Even in young children: Higher weight = higher blood pressure

June 13, 2019

Science Daily/European Society of Cardiology

Overweight four-year-olds have a doubled risk of high blood pressure by age six, raising the hazard of future heart attack and stroke. That's the finding of a study published today in the European Journal of Preventive Cardiology, a journal of the European Society of Cardiology (ESC).

"The myth that excess weight in children has no consequences hampers the prevention and control of this health problem," said study author Dr Iñaki Galán, of Carlos III Health Institute, Madrid, Spain. "Parents need to be more physically active with young children and provide a healthy diet. Women should shed extra pounds before becoming pregnant, avoid gaining excess weight during pregnancy, and quit smoking, as these are all established risk factors for childhood obesity."

According to the World Health Organization, childhood obesity is one of the most serious public health challenges of the 21st century. The problem is global and the prevalence has increased at an alarming rate. In 2016, more than 41 million children under the age of five were overweight.

This study, based on the ELOIN cohort, examined the link between excess weight and high blood pressure in 1,796 four-year-olds who were followed up two years later. Blood pressure was measured at both time points, as was body mass index (BMI in kg/m2) and waist circumference.

Compared to children maintaining a healthy weight between ages four and six, those with new or persistent excess weight according to BMI had 2.49 and 2.54 higher risks of high blood pressure, respectively. In those with new or persistent abdominal obesity, the risks for high blood pressure were 2.81 and 3.42 greater, respectively. Children who lost weight did not have an increased risk of high blood pressure. The findings applied to all children regardless of sex or socioeconomic status.

"There is a chain of risk, whereby overweight and obesity lead to high blood pressure, which heightens the chance of cardiovascular disease if allowed to track into adulthood," said Dr Galán. "But the results show that children who return to a normal weight also regain a healthy blood pressure."

The best way to maintain a healthy weight and lose excess kilos is to exercise and eat a healthy diet, said Dr Galán. In addition to the central role of parents, the school curriculum needs to include three to four hours of physical activity every week. Teachers should supervise activities during breaks, while schools can offer games and sports after classes and provide nutritionally balanced meals and snacks.

Doctors should routinely assess BMI and waist circumference at early ages, added Dr Galán. "Some paediatricians think the harms of overweight and obesity begin in adolescence but our study shows they are mistaken," he said. "We need to detect excess weight as soon as possible so the damaging impact on blood pressure can be reversed."

Overweight children should have their blood pressure measured. Three consecutive elevated readings constitute high blood pressure. In young children, the most common cause is excess weight, but doctors will rule out other reasons such as heart defects, kidney disease, genetic conditions, and hormonal disorders. If the cause is overweight, more activity and dietary improvements will be advised. If lifestyle changes don't help, blood pressure lowering medication may be prescribed.

Dr Galán noted that overweight in children is most accurately assessed using both BMI and waist circumference. In the study, using either measurement alone would have missed 15% to 20% of cases.

https://www.sciencedaily.com/releases/2019/06/190613095224.htm

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

Gut microbiota of infants predicts obesity in children

October 23, 2018

Science Daily/American Society for Microbiology

Evaluating the gut microbiota of infants may help identify children who are at risk for becoming overweight or obese. The research revealed that gut microbiota composition at two years of life is associated with body mass index (BMI) at age 12. In addition, the BMI at age two was not significantly higher in children who later became overweight/obese, indicating that gut microbiota composition may be the earliest warning sign for detecting obesity.

"Our study provides more evidence that the gut microbiota might be playing a role in later obesity," said lead author Maggie Stanislawski, PhD, who is a research associate at the LEAD Center, University of Colorado Anschutz Medical Campus, Colorado School of Public Health, Aurora, Colorado. "If our findings can be confirmed by other studies, the gut microbiota might play an important part of the obesity prediction algorithm, to identify at-risk kids early in life, before they start to gain any excess weight that might put them at risk for later obesity."

Prior to this study, a growing body of evidence has demonstrated that the gut microbiota plays a role in obesity, and there is some evidence that the role might be causal. To shed more light on the issue, the University of Colorado researchers collaborated with Merete Eggesbø, MD, PhD, who leads the NoMIC study at the Norwegian Institute of Public Health in Oslo, and analyzed data from 165 infants who had BMI measured at 12 years.

The NoMIC study began in 2002 as one of the earliest birth cohorts in the world to investigate the early life gut microbiome and includes roughly 550 kids who are now teenagers. The study recruited moms and infants in the hospital at the time of delivery. At 12 years of age, 20% of the 165 children in the study cohort were overweight or obese.

The researchers compared the BMI at age 12 with gut microbiota samples from six time points throughout their childhood, at day 4, day 10, one month, four months, one year, and two years. They performed 16s rRNA gene sequencing on the gut microbiota samples. "We looked at whether there were specific taxa that were predictive of later BMI at each time point," said Dr. Stanislawski.

The researchers found qualitative differences in the composition of children's gut microbiota at day ten and at two years that were associated with BMI z-scores at age 12. BMI z-scores are measures of relative weight adjusted for child age and sex. They also examined how much of the variation in childhood BMI z-scores was explained by the early gut microbiota taxa.

"At the early time points, there was somewhat of a relationship between the gut microbiota taxa and later BMI, but the relationship was much stronger as the kids got older," said Dr. Stanislawski. "At one year, it was stronger than the earlier time points. At two years, it was the strongest. We found this very interesting because, at two years, there wasn't any obvious phenotype in terms of whether or not the kids were going to become obese. Kids who became obese later in life didn't have high BMI z-scores at age 2. The findings suggest that the gut microbiota phenotype was present before any overt sign of overweight or obesity. Since the gut microbiota is influenced by diet, this association could also reflect dietary choices that are precursors to obesity."

Dr. Stanislawski said the study was limited in that the entire cohort was of Norwegian descent. This research, she said, needs to be repeated in other cohorts, but if replicated, it may lead to a new tool to identify kids at risk for developing obesity. "It is better to identify at-risk kids early. It is easier to prevent obesity than to reverse it," said Dr. Stanislawski. "It's possible that if we follow up some of these findings in the lab, it will reveal more about the pathophysiology of obesity as well."

The study also exposed a potential health caution. The researchers found that some gut microbes that are generally thought to be healthy in both children and adults were associated with higher childhood BMI. This highlights that we do not fully understand the dynamics of the gut colonization process.

"When I was pregnant, my doctor suggested giving the baby probiotics every day, and I think a lot of people are giving their infants probiotics," said Dr. Stanislawski. "However, it might not be the best idea to give babies the same types of bacteria every day, particularly in very early life when overloading the gut with one or two strains may prevent colonization with other types of important bacteria." She pointed out that one way to improve the gut microbiota in kids and adults is to eat a well-balanced diet with lots of different types of vegetables and fiber, so there are lots of things feeding the gut microbiota.

Future research will focus on further examining the colonization process in relation to other markers of metabolic health in children. "We will focus on the temporal dynamics of first two years," said Dr. Stanislawski.

https://www.sciencedaily.com/releases/2018/10/181023085640.htm