Being teased about weight linked to more weight gain among children
May 30, 2019
Science Daily/NIH/Eunice Kennedy Shriver National Institute of Child Health and Human Development
Youth who said they were teased or ridiculed about their weight increased their body mass by 33 percent more each year, compared to a similar group who had not been teased, according to researchers at the National Institutes of Health. The findings appear to contradict the belief that such teasing might motivate youth to change their behavior and attempt to lose weight. The study was conducted by Natasha A. Schvey, Ph.D., of the Uniformed Services University of the Health Sciences in Bethesda, MD, and colleagues at NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development and National Institute of Diabetes and Digestive and Kidney Diseases. It appears in Pediatric Obesity.
The study involved 110 youth who were an average of 11.8 years of age when they enrolled. The participants were either overweight (defined as a body mass index above the 85th percentile) when they began the study or had two parents who were overweight or obese. At enrollment, they completed a six-item questionnaire on whether they had been teased about their weight. They then participated in annual followup visits for the next 15 years.
The researchers found that youth experiencing high levels of teasing gained an average of .20 kg (.44 lbs) per year more than those who did not. The authors theorize that weight-associated stigma may have made youths more likely to engage in unhealthy behaviors, such as binge eating and avoiding exercise. Another possible explanation is that the stress of being teased could stimulate the release of the hormone cortisol, which may lead to weight gain.
https://www.sciencedaily.com/releases/2019/05/190530101213.htm
Young children's oral bacteria may predict obesity
September 19, 2018
Science Daily/Penn State
Weight gain during early childhood is related to the composition of oral bacteria of two-year-old children, suggesting this understudied aspect of a children's collection of microorganisms could serve as an early indicator for childhood obesity.
Weight gain trajectories in early childhood are related to the composition of oral bacteria of two-year-old children, suggesting that this understudied aspect of a child's microbiota -- the collection of microorganisms, including beneficial bacteria, residing in the mouth -- could serve as an early indicator for childhood obesity. A study describing the results appears September 19 in the journal Scientific Reports.
"One in three children in the United States is overweight or obese," said Kateryna Makova, Pentz Professor of Biology and senior author of the paper. "If we can find early indicators of obesity in young children, we can help parents and physicians take preventive measures."
The study is part of a larger project with researchers and clinicians at the Penn State Milton S. Hershey Medical Center called INSIGHT, led by Ian Paul, professor of pediatrics at the Medical Center, and Leann Birch, professor of foods and nutrition at the University of Georgia. The INSIGHT trial includes nearly 300 children and tests whether a responsive parenting intervention during a child's early life can prevent the development of obesity. It is also designed to identify biological and social risk factors for obesity.
"In this study, we show that a child's oral microbiota at two years of age is related to their weight gain over their first two years after birth," said Makova.
The human digestive tract is filled with a diverse array of microorganisms, including beneficial bacteria, that help ensure proper digestion and support the immune system. This "microbiota" shifts as a person's diet changes and can vary greatly among individuals. Variation in gut microbiota has been linked to obesity in some adults and adolescents, but the potential relationship between oral microbiota and weight gain in children had not been explored prior to this study.
"The oral microbiota is usually studied in relation to periodontal disease, and periodontal disease has in some cases been linked to obesity," said Sarah Craig, a postdoctoral scholar in biology at Penn State and first author of the paper. "Here, we explored any potential direct associations between the oral microbiota and child weight gain. Rather than simply noting whether a child was overweight at the age of two, we used growth curves from their first two years after birth, which provides a more complete picture of how the child is growing. This approach is highly innovative for a study of this kind, and gives greater statistical power to detect relationships."
Among 226 children from central Pennsylvania, the oral microbiota of those with rapid infant weight gain -- a strong risk factor for childhood obesity -- was less diverse, meaning it contained fewer groups of bacteria. These children also had a higher ratio of Firmicutes to Bacteroidetes, two of the most common bacteria groups found in the human microbiota.
"A healthy person usually has a lot of different bacteria within their gut microbiota," said Craig. "This high diversity helps protect against inflammation or harmful bacteria and is important for the stability of digestion in the face of changes to diet or environment. There's also a certain balance of these two common bacteria groups, Firmicutes and Bacteroidetes, that tends to work best under normal healthy conditions, and disruptions to that balance could lead to dysregulation in digestion."
Lower diversity and higher Firmicutes to Bacteroidetes (F:B) ratio in gut microbiota are sometimes observed as a characteristic of adults and adolescents with obesity. However, the researchers did not see a relationship of weight gain with either of these measures in gut microbiota of two-year-olds, suggesting that the gut microbiota may not be completely established at two years of age and may still be undergoing many changes.
"There are usually dramatic changes to an individual's microbiota as they develop during early childhood," said Makova. "Our results suggest that signatures of obesity may be established earlier in oral microbiota than in gut microbiota. If we can confirm this in other groups of children outside of Pennsylvania, we may be able to develop a test of oral microbiota that could be used in clinical care to identify children who are at risk for developing obesity. This is particularly exciting because oral samples are easier to obtain than those from the gut, which require fecal samples."
Interestingly, weight gain in children was also related to diversity of their mother's oral microbiota. This could reflect a genetic predisposition of the mother and child to having a similar microbiota, or the mother and child having a similar diet and environment.
"It could be a simple explanation like a shared diet or genetics, but it might also be related to obesity," said Makova. "We don't know for sure yet, but if there is an oral microbiome signature linked to the dynamics of weight gain in early childhood, there is a particular urgency to understand it. Now we are using additional techniques to look at specific species of bacteria -- rather than larger taxonomic groups of bacteria -- in both the mothers and children to see whether specific bacteria species influence weight gain and the risk of obesity."
https://www.sciencedaily.com/releases/2018/09/180919083508.htm
Mothers' sleep, late in pregnancy, affects offspring's weight gain as adults
May 16, 2014
Science Daily/University of Chicago Medical Center
Poor-quality sleep during the third trimester of pregnancy can increase the odds of weight gain and metabolic abnormalities in offspring once they reach adulthood. The effects, caused by epigenetic modifications, impose lasting consequences on the next generation.
The researchers linked the excess weight and changes in metabolism to epigenetic modifications that reduce expression of the gene for adiponectin -- a hormone that helps regulate several metabolic processes, including glucose regulation. Lower levels of adiponectin correlate with increased body fat and reduced activity.
"Disrupted sleep is a common problem during the final trimester of a pregnancy," said study director, sleep specialist David Gozal, MD, the Herbert T Abelson professor of pediatrics at the University of Chicago. "For some women, sleep fragmentation, especially sleep apnea, can be profound. We wanted to devise a system that enabled us to measure the potential impact of fragmented sleep on the fetus, which is uniquely susceptible so early in life."
Adiponectin is usually a "beneficial hormone," Gozal said. "It can reduce cholesterol, make you more sensitive to insulin, protect your heart." As adiponectin levels in adults go up, body-fat percentage tends to go down. Expression of the adiponectin gene was reduced in the offspring of sleep-fragmented mothers, especially in their visceral fat cells.
A closer look revealed epigenetic changes, such as methylation and histone modification, which shut down selected genes, often in response to environmental stresses.
"We found that the offspring of sleep-deprived mothers had largely inactivated AdipoQ, the adiponectin gene," Gozal said. "Such changes may affect other genes as well; we haven't studied all the potential targets yet. Even so, this is the first example of a perturbation during pregnancy that translates into a genetic risk, in midlife, for the next generation."
"This is kind of scary," he added. "Will this generation, the sons of sleep-deprived mice, who are already at increased risk for metabolic syndrome and type 2 diabetes, transmit this inherited risk, perhaps compounded by new stresses, to their offspring?"
http://www.sciencedaily.com/releases/2014/05/140516092305.htm
Light exposure linked to weight gain in children
October 23, 2015
Science Daily/Queensland University of Technology
A world-first study has revealed pre-schoolers exposed to more light earlier in day tend to weigh more. She says the research suggests light exposure, artificial and natural, needs to be part of the conversation about the weight of children, along with calorie intake, decreased physical activity and sleep patterns.
http://images.sciencedaily.com/2015/10/151023105914_1_540x360.jpg
Ms Pattinson said it is known the timing, intensity and duration of exposure to both artificial and natural light have acute biological effects in mammals. (Stock image of normal healthy child)
Credit: © Sabphoto / Fotolia
Cassandra Pattinson, a PhD student and her colleagues studied 48 children aged three to five from six Brisbane childcare centres over a two week period, measuring each child's sleep, activity and light exposure along with their height and weight to calculate their BMI.
"We found moderate intensity light exposure earlier in the day was associated with increased body mass index (BMI) while children who received their biggest dose of light -- outdoors and indoors -- in the afternoon were slimmer," said Ms Pattinson who will present her findings at the ASA Sleep Downunder Conference in Melbourne on 23 October.
"Surprisingly physical activity was not associated with the body mass of the children but sleep timing and light exposure was. This is the first time light has been shown to contribute to weight in children.
"With an estimated 42 million children around the globe under the age of five being classified as overweight or obese, it is a significant breakthrough and a world-first.
"Thanks to artificial lighting, including light given off by tablets, mobile phones, night lights, and television, modern children are exposed to more environmental light than any previous generation. This increase in light exposure has paralleled global increases in obesity."
The research team, from QUT's Institute of Health and Biomedical Innovation, worked with the Centre for Children's Health Research
Ms Pattinson said it is known the timing, intensity and duration of exposure to both artificial and natural light have acute biological effects in mammals.
"The circadian clock -- also known as the internal body clock -- is largely driven by our exposure to light and the timing of when that happens. It impacts on sleep patterns, weight gain or loss, hormonal changes and our mood," Ms Pattinson said
"Recent research in adults suggests exposure to light later in the day is associated with increased body mass, but no studies had investigated these effects in young children and it turns out it has the opposite effect.
"While adults who take in more morning light are slimmer, pre-school children exposed to morning light tend to be heavier.
"Factors that impact on obesity include calorie intake, decreased physical activity, short sleep duration, and variable sleep timing. Now light can be added to the mix."
Ms Pattinson said the next step was to figure out how the research can be used in the fight against obesity in children.
"We plan to conduct further studies with pre-schoolers and also infants," she said.
"Animal studies have shown that timing and intensity of light exposure is critical for metabolic functioning and weight status. Our findings suggest that the same applies to us.
"This research suggests that exposure to different types of light at different times now needs to be part of the conversation about the weight of children."