Breaking Childhood Obesity
When it comes to the rising rate of childhood obesity, there are several factors and reasons why the problem exists. One Auburn University College of Human Sciences researcher is taking a closer look at why the problem tends to be more prominent in certain racial and ethnic groups and what solutions could help combat this growing problem.
Dr. Geetha Thangiah, an associate professor in the College of Human Sciences’ Nutritional Sciences Department, is focusing on molecular mechanisms that influence the development of obesity, diabetes and metabolic syndrome in minority racial/ethnic populations. More specifically, Thangiah’s research is focused on obesity in elementary school children 6-10 years old.
According to the Centers for Disease Control and Prevention, the rate of childhood obesity in the United States was 20.7% in ages 6-11 in 2017-2020. Furthermore, childhood obesity prevalence was even greater among Hispanic children at 26.2% and in non-Hispanic Black children at 24.8% in the same period. However, in comparison, the rate of obesity in non-Hispanic white children was 16.6%. Recently, the Alabama Department of Health reported that one in five children is obese, the fifth highest in the country. These numbers continue to steadily increase.
“I was hired here as a health disparity cluster faculty [member], and this position provides me the opportunity to explore disparities research,” Thangiah said. “As you see, the prevalence of childhood obesity is higher in Hispanic and non-Hispanic Black children and is dependent on the socioeconomic status of the household. It is found to be greater in families where parents have a low level of education or low income.”
In the College of Human Sciences, the mission statement of “improving quality of life and changing the world” is being lived out every day in Thangiah’s research as she takes a closer look at childhood obesity rates.
“Childhood obesity is a complex disease, and there are multiple factors that influence body weight gain,” Thangiah said. “Daily lifestyle habits like eating patterns, physical activity, parental perceptions, environment and genetic factors all play a major role.”
The answer to fixing the childhood obesity problem is much more complex than just cutting caloric intake. Thangiah’s research studies have shown that DNA methylation of specific genes is associated with obesity, but significant gaps in this research include an understanding of how the racial and ethnic differences in epigenome-wide methylation affect obesity among children.
“The genetic factors are directly inherited from your biological parents, so that’s how genes form. Epigenetics is the study of how lifestyle habits such as diet, sleep timing, physical activity and environment can cause changes in how the genes work,” Thangiah said. “The underlying DNA sequence we inherit from our parents does not change, but all these factors affect the way genes work.”
The good news is that epigenetic changes that occur are reversible. So, lifestyle changes like improved eating patterns, physical activity and sleep timing will have a positive effect on reversing childhood obesity.
“What we have found so far with daily lifestyle habits is that children who go to bed later than 8:45 p.m., who eat dinner after 7 p.m., and who watch more than one hour of television per day tend to be more obese,” Thangiah said. “Some parents pressure their children to eat and not be wasteful even if the child is full, and those children tend to be more obese.”
In addition to studying lifestyle factors, Thangiah and her team also collaborated with the Mayo Clinic in Rochester, Minnesota, to study the differences in the various microbes that live in the stomachs of African American/Black children and European/white children.
“We looked at the gut microbiome that is present in the fecal samples of children,” Thangiah said. “We found significant diversity in the microbiome profile between African American and white children. The gut microbiome is made up of bacteria, fungi and other healthy and unhealthy microbes present in the stomach. Microbial imbalances cause problems like obesity, diabetes, high cholesterol and more. Microbes play an important role in digestion and our immune system. We can improve healthy microbes by eating a variety of fruits, vegetables, whole grains and fermented foods.”
Thangiah’s aim is to understand and address the gap in the disparities in childhood obesity. The findings will be critical to developing effective clinical interventions to reduce childhood obesity.
“Research from our lab will examine the relation of race/ethnicity and obesity with epigenome-wide DNA methylation profile among children 6-10 years old,” Thangiah said. “Research is an ongoing process and we have already collected saliva samples, so we are going to look at the methylation profile and its association with lifestyle habits, such as diet. However, there are multiple factors for the disparities in childhood obesity and it’s not just one reason. If that were the case, then it would be easy to figure out, so there is no deadline for this research.”
For more information on the College of Human Sciences’ Department of Nutritional Sciences, visit humsci.auburn.edu/nutrition.