 23.4% (CI: 21.6%-25.3%) for the whole population, women, and men, respectively. Corresponding incidence density rates per 1000 person-year were 25.9 (CI: 24.5-27.3), 33.67 (CI: 31.5-36.0), and 18.0 (CI: 16.5-19.7), respectively. Highest incidence rates were observed during their 40s and 20s for women and men, respectively. Participants with metabolic syndrome, lower educational level, higher BMI and WC, were at higher risk of obesity development in both sexes.

CONCLUSION

High incidence of obesity was observed among Tehranian adults with higher incidence of obesity in women. Different modifiable variables may act as risk factors for obesity development which should be targeted to control the epidemic of obesity.

Effectiveness of Facebook-Delivered Lifestyle Counselling and Physical Activity Self-Monitoring on Physical Activity and Body Mass Index in Overweight and Obese Adolescents: A Randomized Controlled Trial

Background. The aim was to evaluate the effects of a 12-week, Facebook-delivered lifestyle counselling intervention, with or without physical activity self-monitoring, on physical activity and body mass index (BMI) in overweight and obese 13–16-year-old adolescents. Methods. Three-arm randomized controlled trial. Participants (n = 46) were randomly assigned to intervention and control groups: one group received Facebook-delivered lifestyle counselling and monitoring of their physical activity (Fb + Act, n = 15), whereas a second experimental group received the same Facebook-delivered lifestyle counselling without self-monitoring (Fb, n = 16) and a third group served as the control group (n = 15). Objective and self-reported physical activity assessment were used. Nonparametric statistical tests were used. Results. There were no significant intervention effects in terms of changes in physical activity levels or BMI from baseline to the 12-week postintervention measurements between the intervention and control groups. The Fb + Act group had lower sedentary time on weekdays compared to the control group during postintervention measurements (p = 0.021), but there was no interaction between time and group. Conclusions. Interventions were not effective at increasing physical activity in overweight and obese adolescents. Before implementing such interventions, more evaluations on their effectiveness are needed. This trial is registered with ClinicalTrials.gov identifier NCT02295761 (2014-11-17).

Role of MCP-1 on inflammatory processes and metabolic dysfunction following high-fat feedings in the FVB/N strain

Background

MCP-1 is known to be an important chemokine for macrophage recruitment. Thus, targeting MCP-1 may prevent the perturbations associated with macrophage-induced inflammation in adipose tissue. However, inconsistencies in the available animal literature have questioned the role of this chemokine in this process. The purpose of this study was to examine the role of MCP-1 on obesity-related pathologies.

Methods

Wild-type (WT) and MCP-1 deficient mice on an FVB/N background were assigned to either low-fat-diet (LFD) or high-fat-diet (HFD) treatment for a period of 16 weeks. Body weight and body composition were measured weekly and monthly, respectively. Fasting blood glucose and insulin, and glucose tolerance were measured at 16 weeks. Macrophages, T cell markers, inflammatory mediators, and markers of fibrosis were examined in the adipose tissue at sacrifice.

Results

As expected, HFD increased adiposity (body weight, fat mass, fat percent, and adipocyte size), metabolic dysfunction (impaired glucose metabolism and insulin resistance) macrophage number (CD11b⁺F480⁺ cells, and gene expression of EMR1 and CD11c), T cell markers (gene expression of CD4 and CD8), inflammatory mediators (pNFκB and pJNK, and mRNA expression of MCP-1, CCL5, CXCL14, TNF-α, and IL-6), and fibrosis (expression of IL-10, IL-13, TGF-β, and MMP2) (P<0.05). However, contrary to our hypothesis, MCP-1 deficiency exacerbated many of these responses resulting in a further increase in adiposity (body weight, fat mass, fat percent and adipocyte size), metabolic dysregulation, macrophage markers (EMR1), inflammatory cell infiltration, and fibrosis (formation of type I and III collagens, mRNA expression of IL-10 and MMP2) (P<0.05).

Conclusions

These data suggest that MCP-1 may be a necessary component of the inflammatory response required for adipose tissue protection, remodeling, and healthy expansion in the FVB/N strain in response to HFD feedings.

Cross-national comparison of socioeconomic inequalities in obesity in the United States and Canada

INTRODUCTION

Prior cross-national studies of socioeconomic inequalities in obesity have only compared summary indices of inequality but not specific, policy-relevant dimensions of inequality: (a) shape of the socioeconomic gradient in obesity, (b) magnitude of differentials in obesity across socioeconomic levels and, (c) level of obesity at any given socioeconomic level. We use unique data on two highly comparable societies - U.S. and Canada - to contrast each of these inequality dimensions.

METHODS

Data came from the 2002/2003 Joint Canada/U.S. Survey of Health. We calculated adjusted prevalence ratios (APRs) for obesity (compared to normal weight) by income quintile and education group separately for both nations and, between Canadians and Americans in the same income or education group.

RESULTS

In the U.S., every socioeconomic group except the college educated had significant excess prevalence of obesity. By contrast in Canada, only those with less than high school were worse off, suggesting that the shape of the socioeconomic gradient differs in the two countries. U.S. differentials between socioeconomic levels were also larger than in Canada (e.g., PR quintile 1 compared to quintile 5 was 1.82 in the U.S. [95 % CI: 1.52-2.19] but 1.45 in Canada [95 % CI: 1.10-1.91]). At the lower end of the socioeconomic gradient, obesity was more prevalent in the U.S. than in Canada.

CONCLUSIONS

Our results suggest there is variation between U.S. and Canada in different dimensions of socioeconomic inequalities in obesity. Future research should examine a broader set of nations and test whether specific policies or environmental exposures can explain these differences.

Factors associated with higher sitting time in general, chronic disease, and psychologically-distressed, adult populations: findings from the 45 & up study

This study examined factors associated with higher sitting time in general, chronic disease, and psychologically-distressed, adult populations (aged ≥45 years). A series of logistic regression models examined potential socio-demographic and health factors associated with higher sitting (≥6hrs/day) in adults from the 45 and Up Study (n = 227,187), including four separate subsamples for analysis comprising those who had ever had heart disease (n = 26,599), cancer (n = 36,381), diabetes (n = 19,550) or psychological distress (n = 48,334). Odds of higher sitting were significantly (p<.01) associated with a number of factors across these groups, with an effect size of ORs≥1.5 observed for the high-income ≥$70,000AUD, employed full-time and severe physical limitations demographics. Identification of key factors associated with higher sitting time in this population-based sample will assist development of broad-based, public health and targeted strategies to reduce sitting-time. In particular, those categorized as being high-income earners, full-time workers, as well as those with severe physical limitations need to be of priority, as higher sitting appears to be substantial across these groups.

The sedentary office: an expert statement on the growing case for change towards better health and productivity

An international group of experts convened to provide guidance for employers to promote the avoidance of prolonged periods of sedentary work. The set of recommendations was developed from the totality of the current evidence, including long-term epidemiological studies and interventional studies of getting workers to stand and/or move more frequently. The evidence was ranked in quality using the four levels of the American College of Sports Medicine. The derived guidance is as follows: for those occupations which are predominantly desk based, workers should aim to initially progress towards accumulating 2 h/day of standing and light activity (light walking) during working hours, eventually progressing to a total accumulation of 4 h/day (prorated to part-time hours). To achieve this, seated-based work should be regularly broken up with standing-based work, the use of sit-stand desks, or the taking of short active standing breaks. Along with other health promotion goals (improved nutrition, reducing alcohol, smoking and stress), companies should also promote among their staff that prolonged sitting, aggregated from work and in leisure time, may significantly and independently increase the risk of cardiometabolic diseases and premature mortality. It is appreciated that these recommendations should be interpreted in relation to the evidence from which they were derived, largely observational and retrospective studies, or short-term interventional studies showing acute cardiometabolic changes. While longer term intervention studies are required, the level of consistent evidence accumulated to date, and the public health context of rising chronic diseases, suggest initial guidelines are justified. We hope these guidelines stimulate future research, and that greater precision will be possible within future iterations.

Impact of physical activity interventions on anthropometric outcomes: systematic review and meta-analysis

Considerable research has tested physical activity (PA) interventions to prevent and treat overweight and obesity. This comprehensive meta-analysis synthesized the anthropometric effects of supervised exercise interventions and motivational interventions to increase PA. Eligible intervention studies included healthy participants with reported anthropometric outcomes [e.g., body mass index (BMI)]. Extensive searching located 54,642 potentially eligible studies. We included data from 535 supervised exercise and 283 motivational interventions in our syntheses, which used random-effects analyses. Exploratory moderator analyses used meta-analytic analogues of ANOVA and regression. We synthesized data from 20,494 participants in supervised exercise and 94,711 undergoing motivational interventions. The overall mean effect sizes (ES, d) for treatment versus control groups in supervised exercise interventions were 0.20 (treatment vs. control within-group comparison) and 0.22 (between-group comparison). The ES of 0.22 represents a post-intervention BMI of 26.7 kg/m(2) for treatment participants relative to 27.7 kg/m(2) for controls. The corresponding mean ES for motivational interventions was significantly smaller (d = 0.09 for between group, d = 0.10 for treatment vs. control within-group). Control group within-group comparisons revealed slightly worsening anthropometric outcomes during study participation (d = -0.03 to -0.04). Moderator analyses identified potential variables for future research. These findings document significant improvements in anthropometric effects from both supervised exercise and motivational interventions.

Physical factors, personal characteristics, and substance use: associations with obesity

BACKGROUND

Because obesity has become a major public health problem, attention to a range of its predictors is needed. This study examined the association of physical factors, personal characteristics, and substance use with obesity in a sample (N = 815) of African American and Puerto Rican young adults with a mean age of 32.

METHODS

Body mass index (BMI) was calculated to assess obesity. Bivariate and multivariate logistic regression analyses were conducted.

RESULTS

Bivariate analyses showed that protective factors such as physical activity (adjusted odds ratio [AOR] = .82, 95% confidence interval [CI] = .74-.91), healthy diet (AOR = .96, 95% CI = .93-.99), self-control (AOR = .93, 95% CI = .87-.98), and life satisfaction (AOR = .97, 95% CI = .95-.99) were associated with a reduced probability of being obese. Marijuana use was also associated with a decreased probability of obesity (AOR = .89, 95% CI = .80-.99), but was not considered a protective factor. Risk factors such as short sleep duration (AOR = 1.70, 95% CI = 1.24-2.33) and depressive mood (AOR = 1.05, 95% CI = 1.01-1.09) were associated with an increased probability of being obese.

CONCLUSIONS

For African Americans and Puerto Ricans, programs to treat obesity should focus on increasing sleep, physical activity, and life satisfaction.

Does physical activity influence the relationship between low back pain and obesity?

BACKGROUND CONTEXT

Evidence supporting an association between obesity and low back pain (LBP) continues to grow; yet little is known about the cause and effect of this relationship. Even less is known about the mechanisms linking the two. Physical activity is a logical suspect, but no study has demonstrated its role.

PURPOSE

This study was designed to examine the interrelationship between physical activity, obesity, and LBP. The specific aims were to determine if obesity is a risk factor for LBP in the U.S. population, measure the strength of any observed association, and evaluate the role of physical activity in modulating this association.

STUDY DESIGN/SETTING

A cross-sectional U.S. population-based study.

PATIENT SAMPLE

A cohort of 6,796 adults from the 2003-2004 National Health and Nutrition Examination Survey.

OUTCOME MEASURES

Demographic information, an in-depth health questionnaire, physical examination details, and 7-day free-living physical activity monitoring using accelerometry (ActiGraph AM-7164; ActiGraph, Pensacola, FL, USA).

METHODS

LBP status was determined by questionnaire response. Body mass index (BMI) was calculated during physical examination and divided here into four groups (normal weight <25, overweight 25-30, obese 31-35, and ultraobese 36+). Summary measures of physical activity were computed based on intensity cutoffs, percentile intensities, and bout. Demographics, social history, and comorbid health conditions were used to build adjusted weighted logistic regression models constructed using Akaike Information Criterion. All displayed estimates are significant at level <.05. No external funding was received to support this study. None of the authors report conflicts of interest directly related to the specific subject matter of this manuscript.

RESULTS

In the U.S. population, the risk of low LBP increases in step with BMI from 2.9% for normal BMI (20-25) to 5.2% for overweight (26-30), 7.7% for obese (31-35), and 11.6% for ultraobese (36+). Smoking is consistently the strongest predictor of LBP across the BMI spectrum (odds ratio 1.6-2.9). Physical activity also modulates these risks. In the overall model, the best physical activity predictors of LBP are in the moderate and high intensity ranges with small effects (odds ratio 0.98 and 0.996 per standard deviation increase, respectively). When broken down by BMI, time spent in sedentary and moderate activity ranges demonstrate more robust influences on LBP status in the overweight, obese, and ultraobese groups.

CONCLUSIONS

Increased BMI is a risk factor for back pain in Americans. More important, the role of physical activity in mitigating back pain risk is shown to be of greater consequence in the overweight and obese populations.

How is post-industrial decline associated with the geography of physical activity? Evidence from the Health Survey for England

In recent decades, the prevalence of physical activity has declined considerably in many developed countries, which has been related to rising levels of obesity and several weight-related medical conditions, such as coronary heart disease. There is evidence that areas exhibiting particularly low levels of physical activity have undergone a strong transition away from employment in physically demanding occupations. It is proposed that such processes of deindustrialisation may be causally linked to unexplained geographical disparities in physical activity. This study investigates how geographical variations in deindustrialisation are associated with current levels of physical activity across different activity domains and relevant macro-economic time periods in England. The analysis includes data on 27,414 adults from the Health Survey for England 2006 and 2008 who reported total, occupational, domestic, recreational and walking activity. Based on employment change in industries associated with heavy manual work, a local measurement of industrial decline was developed, covering the period 1841–2001. We applied a multilevel modelling approach to study associations between industrial decline and physical activity. Results indicate that the process of deindustrialisation appears to be associated with patterns of physical activity and that this is independent of household income. The effects observed were generally similar for men and women. However, the nature of the association differed across areas, time periods and employment types; in particular, residents of districts characterised by a history of manufacturing and mining employment had increased odds of reporting low activity levels. We conclude that post-industrial change may be a factor in explaining present-day variations in physical activity, emphasising the plausible impact of inherited cultures and regional identities on health related behaviours.

•

This study is the first to link different physical activity domains to the historical context of deindustrialisation

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We found some evidence that processes of deindustrialisation may be associated with lower physical activity

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Lower overall activity was generally seen in areas with historically high employment then decline in manufacturing and mining

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Findings suggest cultures of non-participation in physical activity may persist in areas experiencing losses in manual jobs

Energy balance and obesity: a UK perspective on the gluttonyv.sloth debate

Obesity in the UK was assumed to have developed against a population decline in physical activity, with health messages focused on diet and exercise prevention strategies. Doubly-labelled water (DLW) studies of energy expenditure have indicated the alternative scenario that the increased obesity prevalence reflects excessive food energy intake with physical activity levels unchanged. This analysis is questionable, deriving in part from a weakness of the DLW methodology in identifying changing physical activity levels within populations of increasing body weight. This has resulted in an underestimation of the reduction in physical activity in the overweight and obese, as revealed by direct studies of such behaviour. Furthermore, a close examination of food energy supply, household food purchases and individual food energy consumption since 1955, in relation to likely estimates of current intakes indicated by simple modelling of predicted energy expenditure, identifies: (a) food energy supply as markedly overestimating energy intakes; (b) individual food energy consumption as markedly underestimating energy intakes; and (c) household food purchase data as the closest match to predicted current food energy intakes. Energy intakes indicated by this latter method have fallen by between 20 to 30 %, suggesting comparable falls in physical activity. Although unequivocal evidence for a matching UK trend in falling physical activity is limited, as is evidence that obesity follows reductions in physical activity, such a link has been recently suggested in a large prospective study in adolescents. Thus, for the UK, obesity has developed within a ‘move less–eat somewhat less but still too much’ scenario. A focus on both diet and exercise should remain the appropriate public health policy.

Fat free mass explains the relationship between stunting and energy expenditure in urban Mexican Maya children

BACKGROUND

Childhood stunting has been associated with an increased risk of obesity in adulthood, but the causes are unclear. This study hypothesizes that stunting significantly reduces both resting and activity energy expenditure.

AIM

To assess and describe energy expenditure of low socio-economic Maya children and to determine whether stunting is independently related to energy expenditure after controlling for lean mass.

SUBJECTS AND METHODS

Thirty-three urban Maya children, 17 boys, aged 7-9 years, living in Merida, Mexico, were measured for height, weight and bioelectrical impedance analysis (BIA). Body composition was estimated from BIA. Energy expenditure was measured for one week using the Actiheart (combined heart rate and accelerometer).

RESULTS

Stunting (height-for-age below the 5(th) percentile of NHANES III based references) affected 35% of these physically active children. Using multiple linear regression analysis, greater lean body mass predicted higher resting and activity energy expenditure. Stature was not a significant predictor of resting energy expenditure. A lower height-for-age z-score, but not stunting as a categorical variable, significantly predicted lower activity energy expenditure.

CONCLUSION

The hypothesis that stunting reduces total energy expenditure (resting + active) in children is not supported. Rather, children with shorter stature and less lean body mass have lower total energy expenditure. Complex interactions between body size, body composition, and metabolic activity appear to elevate the risk for later life obesity in these Maya children.

Physical activity attitudes, intentions and behaviour among 18-25 year olds: a mixed method study

BACKGROUND

Young people (18-25 years) during the adolescence/adulthood transition are vulnerable to weight gain and notoriously hard to reach. Despite increased levels of overweight/obesity in this age group, physical activity behaviour, a major contributor to obesity, is poorly understood. The purpose of this study was to explore physical activity (PA) behaviour among 18-25 year olds with influential factors including attitudes, motivators and barriers.

METHODS

An explanatory mixed method study design, based on health Behaviour Change Theories was used. Those at university/college and in the community, including those Not in Education, Employment or Training (NEET) were included. An initial self reported quantitative questionnaire survey underpinned by the Theory of Planned Behaviour and Social Cognitive Theory was conducted. 1313 questionnaires were analysed. Results from this were incorporated into a qualitative phase also grounded in these theories. Seven focus groups were conducted among similar young people, varying in education and socioeconomic status. Exploratory univariate analysis was followed by multi staged modelling to analyse the quantitative data. 'Framework Analysis' was used to analyse the focus groups.

RESULTS

Only 28% of 18-25 year olds achieved recommended levels of PA which decreased with age. Self-reported overweight/obesity prevalence was 22%, increasing with age, particularly in males. Based on the statistical modelling, positive attitudes toward PA were strong predictors of physical activity associated with being physically active and less sedentary. However, strong intentions to do exercise, was not associated with actual behaviour. Interactive discussions through focus groups unravelled attitudes and barriers influencing PA behaviour. Doing PA to feel good and to enjoy themselves was more important for young people than the common assumptions of 'winning' and 'pleasing others'. Further this age group saw traditional health promotion messages as 'empty' and 'fear of their future health' was not a motivating factor to change current behaviour.

CONCLUSION

18-25 year olds are a difficult group to reach and have low levels of PA. Factors such as, 'enjoyment', 'appearance 'and 'feeling good' were deemed important by this specific age group. A targeted intervention incorporating these crucial elements should be developed to improve and sustain PA levels.

A physically active occupation does not result in compensatory inactivity during out-of-work hours

AIM

To examine differences in non-occupational physical activity behaviour in workers who engage in high and low occupational physical activity.

DESIGN

Cross-sectional survey of 112 otherwise comparable volunteers in active (56 walking postal delivery workers) or inactive (56 administrative postal workers) occupations in Glasgow (Scotland) in 2007.

METHODS

Twenty four-hour physical activity (steps and time standing, walking and sedentary) patterns were measured using activPAL™ for seven days. Comparisons were made during 8-hour work-shifts, during non-work hours on work-days and during the 2 non-work days.

RESULTS

Age and body mass index of delivery and office staff, respectively, were (means (SD)) 38 (9) years versus 40 (7) years and 26.3 (3) kg m(-2) versus 27.4 (4) kg m(-2). Delivery staff spent substantially longer time than office staff upright (6.0 (1.1) h versus 3.9 (1.5) h) and walking (3.1 (0.7) h versus 1.6 (0.7) h) and amassed more steps (16,035 (4264) versus 6709 (2808)) during 8-hour work-shifts and over 24h on work days. During non-work hours of work-days and during non-work days, there were no significant differences in physical activity between the groups. The results were unchanged when the 15 women were excluded.

CONCLUSION

Having a more active occupation is not associated with more inactivity during non-work hours.