Canaries in the coal mine: a cross-species analysis of the plurality of obesity epidemics
Source: Proceedings of the Royal Society
A dramatic rise in obesity has occurred among humans within the last several decades. Little is known about whether similar increases in obesity have occurred in animals inhabiting human-influenced environments. We examined samples collectively consisting of over 20 000 animals from 24 populations (12 divided separately into males and females) of animals representing eight species living with or around humans in industrialized societies. In all populations, the estimated coefficient for the trend of body weight over time was positive (i.e. increasing). The probability of all trends being in the same direction by chance is 1.2 × 10−7. Surprisingly, we find that over the past several decades, average mid-life body weights have risen among primates and rodents living in research colonies, as well as among feral rodents and domestic dogs and cats. The consistency of these findings among animals living in varying environments, suggests the intriguing possibility that the aetiology of increasing body weight may involve several as-of-yet unidentified and/or poorly understood factors (e.g. viral pathogens, epigenetic factors). This finding may eventually enhance the discovery and fuller elucidation of other factors that have contributed to the recent rise in obesity rates.
Public Agrees on Obesity’s Impact, Not Government’s Role
Source: Pew Research Center for the People & the Press
Most Americans (69%) see obesity as a very serious public health problem, substantially more than the percentages viewing alcohol abuse, cigarette smoking and AIDS in the same terms. In addition, a broad majority believes that obesity is not just a problem that affects individuals: 63% say obesity has consequences for society beyond the personal impact on individuals. Just 31% say it impacts the individuals who are obese but not society more broadly.
Yet, the public has mixed opinions about what, if anything, the government should do about the issue. A 54% majority does not want the government to play a significant role in reducing obesity, while 42% say the government should play a significant role. And while some proposals for reducing obesity draw broad support, others are decidedly unpopular.
New ACC/AHA Prevention Guidelines Address Blood Cholesterol, Obesity, Healthy Living and Risk Assessment
New ACC/AHA Prevention Guidelines Address Blood Cholesterol, Obesity, Healthy Living and Risk Assessment
Source: American College of Cardiology/American Heart Association
The ACC and the American Heart Association (AHA), in collaboration with the National Heart, Lung, and Blood Institute (NHLBI) and other specialty societies, have released four guidelines focused on the assessment of cardiovascular risk, lifestyle modifications to reduce cardiovascular risk and management of elevated blood cholesterol and body weight in adults.
These four prevention guidelines released Nov. 12 were among five initially commissioned by NHLBI starting in 2008 and transitioned to the ACC and AHA in June 2013 as part of a collaborative arrangement to facilitate their completion and publication. A fifth guideline addressing hypertension will be initiated in early 2014. Each provides important updated guidance for primary care providers, nurses, pharmacists and specialty medicine providers on how best to manage care of individuals at risk for cardiovascular-related diseases based on the latest scientific evidence.
Fighting Obesity in the United States with State Legislation
Source: RAND Corporation
Obesity is a problem of epidemic proportions in the U.S. There is a role for government involvement to reduce and prevent this public health problem of obesity. Strategies for obesity prevention are moving away from focusing on the individual alone and towards an ecological model to address environmental and societal influences on behavior. Obesity prevention efforts are taking place at national, state and local levels. Since individual states have fiscal and legislative authority and regulatory powers for public health policy, this project will focus at the state level. Various states have already implemented nutrition standards for school meals, taxes on foods of low nutritional standards, or require weight-related assessments for children and adolescents. Given the need to address ecological factors and the complexities of the policy making process, “Does state legislation reduce and prevent obesity at the state level? If not, why?”
The study’s aims are to: (1) describe the landscape of obesity prevention legislation, including how legislation compares to research-based policy recommendations; (2) examine the association between obesity prevention legislation and obesity prevalence and other weight outcomes; (3) identify the process of how obesity prevention legislation are formulated and implemented, including factors that facilitate or hinder the process; and (4) suggest strategies to improve role of state legislation in preventing obesity.
Ancestral dichlorodiphenyltrichloroethane (DDT) exposure promotes epigenetic transgenerational inheritance of obesity
Ancestral environmental exposures to a variety of environmental factors and toxicants have been shown to promote the epigenetic transgenerational inheritance of adult onset disease. The present work examined the potential transgenerational actions of the insecticide dichlorodiphenyltrichloroethane (DDT) on obesity and associated disease.
Outbred gestating female rats were transiently exposed to a vehicle control or DDT and the F1 generation offspring bred to generate the F2 generation and F2 generation bred to generate the F3 generation. The F1 and F3 generation control and DDT lineage rats were aged and various pathologies investigated. The F3 generation male sperm were collected to investigate methylation between the control and DDT lineage male sperm.
The F1 generation offspring (directly exposed as a fetus) derived from the F0 generation exposed gestating female rats were not found to develop obesity. The F1 generation DDT lineage animals did develop kidney disease, prostate disease, ovary disease and tumor development as adults. Interestingly, the F3 generation (great grand-offspring) had over 50% of males and females develop obesity. Several transgenerational diseases previously shown to be associated with metabolic syndrome and obesity were observed in the testis, ovary and kidney. The transgenerational transmission of disease was through both female (egg) and male (sperm) germlines. F3 generation sperm epimutations, differential DNA methylation regions (DMR), induced by DDT were identified. A number of the genes associated with the DMR have previously been shown to be associated with obesity.
Observations indicate ancestral exposure to DDT can promote obesity and associated disease transgenerationally. The etiology of disease such as obesity may be in part due to environmentally induced epigenetic transgenerational inheritance.
See: Researchers Link DDT, Obesity (Science Daily)
Prevalence of Obesity Among Adults: United States, 2011–2012
Source: National Center for Health Statistics
Data from the National Health and Nutrition Examination Survey, 2011–2012
- More than one-third (34.9%) of adults were obese in 2011–2012.
- In 2011–2012, the prevalence of obesity was higher among middle-aged adults (39.5%) than among younger (30.3%) or older (35.4%) adults.
- The overall prevalence of obesity did not differ between men and women in 2011–2012. Among non-Hispanic black adults, however, 56.6% of women were obese compared with 37.1% of men.
- In 2011–2012, the prevalence of obesity was higher among non-Hispanic black (47.8%), Hispanic (42.5%), and non-Hispanic white (32.6%) adults than among non-Hispanic Asian adults (10.8%).
- The prevalence of obesity among adults did not change between 2009–2010 and 2011–2012.
Debit card payment systems are known to induce more frivolous purchases in adults, but their impact on children is unknown.
Design and Methods
Using a national survey of 2,314 public school students in the United States, food purchases in schools with debit-only systems to those in schools with both debit and cash options are compared.
Students in debit and cash schools purchase more fresh fruit and vegetables and fewer total calories.
Payment systems with cash options have a lower purchase incidence of less healthy foods and higher purchase incidence of more healthy foods.
Pregnancy Weight Gain and Childhood Body Weight: A Within-Family Comparison
Source: PLoS Medicine
Excessive pregnancy weight gain is associated with obesity in the offspring, but this relationship may be confounded by genetic and other shared influences. We aimed to examine the association of pregnancy weight gain with body mass index (BMI) in the offspring, using a within-family design to minimize confounding.
Methods and Findings
In this population-based cohort study, we matched records of all live births in Arkansas with state-mandated data on childhood BMI collected in public schools (from August 18, 2003 to June 2, 2011). The cohort included 42,133 women who had more than one singleton pregnancy and their 91,045 offspring. We examined how differences in weight gain that occurred during two or more pregnancies for each woman predicted her children’s BMI and odds ratio (OR) of being overweight or obese (BMI≥85th percentile) at a mean age of 11.9 years, using a within-family design. For every additional kg of pregnancy weight gain, childhood BMI increased by 0.0220 (95% CI 0.0134–0.0306, p<0.0001) and the OR of overweight/obesity increased by 1.007 (CI 1.003–1.012, p = 0.0008). Variations in pregnancy weight gain accounted for a 0.43 kg/m2 difference in childhood BMI. After adjustment for birth weight, the association of pregnancy weight gain with childhood BMI was attenuated but remained statistically significant (0.0143 kg/m2 per kg of pregnancy weight gain, CI 0.0057–0.0229, p = 0.0007).
High pregnancy weight gain is associated with increased body weight of the offspring in childhood, and this effect is only partially mediated through higher birth weight. Translation of these findings to public health obesity prevention requires additional study.
Leveraging Action to Support Dissemination of Pregnancy Weight Gain Guidelines – Workshop Summary
Source: Institute of Medicine
Along with recommending revised pregnancy weight gain guidelines, the 2009 IOM and National Research Council (NRC) report, Weight Gain During Pregnancy: Reexamining the Guidelines, identified evidence that preconception counseling and certain practices, such as charting weight gain during pregnancy, can lead to improved choices concerning nutrition and physical activity. However, many women still do not receive adequate pre- or post-conception advice about weight and pregnancy weight gain. Many women and health professionals remain unaware of the recommended pregnancy weight guidelines and even those women who are aware of the guidelines may find it difficult to get informed guidance that can help them achieve those guidelines.
On March 1, 2013, the IOM and NRC held a workshop to discuss communication and implementation of recommended guidelines for healthy pregnancy weight gain. The workshop featured a range of products for dissemination, panel discussions on ways to facilitate and support women’s efforts to achieve a healthy weight pre- and post-pregnancy, a discussion on how to put the weight gain guidelines into action, and a presentation on innovative ways to reach women and implement change. This document summarizes the workshop.
Performance Standards for Restaurants: A New Approach to Addressing the Obesity Epidemic
Source: RAND Corporation
Americans rely on foods prepared away from home for an estimated 33 percent of caloric intake. Most restaurants serve foods that have excessive calories, fat, sugar, and salt while omitting fruit, vegetables, and whole grains, the very foods needed to meet the Dietary Guidelines for Americans. In an effort to offer guidance to restaurants and communities as they seek to promote healthy food choices, a conference was held on March 14–15, 2012, in Santa Monica, California, that was funded, in part, by the National Institutes of Health/National Institute of Minority Health and Health Disparities and was organized by the RAND Corporation. A group of 38 national experts in nutrition and public health met to develop performance standards that could guide restaurants toward facilitating healthier choices among consumers.
The guidelines are based on the best available science, while also considering feasibility and acceptability. They recommend limiting a single meal to 700 calories or less for adults and 600 calories or less for children. Adult meals should include at least 1.5 cups of fruits or vegetables, less than 10 percent of calories from saturated fat, less than 770 mg of sodium, and less than 35 percent of calories from sugars. Children’s meals should include at least 0.5 cup of fruits or vegetables. Neither meal should include a sugar-sweetened beverage. In addition, the expert panel developed common-sense guidelines discouraging serving practices that increase caloric consumption or undermine a nutritious diet.
Local communities or states could develop and implement certification programs to evaluate adherence to these guidelines on a voluntary or mandatory basis. For example, restaurants could be certified as “healthier” by adopting enough of these guidelines to meet a specified threshold. While offering healthier choices may improve dietary quality, studies are needed to evaluate the economic impact on businesses that adopt them and their effectiveness in reducing caloric intake among diners.
CDC releases 2012 School Health Policies and Practices Study results
Source: Centers for Disease Control and Prevention
School districts nationwide are showing improvements in measures related to nutritional policies, physical education and tobacco policies, according to the 2012 School Health Policies and Practices Study (SHPPS). SHPPS is the largest and most comprehensive survey to assess school health policies.
Key findings include:
- The percentage of school districts that allowed soft drink companies to advertise soft drinks on school grounds decreased from 46.6 percent in 2006 to 33.5 percent in 2012.
- Between 2006 and 2012, the percentage of districts that required schools to prohibit offering junk food in vending machines increased from 29.8 percent to 43.4 percent.
- Between 2006 and 2012, the percentage of districts with food procurement contracts that addressed nutritional standards for foods that can be purchased separately from the school breakfast or lunch increased from 55.1 percent to 73.5 percent.
- Between 2000 and 2012, the percentage of districts that made information available to families on the nutrition and caloric content of foods available to students increased from 35.3 percent to 52.7 percent.
Physical education/physical activity:
- The percentage of school districts that required elementary schools to teach physical education increased from 82.6 percent in 2000 to 93.6 percent in 2012.
- More than half of school districts (61.6 percent) had a formal agreement, such as a memorandum of agreement or understanding, between the school district and another public or private entity for shared use of school or community property. Among those districts, more than half had agreements with a local youth organization (e.g., the YMCA, Boys or Girls Clubs, or the Boy Scouts or Girl Scouts) or a local parks or recreation department.
- The percentage of districts with policies that prohibited all tobacco use during any school-related activity increased from 46.7 percent in 2000 to 67.5 percent in 2012.
Factors Predicting Physical Activity Among Children With Special Needs
Source: Preventing Chronic Disease
Obesity is especially prevalent among children with special needs. Both lack of physical activity and unhealthful eating are major contributing factors. The objective of our study was to investigate barriers to physical activity among these children.
We surveyed parents of the 171 children attending Vista Del Mar School in Los Angeles, a nonprofit school serving a socioeconomically diverse group of children with special needs from kindergarten through 12th grade. Parents were asked about their child’s and their own physical activity habits, barriers to their child’s exercise, and demographics. The response rate was 67%. Multivariate logistic regression was used to examine predictors of children being physically active at least 3 hours per week.
Parents reported that 45% of the children were diagnosed with attention deficit hyperactivity disorder, 38% with autism, and 34% with learning disabilities; 47% of children and 56% of parents were physically active less than 3 hours per week. The top barriers to physical activity were reported as child’s lack of interest (43%), lack of developmentally appropriate programs (33%), too many behavioral problems (32%), and parents’ lack of time (29%). However, child’s lack of interest was the only parent-reported barrier independently associated with children’s physical activity. Meanwhile, children whose parents were physically active at least 3 hours per week were 4.2 times as likely to be physically active as children whose parents were less physically active (P = .01).
In this group of students with special needs, children’s physical activity was strongly associated with parental physical activity; parent-reported barriers may have had less direct effect. Further studies should examine the importance of parental physical activity among children with special needs.
F as in Fat: How Obesity Threatens America’s Future 2013
Source: Trust for America’s Health
After three decades of increases, adult obesity rates remained level in every state except for one, Arkansas, in the past year, according to F as in Fat: How Obesity Threatens America’s Future 2013, a report from the Trust for America’s Health (TFAH) and the Robert Wood Johnson Foundation (RWJF). The full report is available here. Visit http://www.FasinFat.org/ for interactives, graphs, charts and obesity rates for the states and nation going back decades.
Thirteen states now have adult obesity rates above 30 percent, 41 states have rates of at least 25 percent, and every state is above 20 percent, according to the report. In 1980, no state was above 15 percent; in 1991, no state was above 20 percent; in 2000, no state was above 25 percent; in 2007, only Mississippi was above 30 percent.
Since 2005, there has been some evidence that the rate of increase has been slowing. In 2005, every state but one experienced an increase in obesity rates; in 2008, rates increased in 37 states; in 2010, rates increased in 28 states; and in 2011, rates increased in 16 states.
Offering calories on restaurant websites might be particularly important for consumer meal planning, but the availability of and ease of accessing this information are unknown.
We assessed websites for the top 100 U.S. chain restaurants to determine the availability of and ease of access to calorie information as well as website design characteristics. We also examined potential predictors of calorie availability and ease of access.
Eighty-two percent of restaurants provided calorie information on their websites; 25% presented calories on a mobile-formatted website. On average, calories could be accessed in 2.35±0.99 clicks. About half of sites (51.2%) linked to calorie information via the homepage. Fewer than half had a separate section identifying healthful options (46.3%), or utilized interactive meal planning tools (35.4%). Quick service/fast casual, larger restaurants, and those with less expensive entrées and lower revenue were more likely to make calorie information available. There were no predictors of ease of access.
Calorie information is both available and largely accessible on the websites of America’s leading restaurants. It is unclear whether consumer behavior is affected by the variability in the presentation of calorie information.
Maternal obesity during pregnancy and premature mortality from cardiovascular event in adult offspring: follow-up of 1 323 275 person years
To determine whether maternal obesity during pregnancy is associated with increased mortality from cardiovascular events in adult offspring.
Record linkage cohort analysis.
Birth records from the Aberdeen Maternity and Neonatal databank linked to the General Register of Deaths, Scotland, and the Scottish Morbidity Record systems.
37 709 people with birth records from 1950 to present day.
outcome measures Death and hospital admissions for cardiovascular events up to 1 January 2012 in offspring aged 34-61. Maternal body mass index (BMI) was calculated from height and weight measured at the first antenatal visit. The effect of maternal obesity on outcomes in offspring was tested with time to event analysis with Cox proportional hazard regression to compare outcomes in offspring of mothers in underweight, overweight, or obese categories of BMI compared with offspring of women with normal BMI.
All cause mortality was increased in offspring of obese mothers (BMI >30) compared with mothers with normal BMI after adjustment for maternal age at delivery, socioeconomic status, sex of offspring, current age, birth weight, gestation at delivery, and gestation at measurement of BMI (hazard ratio 1.35, 95% confidence interval 1.17 to 1.55). In adjusted models, offspring of obese mothers also had an increased risk of hospital admission for a cardiovascular event (1.29, 1.06 to 1.57) compared with offspring of mothers with normal BMI. The offspring of overweight mothers also had a higher risk of adverse outcomes.
Maternal obesity is associated with an increased risk of premature death in adult offspring. As one in five women in the United Kingdom is obese at antenatal booking, strategies to optimise weight before pregnancy are urgently required.
Related editorial: Maternal obesity and heart disease in the offspring
Vital Signs: Obesity Among Low-Income, Preschool-Aged Children — United States, 2008–2011
Source: Morbidity and Mortality Weekly Report (CDC)
The prevalence of obesity among U.S. preschoolers has doubled in recent decades. Childhood obesity increases the risk for adult obesity and is associated with negative health consequences. Trends in the state-specific prevalence of obesity among low-income U.S. preschool children have not been examined since 2008. State-specific obesity prevalence surveillance helps determine the need for and impact of state and local obesity prevention strategies.
Measured weight and height data from approximately 11.6 million low-income children aged 2–4 years from 40 states, the District of Columbia, and two U.S. territories who participated in the Pediatric Nutrition Surveillance System during 2008–2011 were used to estimate state obesity prevalence. Obesity was defined as having an age- and sex-specific body mass index ≥95th percentile, according to the 2000 CDC growth charts. Logistic regression models adjusted for age, sex, and race/ethnicity were used to examine trends in the state-specific obesity prevalence.
During 2008–2011, statistically significant downward trends in obesity prevalence were observed in 18 states and the U.S. Virgin Islands. Florida, Georgia, Missouri, New Jersey, South Dakota, and the U.S. Virgin Islands had the largest absolute decreases in obesity prevalence, each with a decrease of ≥1 percentage point. Twenty states and Puerto Rico experienced no significant change, and obesity prevalence increased significantly in three states.
Conclusions and Implications for Public Health Practice:
Small but significant declines in obesity among low-income preschoolers were observed in 19 of 43 states/territories examined. Continued prevention efforts are needed to sustain and expand the implementation and evaluation of population-level interventions to prevent childhood obesity.
Evaluating Obesity Prevention Efforts: A Plan for Measuring Progress
Source: Institute of Medicine
Obesity poses one of the greatest public health challenges of the 21st century, creating serious health, economic, and social consequences for individuals and society. Despite acceleration in efforts to characterize, comprehend, and act on this problem, including implementation of preventive interventions, further understanding is needed on the progress and effectiveness of these interventions.
Evaluating Obesity Prevention Efforts develops a concise and actionable plan for measuring the nation’s progress in obesity prevention efforts–specifically, the success of policy and environmental strategies recommended in the 2012 IOM report Accelerating Progress in Obesity Prevention: Solving the Weight of the Nation. This book offers a framework that will provide guidance for systematic and routine planning, implementation, and evaluation of the advancement of obesity prevention efforts. This framework is for specific use with the goals and strategies from the 2012 report and can be used to assess the progress made in every community and throughout the country, with the ultimate goal of reducing the obesity epidemic. It offers potentially valuable guidance in improving the quality and effect of the actions being implemented.
The recommendations of Evaluating Obesity Prevention Efforts focus on efforts to increase the likelihood that actions taken to prevent obesity will be evaluated, that their progress in accelerating the prevention of obesity will be monitored, and that the most promising practices will be widely disseminated.
Perceived Weight Discrimination and Obesity
Source: PLoS ONE
Weight discrimination is prevalent in American society. Although associated consistently with psychological and economic outcomes, less is known about whether weight discrimination is associated with longitudinal changes in obesity. The objectives of this research are (1) to test whether weight discrimination is associated with risk of becoming obese (Body Mass Index≥30; BMI) by follow-up among those not obese at baseline, and (2) to test whether weight discrimination is associated with risk of remaining obese at follow-up among those already obese at baseline. Participants were drawn from the Health and Retirement Study, a nationally representative longitudinal survey of community-dwelling US residents. A total of 6,157 participants (58.6% female) completed the discrimination measure and had weight and height available from the 2006 and 2010 assessments. Participants who experienced weight discrimination were approximately 2.5 times more likely to become obese by follow-up (OR = 2.54, 95% CI = 1.58–4.08) and participants who were obese at baseline were three times more likely to remain obese at follow up (OR = 3.20, 95% CI = 2.06–4.97) than those who had not experienced such discrimination. These effects held when controlling for demographic factors (age, sex, ethnicity, education) and when baseline BMI was included as a covariate. These effects were also specific to weight discrimination; other forms of discrimination (e.g., sex, race) were unrelated to risk of obesity at follow-up. The present research demonstrates that, in addition to poorer mental health outcomes, weight discrimination has implications for obesity. Rather than motivating individuals to lose weight, weight discrimination increases risk for obesity.
Prevalence of physical activity and obesity in US counties, 2001-2011: a road map for action
Source: Institute for Health Metrics and Evaluation
Obesity and lack of physical activity are associated with several chronic conditions, such as heart disease and diabetes, increased health care costs, and premature death. Since different local governments have pursued different approaches to address both risks, levels of obesity and physical activity are likely to vary substantially across counties. To understand local trends in physical activity and obesity that would help identify successful and less successful strategies, researchers examined county-level changes in physical activity and obesity between 2001 and 2011.
The researchers used data from the Behavioral Risk Factor Surveillance System (BRFSS), a state-based random-digit telephone survey that covers the majority of United States counties, and the National Health and Nutrition Examination Survey (NHANES), a nationally representative sample of the US civilian noninstitutionalized population. They calculated body mass index (BMI) from self-reported weight and height in BRFSS, adjusting for self-reporting bias using NHANES, and calculated self-reported physical activity—both any physical activity and physical activity meeting recommended levels—from self-reported data in BRFSS. To generate estimates of obesity and physical activity prevalence for each county annually for 2001 to 2011, they used validated small area estimation methods.
Results showed that physical activity in US counties is increasing. Levels were generally higher in men than in women, but increases were greater in women than men, and counties in California, Florida, Georgia, and Kentucky reported the largest gains. However, this increase in level of activity was matched by an increase in obesity in almost all counties during the same time period. Increases in physical activity in counties were not shown to be strongly related to decreases in obesity – from 2001 to 2009, for every 1 percentage point increase in physical activity prevalence, obesity prevalence was 0.11 percentage points lower, controlling for changes in poverty, unemployment, number of doctors per 100,000 population, percent rural, and baseline levels of obesity.
While the increases in physical activity seen at the county level will have a positive impact on the health of Americans, these increases have a small impact on the prevalence of obesity. This means that other strategies are likely needed. Coordinated actions involving the health care and public health systems, non-governmental organizations, and food labeling, taxation, and incentive programs should be considered to curb the obesity epidemic and its burden.