Obesity prevention programs can lower kids’ blood pressure, even if they don’t reduce body fat

One of the serious health consequences of obesity is elevated blood pressure (BP), a particular problem in children because research has found that high BP in children usually follows them into adulthood, carrying with it a wide range of possible negative consequences.Even modest elevations in the BP of adolescents, according to recent research, can pose cardiovascular problems later in life.A systematic review and meta-analysis of published studies of the effect of child obesity intervention programs on blood pressure has found that whether such programs prevented obesity or not, many of them reduced BP in children. It also found that the most effective programs in this regard promoted both healthy eating and physical activity.The study, one of the first of its kind, “Effect of Childhood Obesity Prevention Programs on BP: A Systematic Review and Meta-Analysis,” was led by epidemiologist Youfa Wang, MD, PhD, of the University at Buffalo and conducted by researchers from Johns Hopkins University, UB and other institutions.It was published online in the journal Circulation on Feb. 19, 2014 in advance of print publication.Wang said, “Of the 28 obesity interventions with complete data that we analyzed, 13 (46 percent) had a favorable effect on both adiposity and BP and 11 interventions (39 percent) had a significant effect on the reduction of BP, even if they did not affect adiposity. “It is important to identify obesity intervention programs that can help children develop healthy lifestyles and keep BP at an optimal level,” he says, “because these programs help them avoid many long-term health consequences.”Wang’s research team, now based at UB, is working on projects in the U.S. and abroad funded by the National Institutes of Health (NIH) that aim to assess the additional benefits of obesity prevention programs for children and to develop the most effective programs possible.The team also is using transnational comparison studies to analyze factors suspected of contributing to the global obesity epidemic.Story Source:The above story is based on materials provided by University at Buffalo. The original article was written by Pat Donovan. Note: Materials may be edited for content and length.

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Wide range of differences, mostly unseen, among humans

Sep. 5, 2013 — No two human beings are the same. Although we all possess the same genes, our genetic code varies in many places. And since genes provide the blueprint for all proteins, these variants usually result in numerous differences in protein function. But what impact does this diversity have? Bioinformatics researchers at Rutgers University and the Technische Universität München (TUM) have investigated how protein function is affected by changes at the DNA level. Their findings bring new clarity to the wide range of variants, many of which disturb protein function but have no discernible health effect, and highlight especially the role of rare variants in differentiating individuals from their neighbors.The slightest changes in human DNA can result in an incorrect amino acid being incorporated into a protein. In some cases, all it takes is for a single base to be substituted in a person’s DNA, a variant known as a single nucleotide polymorphism (SNP). “Many of these point mutations have no impact on human health. However, of the roughly 10,000 ‘missense’ SNPs in the human genome — that is, SNPs affecting the protein sequence — at least a fifth can change the function of the protein,” explains Prof. …

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Personality effects on fertility

Aug. 21, 2013 — A new study from IIASA population researchers finds a link between men’s and women’s personalities and the likelihood that they will have children.Men with neurotic personality traits are having fewer children compared to previous generations, according to a new study published in the European Journal of Personality. The study examined the effect of personality on how likely a person is to have children, using extensive survey and birth registry data from Norway. It also found that men who are extraverted and open tend to have more children, while women who rank as conscientious on personality tests tend to have fewer children, although these findings were constant across generations.The study could have important implications for population dynamics at a time when fertility rates across developed countries have fallen to below replacement rates. Personality effects may be one factor contributing to the decline of fertility rates in Europe, says IIASA’s Vegard Skirbekk, who led the study, but they have not previously been studied in detail. Population changes are an important factor for projecting future changes in sustainability, climate, energy, and food security, IIASA’s core research areas.In particular, Skirbekk notes the decline in childbearing among neurotic men — neurotic meaning individuals who tend to be moody and emotional. The study found that the effect only applies for men born after 1957. Skirbekk says that the change in these men’s fertility could be due to new norms in having children, for example that couples today wait longer to have children, and couples tend to test each other out more before committing to raising children together.The study was made possible by Norway’s very detailed birth records and an integrated personality survey, which allowed the researchers to examine the connections between both female and male fertility and personality. “For men, often you don’t know exactly how many children they have because information is not matched in the registries, but for Norway we have very exact information” says Skirbekk.While the study only considers Norway, Skirbekk says that the findings likely apply more widely. “Norway is a leader country in terms of family dynamics,” says Skirbekk, “Many trends that have been observed first in Norway — increasing cohabitation, divorce rates, and later marriage, for example — have then been observed later in many other parts of the world. …

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New way to measure cumulative effect of head hits in football

July 18, 2013 — Scientists at Wake Forest Baptist Medical Center have developed a new way to measure the cumulative effect of impacts to the head incurred by football players.The metric, called Risk Weighted Cumulative Exposure (RWE), can capture players’ exposure to the risk of concussion over the course of a football season by measuring the frequency and magnitude of all impacts, said senior author of the study Joel Stitzel, Ph.D., chair of biomedical engineering at Wake Forest Baptist and associate head of the Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences.The study is published in the current online edition of the Annals of Biomedical Engineering.Based on data gathered throughout a season of high school football games and practices, the researchers used RWE to measure the cumulative risk of injury due to linear and rotational acceleration separately, as well as the combined probability of injury associated with both.”This metric gives us a way to look at a large number of players and the hits they’ve incurred while playing football,” Stitzel said. “We know that young players are constantly experiencing low-level hits that don’t cause visible injury, but there hasn’t been a good way to measure the associated risk of concussion.”Concussion is the most common sports-related head injury, with football players having the highest rate among high school athletes, according to the study. It is estimated that nearly 1.1 million students play high school football in the United States. However, research on the biomechanics of football-related head impacts traditionally has concentrated on the collegiate level rather than on the high school level.With such a large number of players in the sport, it is critical to understand the risk associated with different levels of impact and accurately estimate cumulative concussion risk over the course of a practice, game, season or lifetime, Stitzel said.In the Wake Forest Baptist study, the researchers measured the head impact exposure in 40 high school football players by using sensors placed in their helmets to record linear and rotational acceleration. A total of 16,502 impacts were collected over the course of one football season and the data were analyzed as a group and as individual players.Impacts were weighted according to the associated risk from linear acceleration and rotational acceleration alone, as well as to the combined probability of injury associated with both. This is an improved method of capturing the cumulative effects from each impact because it accounts for nonlinear relationships between impact magnitude and the associated risk of injury, Stitzel said.”All hits involve both linear and rotational acceleration, but rotation coveys the idea that your head is pivoting about the neck whereas linear acceleration is experienced from a direct blow in more of a straight line through the center of mass of the head,” Stitzel said.The median impact for each player ranged from 15.2 to 27.0 g, with an average value of 21.7 g, which shows the wide variability in the force of impacts.The study found that impact frequency was greater during games (15.5) than during practices (9.4). However, overall exposure over the course of the season was greater during practices.This information may help teams reduce exposure to head impacts during practices by teaching proper tackling techniques that could reduce exposure to impacts that may result in a higher concussion rate, the researchers reported.Additionally, the study found a wide variation in player exposure within the team, with a 22-fold variation in the exposure per impact for practices and a 47-fold variation in the exposure for impact for games.Studies like this are vital to understanding the biomechanical basis of head injuries related to football, Stitzel said. The metric fully captures a player’s exposure over the course of the season and will be used in conjunction with other pre- and post-season evaluations, including MRI and neurological tests conducted as part of this study. The research team hopes that this work may ultimately improve helmet safety and design to make football a safer sport.The study was funded by the Childress Institute for Pediatric Trauma.Co-authors are Jillian Urban, M.S., Elizabeth Davenport, B.S., Adam Golman, M.S., Joseph Maldjian, M.D., Christopher Whitlow, M.D., and Alexander Powers, M.D., of Wake Forest Baptist.

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Air pollution responsible for more than 2 million deaths worldwide each year, experts estimate

July 12, 2013 — More than two million deaths occur worldwide each year as a direct result of human-caused outdoor air pollution, a new study has found.In addition, while it has been suggested that a changing climate can exacerbate the effects of air pollution and increase death rates, the study shows that this has a minimal effect and only accounts for a small proportion of current deaths related to air pollution.The study, which has been published today, 12 July, in IOP Publishing’s journal Environmental Research Letters, estimates that around 470,000 people die each year because of human-caused increases in ozone.It also estimates that around 2.1 million deaths are caused each year by human-caused increases in fine particulate matter (PM2.5) ? tiny particles suspended in the air that can penetrate deep into the lungs, causing cancer and other respiratory disease.Co-author of the study, Jason West, from the University of North Carolina, said: “Our estimates make outdoor air pollution among the most important environmental risk factors for health. Many of these deaths are estimated to occur in East Asia and South Asia, where population is high and air pollution is severe.”According to the study, the number of these deaths that can be attributed to changes in the climate since the industrial era is, however, relatively small. It estimates that a changing climate results in 1500 deaths due to ozone and 2200 deaths related to PM2.5 each year.Climate change affects air quality in many ways, possibly leading to local increases or decreases in air pollution. For instance, temperature and humidity can change the reaction rates which determine the formation or lifetime of a pollutant, and rainfall can determine the time that pollutants can accumulate.Higher temperatures can also increase the emissions of organic compounds from trees, which can then react in the atmosphere to form ozone and particulate matter.”Very few studies have attempted to estimate the effects of past climate change on air quality and health. We found that the effects of past climate change are likely to be a very small component of the overall effect of air pollution,” continued West.In their study, the researchers used an ensemble of climate models to simulate the concentrations of ozone and PM2.5 in the years 2000 and 1850. A total of 14 models simulated levels of ozone and six models simulated levels of PM2.5.Previous epidemiological studies were then used to assess how the specific concentrations of air pollution from the climate models related to current global mortality rates.The researchers’ results were comparable to previous studies that have analysed air pollution and mortality; however, there was some variation depending on which climate model was used.”We have also found that there is significant uncertainty based on the spread among different atmospheric models. This would caution against using a single model in the future, as some studies have done,” continued West.

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