In-utero exposure to magnetic fields associated with increased risk of obesity in childhood

ScienceDaily (July 27, 2012) — In-utero exposure to relatively high magnetic field levels was associated with a 69 percent increased risk of being obese or overweight during childhood compared to lower in-utero magnetic field levels, according to a Kaiser Permanente study that appears in the current online version of Nature's Scientific Reports.

See Also:Health & MedicineObesityPregnancy and ChildbirthDiet and Weight LossChildren's HealthAsthmaVitamin DReferenceOverweightBody mass indexNutrition and pregnancyBirth weight

Researchers conducted the prospective cohort study, in which participating women in Kaiser Permanente's Northern California region carried a meter measuring magnetic field levels during pregnancy and 733 of their children were followed up to 13 years, to collect clinically recorded information on growth patterns. On average, 33 weight measurements per child were collected.

Researchers noted a dose response relationship with increasing in-utero magnetic field levels being associated with further increased risk of obesity or being overweight. The observed association and supporting evidence provide the first epidemiologic findings that link increasing exposure to environmental magnetic fields, especially in-utero exposure, over the last few decades with the rapid rise in childhood obesity during the corresponding decades, according to the authors.

"Pregnancy is a critical developmental stage that is among the most vulnerable periods to environmental exposures," said De-Kun Li, MD, PhD, a perinatal epidemiologist with the Kaiser Permanente Northern California Division of Research in Oakland, Calif., and the lead author of the study. "These findings indicate that electromagnetic fields, from microwave ovens to countless wireless devices, may be contributing to childhood obesity risk. This finding could have implications for possibly reducing childhood obesity and better understanding the obesity epidemic. Like any scientific discoveries, the results need to be replicated by other studies."

After controlling for a child's age at each weight measurement, child gender, maternal age at delivery, pre-pregnancy BMI, race, education level, smoking during pregnancy and breastfeeding, researchers reported a 50 percent increase of participants being obese or overweight for medium in-utero levels (1.5-2.5 mG), and an 84 percent increased risk for high in-utero levels (more than 2.5mG). An mG, or milligauss, represents a unit of magnetic field level or strength as measured using a gaussmeter.

This study follows previous work from Dr. Li (and others) that showed electromagnetic fields may impact pregnancy outcomes and childhood diseases including asthma. Higher EMF levels have also been associated with diabetes in humans, being overweight and high glucose levels in animals, and ADHD in mice offspring, explained Dr. Li.

In the current study, among those children with longer follow-up time (to the end of the study), the observed association was stronger (2.35 times the risk of childhood obesity/overweight for in-utero MF level > 1.5 mG vs. ≤ 1.5 mG). Similarly, if the study only considered those who were persistently obese/overweight through childhood during the follow-up, the association was also much stronger (almost five-fold increased risk of obesity/overweight for in-utero MF level > 1.5 mG vs. < 1.5 mG).

"EMF exposure during pregnancy could impact the fetal development, including endocrine and metabolic systems, predisposing offspring to higher risk of obesity," Dr. Li said. He added that environmental impacts tend to be amplified during fetal development, both in terms of affecting multiple organ systems and having long-lasting changes to physiology, such as to the endocrine systems and hormone receptors.

Researchers examined maternal factors, prenatal factors, childhood factors, outcome measures and other factors that could be confounders. Among 18 factors examined, only family income and childhood habits of eating fruits and vegetables varied among the three maternal MF exposure groups. However, there was not a consistent pattern of MF exposure with family income: women with either low or high family income had lower MF exposure level than women with medium family income. Children eating more fruits and vegetables tended to have a mother who had higher MF exposure during pregnancy. There was no difference among the three MF exposure groups in the average number of weight measurements per child. The proportion of children who remained in the Kaiser Permanente Northern California integrated care delivery system at the end of the study (11 years and older) was almost identical in all three groups. None of the 18 factors examined could explain the observed association.

"Expectant mothers should take this new research into account, but they should not panic," said Ruth Shaber, MD, medical director of the Center for Healthcare Delivery at the Kaiser Permanente Care Management Institute. "We still have a lot more to learn about the impact of the environment on pregnancy and young children."

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Childhood obesity linked to cancer risk

ScienceDaily (July 23, 2012) — Parents are increasingly conscious of the dangers of childhood obesity. There is a growing recognition of health problems associated with extra pounds, including the risk of diabetes, heart disease, and joint and muscle pain.

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New research from Tel Aviv University has revealed another significant reason for children to maintain a healthy weight. Dr. Ari Shamiss and Dr. Adi Leiba of TAU's Sackler Faculty of Medicine and the Sheba Medical Center and his fellow researchers found that obesity in adolescence, defined as a Body Mass Index (BMI) in the 85th percentile and above, has a direct link to the incidence of urothelial (bladder and urinary tract) and colorectal cancers in adulthood. According to the American Heart Association, one in three children and teenagers are now considered overweight or obese.

Children above the 84th percentile in BMI have a 1.42% greater chance, representing a 50% higher risk, of developing urothelial or colorectal cancers in adulthood compared to those beneath it, explains Dr. Shamiss, whose research has been published in the journals Cancer Epidemiology, Biomarkers and Prevention and Obesity.

Understanding the connection

To examine the relationship between obesity and cancers, the researchers conducted a longitudinal study of a cohort of 1.1 million males in the Israeli Defense Forces. Their health information was gathered by the army, with a follow-up period of 18 years. When they controlled for factors such as year of birth and education, the researchers discovered a clear link between childhood BMI and those who were diagnosed with urothelial or colorectal cancers later in life.

While the researchers have so far uncovered risk in two different types of cancer, Dr. Shamiss believes that further research will reveal connections between childhood obesity and a wide range of other cancers, including pancreatic cancer, which he is currently researching.

These findings show a distinct need for more research in this field, he notes. "We need to examine the questions of whether obesity is a direct risk factor for cancer or a confounding factor for a genetic variation, for example," he explains, pointing out that basic research could help researchers to understand the connection between obesity and cancer on a deeper level.

The role of weight loss

One of the crucial questions, says Dr. Shamiss, is whether or not a successful weight loss attempt can reduce a child's risk of developing urothelial or colorectal cancer in adulthood. Their current sample looks at children who were obese and those who were of normal weight, but does not reveal whether weight loss makes a significant difference.

New research should focus on researching the pathogenetic link between obesity and cancer, and whether losing weight in adulthood could lower the risk, Dr. Shamiss says. Although healthcare professionals are already stressing the importance of preventing childhood obesity, this finding certainly adds to the urgency.

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Childhood Abuse Linked to Diabetes, Heart Disease in Middle-Aged Women

HealthDay – 1 hr 23 mins ago FRIDAY, July 20 (HealthDay News) -- Middle-aged women who suffered physical abuse as children may be at increased risk for diabetes and heart disease, a new study suggests.

Researchers examined nearly 350 black and white women in the Pittsburgh area who were between 42 to 52 years old at the start of the study. About 34 percent of the women said they had been victims of some form of childhood abuse.

Compared to other women in the study, which was published online in the journal Health Psychology, those with a history of childhood physical abuse were about twice as likely to have high blood pressure, high blood sugar, a larger waistline and poor cholesterol levels.

Collectively, these health issues are known as metabolic syndrome. Previous research suggests that people with metabolic syndrome are at increased risk for heart disease and type 2 diabetes.

The link between childhood physical abuse and metabolic syndrome was separate from traditional risk factors for the syndrome, such as smoking, lack of physical activity, menopause, alcohol use and depression. This persistent association suggests that abuse plays a unique role in women's cardiovascular health, the researchers said.

"Our research shows us that childhood abuse can have long-lasting consequences -- even decades later -- on women's health, and is related to more health problems down the road," study co-author Aimee Midei, a graduate student in psychology at the University of Pittsburgh, said in a journal news release.

"It's possible that women with histories of physical abuse engage in unhealthy eating behaviors or have poor stress regulation," Midei said. "It appears that psychology plays a role in physical health even when we're talking about traumatic incidents that happened when these women were children."

Although the study found an association between childhood physical abuse and an increased occurrence of metabolic syndrome later in life, it did not prove a cause-and-effect relationship. The study also found no association between childhood sexual and emotional abuse and metabolic syndrome.

More information

The American Academy of Family Physicians has more about metabolic syndrome.

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Abuse during childhood may contribute to obesity in adulthood

ScienceDaily (July 2, 2012) — Investigators from Boston University School of Medicine (BUSM) and Boston University's Slone Epidemiology Center report research findings that may shed light on influences on obesity during adulthood. Appearing in the journal Pediatrics, the study found an association of severity of sexual and physical abuse during childhood and adolescence with obesity during adulthood.

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The findings were based on the ongoing Black Women's Health Study, which has followed a large cohort of African-American women since 1995. Information provided in 2005 by more than 33,000 participants on early life experiences of abuse was assessed in relation to two measures of obesity: body mass index of 30 kg/m2 or more as a measure of overall obesity and waist circumference greater than 35 inches as a measure of central obesity.

The risk of obesity in 2005 by either measure was estimated to be approximately 30 percent greater among women in the highest category of physical and sexual abuse than in women who reported no abuse. The association was dampened but not fully explained by allowance for reproductive history, diet, physical activity and depressive symptoms, which might have been intermediates between abuse and weight gain.

According to the researchers, the findings add to growing evidence that experiences during childhood may have long-term health consequences. "Abuse during childhood may adversely shape health behaviors and coping strategies, which could lead to greater weight gain in later life," explained Renee Boynton-Jarrett, MD, the lead investigator of the study and a pediatric primary care physician at Boston Medical Center. She also noted that metabolic and hormonal disruptions resulting from abuse could have that effect and that childhood abuse could be a marker for other adversities. "Ultimately, greater understanding of pathways between early life abuse and adult weight status may inform obesity prevention and treatment approaches." Boynton-Jarrett cautioned that further studies are needed to clarify just which factors are responsible for the association of abuse with obesity and noted there is a consensus that pediatric providers should screen for abuse.

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Phthalate, environmental chemical is linked to higher rates of childhood obesity

ScienceDaily (June 26, 2012) — Obese children show greater exposure than nonobese children to a phthalate, a chemical used to soften plastics in some children's toys and many household products, according to a new study, which found that the obesity risk increases according to the level of the chemical found in the bloodstream.

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The study will be presented Saturday at The Endocrine Society's 94th Annual Meeting in Houston.

The chemical, di-ethylhexyl phthalate (DEHP), is a common type of phthalate, a group of industrial chemicals that are suspected endocrine disruptors, or hormone-altering agents.

In the study, children with the highest DEHP levels had nearly five times the odds of being obese compared with children who had the lowest DEHP levels, study co-author Mi Jung Park, MD, PhD, said.

"Although this study cannot prove causality between childhood obesity and phthalate exposure, it alerts the public to recognize the possible harm and make efforts to reduce this exposure, especially in children," said Park, a pediatric endocrinologist in Seoul, Korea, at Sanggye Paik Hospital and professor at Inje University College of Medicine.

Phthalates are found in some pacifiers, plastic food packages, medical equipment and building materials such as vinyl flooring, and even in nonplastic personal care products, including soap, shampoo and nail polish.

Prior research has shown that phthalates may change gene expression associated with fat metabolism, according to Dr. Park. Because past research suggested a link between concentrations of phthalate metabolites and increased waist size in adults, her group studied a possible connection with childhood obesity.

Dr.Park and colleagues measured serum levels of DEHP in 204 children: 105 obese and 99 healthy-weight youth ages 6 to 13 years. The researchers divided these DEHP measurements into four groups from the lowest detectable level (40.2 nanograms per milliliter, or ng/mL) to the highest (69.7 to 177.1 ng/mL).

They found that the obese children had a significantly higher average DEHP level than did the nonobese controls (107 versus 53.8 ng/mL, respectively). In particular, a high DEHP level correlated with body mass index and percentage of fat mass. This increased risk of obesity with elevation of DEHP levels was independent of factors such as physical activity and daily calorie intake, according to the authors.

"More research in people is needed to determine whether DEHP exposure contributes to childhood obesity," Dr.Park said.

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Childhood obesity linked to math performance, researcher says

ScienceDaily (June 14, 2012) — Childhood obesity has increased dramatically throughout the past 40 years and has been tied to many health problems. Now, a University of Missouri researcher has found that children's weight is associated with their math performance.

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"The findings illustrate the complex relationships among children's weight, social and emotional well-being, academics and time," said Sara Gable, associate professor in the MU Department of Nutrition and Exercise Physiology, who led the study.

Gable looked at more than 6,250 children from the Early Childhood Longitudinal Study-Kindergarten Cohort, a nationally representative sample. The children were followed from the time they started kindergarten through fifth grade. At five points in time, parents provided information about their families, teachers reported on the children's interpersonal skills and emotional well-being, and children were weighed and measured; they also took academic tests.

When compared with children who were never obese, boys and girls whose obesity persisted from the start of kindergarten through fifth grade performed worse on the math tests, starting in first grade. Their lower performance continued through fifth grade. For boys whose obesity emerged later -- in third or fifth grade -- no such differences were found. For girls who became obese later, poorer math performance was temporary.

In addition, for girls who were persistently obese, having fewer social skills explained some part of their poorer math performance. For both boys and girls who were persistently obese, feeling sadder, lonelier and more anxious also explained some of their poorer math performance.

"Our study suggests that childhood obesity, especially obesity that persists throughout the elementary grades, can harm children's social and emotional well-being and academic performance," Gable said.

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Soft drink consumption not the major contributor to childhood obesity, study says

ScienceDaily (June 14, 2012) — Most children and youth who consume soft drinks and other sweetened beverages, such as fruit punch and lemonade, are not at any higher risk for obesity than their peers who drink healthy beverages, says a new study published in the October issue of Applied Physiology, Nutrition, and Metabolism. The study examined the relationship between beverage intake patterns of Canadian children and their risk for obesity and found sweetened beverage intake to be a risk factor only in boys aged 6-11.

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"We found sweetened drinks to be dominant beverages during childhood, but saw no consistent association between beverage intake patterns and overweight and obesity," says lead author Susan J. Whiting. "Food and beverage habits are formed early in life and are often maintained into adulthood. Overconsumption of sweetened beverages may put some children at increased risk for overweight and obesity. Indeed, boys aged 6-11 years who consumed mostly soft drinks were shown to be at increased risk for overweight and obesity as compared with those who drank a more moderate beverage pattern."

The authors determined beverage consumption patterns among Canadian children aged 2-18 years using cluster analysis where sociodemographics, ethnicity, household income, and food security were significantly different across the clusters. Data were divided into different age and gender groups and beverage preferences were studied. For this study the sweetened, low-nutrient beverages, categorized according to Canada's Food Guide, consisted of fruit-flavoured beverages, beverages with less than 100% fruit juice, lemonades, regular soft drinks, and sweetened coffees or teas.

The authors found the main predictors of childhood obesity in Canadian children were household income, ethnicity, and household food security.

The study "Beverage patterns among Canadian children and relationship to overweight and obesity" appears in the October issue of Applied Physiology, Nutrition, and Metabolism.

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CT scans in childhood increase cancer risk: study

"A youth undergoes a CT Scan at a hospital. Children exposed to multiple CT scans could be up to three times likelier to contract cancer of the blood, brain or bone marrow later in life, according to research published Thursday. (AFP Photo/)" title

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Caesarean section delivery may double risk of childhood obesity: May be due to different gut bacteria

ScienceDaily (May 23, 2012) — Caesarean section delivery may double the risk of subsequent childhood obesity, finds research published online in the Archives of Disease in Childhood.

See Also:Health & MedicinePregnancy and ChildbirthObesityGynecologyDiet and Weight LossInfant's HealthChildren's HealthReferenceBreech birthBirth weightBody mass indexNutrition and pregnancy

Caesarean section delivery has already been linked to an increased risk of subsequent childhood asthma and allergic rhinitis, and around one in three babies born in the US is delivered this way.

The authors base their findings on 1255 mother and child pairs, who attended eight outpatient maternity services in eastern Massachusetts, USA between 1999 and 2002.

The mums joined the study before 22 weeks of pregnancy, and their babies were measured and weighed at birth, at six months, and then at the age of three, when the child's skinfold thickness, a measure of body fat, was also assessed.

Out of the 1255 deliveries, around one in four (22.6%; 284) were by caesarean section, and the remainder (77.4%; 971) were vaginal deliveries.

Mums who delivered by c-section tended to weigh more than those delivering vaginally, and the birthweight for gestational age of their babies also tended to be higher. These mums also breastfed their babies for a shorter period.

But irrespective of birth weight, and after taking account of maternal weight (BMI) and several other influential factors, a caesarean section delivery was associated with a doubling in the odds of obesity by the time the child was 3 years old.

Just under 16% of children delivered via c-section were obese by the age of 3 compared with 7.5% of those born vaginally.

Children delivered by c-section also had higher BMI and skinfold thickness measurements by the age of 3.

The researchers speculate that one possible explanation for their findings is the difference in the composition of gut bacteria acquired at birth between the two delivery methods.

They highlight previous research showing that children born by c-section have higher numbers of Firmicutes bacteria and lower numbers of Bacteroides bacteria in their guts. These two groups make up the bulk of gut flora.

Other research has also suggested that obese people have higher levels of Firmicutes bacteria.

It may be that gut bacteria influence the development of obesity by increasing energy extracted from the diet, and by stimulating cells to boost insulin resistance, inflammation, and fat deposits, say the authors.

"An association between caesarean birth and increased risk of childhood obesity would provide an important rationale to avoid non-medically indicated caesarean section," write the authors.

Mums who choose this delivery option should be made aware of the potential health risks to her baby, including the possibility of obesity, they say.

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Experimental Drug Helps Fight Some Childhood Cancers, Study Finds

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Treating childhood obesity: A family affair

ScienceDaily (May 1, 2012) — With nearly one-third of American children being overweight or obese, doctors agree that there is an acute need for more effective treatments. In many weight management programs, the dropout rate can be as high as 73 percent, and even in successful programs, the benefits are usually short term.

See Also:Health & MedicineStaying HealthyObesityChildren's HealthDiet and Weight LossWorkplace HealthFitnessLiving WellReferencePediatricsOverweightDiabetes mellitus type 2Body mass index

Although family-based approaches to pediatric obesity are considered the gold standard of treatment, theories of the family and how it functions have not been incorporated into effective interventions, according to a study published in the May issue of the International Journal of Obesity by researchers at Wake Forest Baptist Medical Center.

"The field of family studies provides an innovative approach to the difficult problem of pediatric obesity, building on the long-established approach of family-based treatment," said Joseph Skelton, M.D., assistant professor of pediatrics and director of the Brenner FIT (Families in Training) Program at Wake Forest Baptist, and lead author of the study. Skelton and his research team reviewed medical literature published between 1990 and 2011 to identify the use of prominent family theories in pediatric obesity research. Of the 76 manuscripts found, 13 were selected for the study.

Wake Forest Baptist researchers found limited use of family theories in the study of pediatric obesity, particularly in weight management treatments. Family behavioral theories can provide valuable insight into the complexities of families, and increased use of these theories in both research and practice may help in the development of more effective treatments for childhood obesity, the study found.

"Traditionally doctors looked at the patient as the one in the family to focus on, but now we have to look at the entire family as the patient," Skelton said.

"One of the problems we found was that there wasn't even a clear definition of family in the literature. A two-parent household with a stay-at-home mother and working father is no longer the norm. Inability to define the family makes it difficult to apply a straightforward model of family function to child health and weight management."

In the clinic setting, families are often represented by a child and a parent, typically the mother. However, this often does not accurately reflect family complexity and it doesn't define which family members should be included in treatment, Skelton said. A common theme in the field of family studies is that families are a system, made up of interdependent units. Intervening with one unit, such as a mother and a child, will influence other units. These interpersonal relationships influence the health behaviors of the child and the family as a whole, according to the study.

"The challenge is to find ways to incorporate the entire family in the process, while allowing for different schedules and different age kids with different health needs," Skelton said. "If we don't find more effective treatments and this epidemic continues, these children will likely go on to become obese adults, resulting in an entire generation with lower life expectancies than their parents' generation."

Skelton and his team at Brenner FIT have begun incorporating theories of the family into their research and in their treatment approach, and are finding ways to engage more members of the family in treatment.

Funding for the study was provided by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, the Duke Endowment and the Kate B. Reynolds Charitable Foundation.

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Childhood Obesity May Raise Odds of Adult Liver Cancer

HealthDay – 13 mins ago FRIDAY, April 20 (HealthDay News) -- Adults who were obese as children are at increased risk for liver cancer, a new study suggests.

Researchers looked at the birth weight and body-mass index (a measurement of body fat based on height and weight commonly called BMI) of more than 165,000 men and 160,000 women in Denmark born between 1930 and 1989.

Of those participants, 252 developed hepatocellular carcinoma, the most common form of liver cancer in adulthood.

The study authors calculated that at age 7, the risk of developing hepatocellular carcinoma increased by 12 percent for every one-point increase in BMI. By age 13, that risk increased to 25 percent. Therefore, as units of BMI increased into adulthood, so did the risk of developing hepatocellular carcinoma. This was consistently similar across both genders and all ages.

Other factors associated with liver cancer include alcoholism, infection by hepatitis B and C, and other liver diseases. But the study results did not change when participants with these factors were removed from the study, which indicates that childhood obesity was the major factor in the development of hepatocellular carcinoma, the researchers said.

The study was slated for presentation Thursday at the International Liver Congress in Barcelona.

"Childhood obesity not only leads to the development of many adverse metabolic conditions -- such as type 2 diabetes and heart disease -- but also fatty liver disease, which may subsequently result in liver cancer," Dr. Frank Lammert, a scientific committee member of the European Association for the Study of the Liver, said in an association news release.

"The importance of maintaining a healthy childhood BMI cannot be underestimated," Lammert said in the release. "These alarming study results point to a potential correlation between childhood obesity and development of liver cancer in adulthood."

Data and conclusions presented at meetings should be considered preliminary until published in a peer-reviewed medical journal.

More information

The American Liver Foundation has more about liver cancer.

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Scientists Pinpoint Childhood Obesity Genes

HealthDay – 43 mins ago SUNDAY, April 8 (HealthDay News) -- For the first time, scientists have isolated mutations at two gene locations that seem to predispose children to becoming obese.

"We see a clear genetic signature to childhood obesity, showing that there is more than just an environmental component to this disease," Struan Grant, senior author of the research, said at an April 5 press conference.

Although known genes have been linked to adult obesity and also to extreme forms of childhood obesity, the newly identified genes confer only a modest risk of developing common childhood obesity. But they are "very common in the population," Grant added in a telephone interview.

Grant is associate director of the Center for Applied Genomics at the Children's Hospital of Philadelphia Research Institute. His research was published online April 8 in Nature Genetics.

Obesity has become a public health crisis of global proportions, affecting not only adults but also, increasingly, children.

"In the U.S., the prevalence of childhood obesity has tripled in recent decades and related health care costs have quadrupled," said Dr. Karen Winer, a program officer in the endocrinology, nutrition and growth branch of the Eunice Kennedy Shriver U.S. National Institute of Child Health and Human Development, which funded the study.

Clear environmental factors such as changing nutrition and reduced physical exercise have played a role in the childhood obesity crisis, but no genes had, until now, been identified.

The authors of this study pooled results from 14 genome-wide association studies conducted in the United States, Canada, Australia and Europe, involving a total of 5,530 children who were obese and 8,318 non-obese kids ("controls"), all of European descent.

This is the largest collection of DNA related to childhood obesity in the world, Winer said.

Obesity was defined as being above the 95th percentile in body mass index (a measurement that takes into account height and weight) while the healthy controls were all in the leaner half of the population.

When data was combined, two genes stood out: OLFM4 and HOXB5. The genes also showed signals in groups of extremely obese children.

And the genes were identifiable but weaker in adults, indicating that "these variants are conferring their risk early on in life and are really impactful in the first years of life," Grant said at the press conference.

Scientific literature to date indicates that the genes may be operating in the gut.

"We would look probably in that tissue area to see how it was conferring risk," Grant said at the press conference.

It's possible, for instance, that the genes may interact with food, he said.

Eric Schadt, chairman of the department of genetics and genomic sciences at Mount Sinai School of Medicine in New York City, said: "Absolutely, this is a disease that has genetic components and very strong environmental components and likely very strong genetic-by-environmental components. It's very, very complicated. We're only scratching the surface of genetic determinations of childhood obesity."

Once scientists learn more about the genes and how they work, they may lead to new treatments, added Schadt, who was not involved with the study.

More information

The U.S. Centers for Disease Control and Prevention has more on childhood obesity.

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