This article is the first in a series at metabolism.com; “Overweight Kids….Trouble in Paradise”.
In the opener, we touch on many aspects of what can be a toxic tangle. In coming articles we plan to break out and do a deeper dive into each of the aspects presented. Subscribe to metabolism.com below to avoid missing the next article, “ Are Overweight Kids Destined for Diabetes?”
By Gary M Pepper, M.D.
Childhood obesity presents one of the most urgent public health issues in the United States today. The intimate interaction between parents and their children further complicates the problem. Parents shape the eating habits their children develop — but that also means parents can serve as important partners helping their children to make healthier nutritional choices.
About one in three children in the United States are classified as overweight or obese, as Kumar and Kelly note in their review published in Mayo Clinic Proceedings in 2017. These authors point out the prevalence of obesity increases as children get older. A 2014 study published in The New England Journal of Medicine, following children from entry into kindergarten through the end of eighth grade, also found that the prevalence of obesity increased by the time kids reached eighth grade. This research showed more children who were overweight when they entered kindergarten became obese by age 14 years old as compared to their normal-weight kindergarten classmates, with the biggest increase in obesity occurring between first and third grades.
Technically speaking, obesity is defined as a body mass index (BMI) of 30 or greater https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmi-m.htm. Childhood obesity comes with other health issues that affect physical and mental health. As the prevalence of childhood obesity has increased, so too has the prevalence of health complications in childhood typically thought to afflict mostly adults. Unfortunately, childhood obesity also tracks into later years: A high percentage of adolescents with obesity continue to remain obese as adults.
The Rise of Childhood Obesity: Complex Causes, Dangerous Combinations
While endocrine and genetic disorders can lead to obesity, most kids don’t have an underlying endocrine or single genetic cause for weight gain. The 2017 review published in Mayo Clinic Proceedings pinpoints a positive energy balance combined with genetic predisposition for weight gain as the most common cause of obesity for children. In other words, kids are taking in more calories through food than they are expending with physical activity.
Childhood obesity results from complex interactions of factors related to a child’s genetics, epigenetics, and environment along with ecological effects such as family, community, and school. The environmental factors that can lead to weight gain are also quite complex and include:
- Adverse life experiences.
- Parental and general culinary culture conditioning.
- Perinatal factors (such as birth size, catch-up growth, antibiotic use).
- Psychosocial and emotional distress.
- Increased caloric consumption, aggravated when specific food intake is resulting in a high sugar burden.
- Decreased caloric expenditure.
The last two factors form a dangerous intersection. Sweet snacks and beverages, fast foods, big portions, and high-glycemic foods all contribute to increased caloric consumption. Decreased caloric expenditure due to reduced physical activity and a trend toward sedentary activities (think: computers, phones, tablets, and televisions) is also on the rise. Together, more calories taken in and less caloric expenditure creates the positive energy balance spurring weight gain.
The current pandemic paints a dire picture. With fewer opportunities for activity and a marked increase in negative emotional triggers, today’s kids are facing a unique challenge. Children need support and guidance to make healthy choices perhaps more than ever before.
Health Issues Associated With Childhood Obesity
Childhood obesity can have serious health implications, with complications manifesting both during adolescence and later in life. Related health issues include:
Children with obesity run an increased risk of developing diabetes. Along with the challenges of managing diabetes itself comes the risk of additional acute and chronic complications.
Abundant research has shown an association between weight in adolescents and the development of diabetes in adulthood. In the past 20 years the incidence of obesity in children and the incidence of diabetes in adulthood has increased hand-in-hand.
A 2017 study by Meyers-Davis et al in The New England Journal of Medicine found the incidence of both type 1 and type 2 diabetes increased significantly among youths between 2002 and 2012. Type 1 diabetes — which usually develops before the age of 35 years and requires insulin treatment — is not necessarily associated with being overweight. Type 2 diabetes, on the other hand, is typically associated with onset after the age of 35 years and almost always has overweight as the major factor.
Despite the common assumption that type 1 diabetes is the “worse” of the two types of diabetes, a study by Constantino et al published in Diabetes Care in 2013 found that early-onset type 2 diabetes came with greater mortality, more complications, and more unfavorable cardiovascular disease risk factors than type 1. Early-onset type 2 diabetes can also create metabolic challenges that last a lifetime.
Weight in childhood can play into cardiovascular health later in life. Twig et al examined the association between body-mass index (BMI) in late adolescence and death from cardiovascular causes as adults, In 2016, their research paper in The New England Journal of Medicine, concludes that overweight and obesity at a young age was strongly associated with increased cardiovascular deaths in adulthood. A 2013 study in Diabetes Care also noted cardiovascular deaths drove the increased death rate associated with type 2 diabetes, with many deaths occurring right in the prime of life.
All in all, childhood obesity can lead to various cardiovascular complications, including:
- Heart disease.
- High blood pressure.
- Sudden death
Diabetes and being overweight have been associated with an increased risk of several cancers, both as individual causes and as intertwined factors. Pearson-Stuttard et al looked at the incidence of cancers (such as liver and endometrial cancers) that could be attributed to diabetes and high BMI in a 2018 study in The Lancet Diabetes & Endocrinology. The study found many cancer cases linked to the prevalence of both. Though the combined effects are striking, the research also indicated that high BMI alone was responsible for twice the number of cancer cases caused by diabetes itself.
Other Health Issues in Childhood and Beyond
Kids (and even parents) might think about many of the above risks as “adult” problems. However, childhood obesity is not just about a risk of death many years in the future. Kids can start experiencing the effects of obesity as young adults — or even earlier.
For example, a study by He et al in Fertility and Sterility published in 2018 investigated the association between childhood obesity and infertility in women. The research noted that childhood obesity appeared to increase the risk of infertility for women of reproductive age.
The 2017 review in Mayo Clinic Proceedings also listed a range of systems in the body that can be impacted by obesity during childhood, including:
As noted in that review, childhood obesity can have psychosocial consequences as well. Children with obesity are more likely than their peers to experience bullying and discrimination, and they may contend with anxiety, depression, and poor self-esteem.
What Can Parents Do Today?
The 2017 review from the Mayo Clinic underscores family-based lifestyle interventions as a cornerstone of weight management for kids. This approach is twofold, incorporating dietary modifications and increased physical activity.
Parents can guide kids learning to make healthier choices for their meals and snacks while encouraging unstructured physical activity (like playing outdoors) for younger kids and more structured physical activity (such as after-school sports) for older kids. At the same time, parents should limit screen time for tasks other than schoolwork — the Mayo Clinic recommends less than two hours of screen time per day for kids older than 2 years old and avoiding screen time altogether for kids younger than 2.
That’s easier said than done, of course. In the current pandemic reality, finding opportunities to turn off the screens and get outside are harder to come by than ever before. Even in the best of times, financial and cultural barriers to healthy eating and physical activity still exist. We’ll explore how parents can empower kids to change their dietary and activity habits later in this series.
Obesity can impact just about every part of the body, and obesity in childhood can have serious implications for years to come. Parents can play a big role in getting their kids motivated to change their eating habits. By offering a compassionate, nonjudgmental source of support, parents can give their kids the tools they need to make healthy and sustainable changes.
Metabolism.com and Dr. Gary Pepper wish to acknowledge and thank Farryl Last for her expert assistance in the preparation of this article,
- Seema Kumar, MD, Aaron S. Kelly, PhD. Review of Childhood Obesity: From Epidemiology, Etiology, and Comorbidities to Clinical Assessment and Treatment. Mayo Clinic Proceedings 2017;92(2):251-265.
- Solveig A. Cunningham, Ph.D., Michael R. Kramer, Ph.D., K.M. Venkat Narayan, M.D. Incidence of Childhood Obesity in the United States. The New England Journal of Medicine 2014;370:403-411.
- Elizabeth J. Mayer-Davis, Ph.D., Jean M. Lawrence, Sc.D., M.P.H., M.S.S.A., Dana Dabelea, M.D., Ph.D., Jasmin Divers, Ph.D., Scott Isom, M.S., Lawrence Dolan, M.D, Giuseppina Imperatore, M.D., Ph.D., Barbara Linder, M.D., Ph.D., Santica Marcovina, Ph.D., Sc.D., David J. Pettitt, M.D., Catherine Pihoker, M.D., Sharon Saydah, Ph.D., M.H.S., Lynne Wagenknecht, Dr.P.H. Incidence Trends of Type 1 and Type 2 Diabetes among Youths, 2002–2012. The New England Journal of Medicine 2017; 376:1419-1429.
- Maria I. Constantino, Lynda Molyneaux, R.N, Franziska Limacher-Gisler, Abdulghani Al-Saeed, M.D., Connie Luo, R.N., Ted Wu, M.D., Ph.D., Stephen M. Twigg, M.D., Ph.D., Dennis K. Yue, M.D., Ph.D., Jencia Wong, M.D., Ph.D. Long-Term Complications and Mortality in Young-Onset Diabetes. Diabetes Care 2013; 36(12): 3863-3869.
- Gilad Twig, M.D., Ph.D., Gal Yaniv, M.D., Ph.D., Hagai Levine, M.D., M.P.H., Adi Leiba, M.D., M.H.A., Nehama Goldberger, M.Sc., Estela Derazne, M.Sc., Dana Ben-Ami Shor, M.D., Dorit Tzur, M.B.A., Arnon Afek, M.D., M.H.A., Ari Shamiss, M.D., M.P.H., Ziona Haklai, M.A., Jeremy D. Kark, M.D., Ph.D. Body-Mass Index in 2.3 Million Adolescents and Cardiovascular Death in Adulthood. The New England Journal of Medicine 2016; 374:2430-2440.
- Jonathan Pearson-Stuttard, B.M.B.Ch., Bin Zhou, M.Sc., Vasilis Kontis, Ph.D., James Bentham, Ph.D., Marc J Gunter, Ph.D., Majid Ezzati, F.Med. Sci. Worldwide burden of cancer attributable to diabetes and high body-mass index: a comparative risk assessment. The Lancet 2018; 6(6): e6-e15.
- Ye He, Ph.D. , Jing Tian, Ph.D. , Wendy H. Oddy, Ph.D. , Terence Dwyer, M.D., Alison J. Venn, Ph.D. Association of childhood obesity with female infertility in adulthood: a 25-year follow-up study. Fertility and Sterility 2018; 110(4)P596-604.e1.