By Robin Allen MSPH, RDN, LDN
We are still discussing the epidemic of chronic diseases; hypertension, type 2 diabetes and now obesity. Particularly we will look at childhood obesity. The increasing prevalence of obesity in all ages is a common thread which runs through all of these conditions.
September is Childhood Obesity Awareness Month! That we even need such a month is shocking and alarming to me. When I was growing up I don’t remember any obese children. Now as a sometimes substitute public school teacher, I am amazed at how many children and teens are overweight or obese. How did we get to this point? What are the causes of childhood obesity? What can we do as dietitians and parents to prevent childhood obesity?
The prevalence of obesity in children has more than tripled from 1971 to 2011. Recent information from the National Center for Health Statistics indicates the childhood obesity rate may finally be reaching a plateau. However, the prevalence is still high among children and adolescents. According to the American Heart Association (AHA), one in three children and teenagers are obese or overweight.
Obesity in children is causing health problems that used to be reserved for only adults. High blood pressure, type 2 diabetes, and elevated cholesterol are all on the rise in children and teens. Obese children are more likely to have low self-esteem, depression, become victims of bullies and a possess a negative self-image leading to psychological and social issues.
How do we determine overweight or obese in children?
Body mass index (BMI) is a measure used to determine childhood overweight and obesity. Overweight is defined as a BMI at or above the 85th percentile and below the 95th percentile for children and teens of the same age and sex. Obesity is defined as a BMI at or above the 95th percentile for children and teens of the same age and sex. For children and teens, BMI is age- and sex-specific and is often referred to as BMI-for-age. A child’s weight status is determined using an age- and sex-specific percentile for BMI rather than the BMI categories used for adults. Children’s body composition varies as they age and varies between boys and girls; therefore, using adult BMI based on height and weight is not accurate. BMI levels need to be expressed relative to other children of the same age and sex. The Center for Disease Control (CDC) has an online BMI calculator for children which is easy to use.
What are the causes of this increased prevalence of childhood obesity? The cause is not totally clear, but the following are factors associated with this increase:
- Sedentary lifestyle: Studies have shown that children who watch television for longer than one hour per day tend to have a higher BMI as well as higher blood pressure. Watching television frequently leads to snacking and poor food choices.
- Decline in physical education and overall activity: Budgetary pressures on schools and increased focus on academic scores have pushed out physical education and recess. Children are spending more time in the car, being driven to school and other activities rather than walking. Working parents are not comfortable with their children going outside when they are not home.
- High-calorie foods and sweetened beverages: Making poor nutrition choices with calorie-dense foods and the intake of sweetened beverages. Studies have shown an association between sugared beverage intake and obesity, in both children and adults. This includes both soft drinks and sugar-sweetened fruit drinks.
- Large portion sizes:An increase in portion sizes, for instance, has been linked to increased obesity in children, particularly among adolescents. Portion sizes have increased since the 1970’s.
- Eating away from home:There is evidence that eating away from home, usually “fast food” is associated with increased risk for overweight and obesity.
- Parental obesity: A genetic component to obesity cannot be ignored, as obesity has been found to be inherited in certain families. Genetics plays a big role in obesity. Some studies suggest up to 25% to 40 % of BMI is inherited.
- Excess weight gain during pregnancy. In Boston, Project Viva, found that children of women who gained an excessive amount of weight had more than four times the risk of being overweight at age 3 compared to children of women who gained less weight. Many women are also heavier when they become pregnant.
- Gestational Diabetes:This may subject the fetus to periods of high blood glucose and elevated insulin leading to increased body fat and larger size at birth.
- Low birth weight: < 2500 gm is a risk factor for overweight or obesity in children and teens.
- Infant weight gain: Rapid weight gain in the first weeks or months of life has been associated with a higher BMI and obesity later in life.
- How long an infant is breast fed: Breast feeding has been associated with a 13 percent and 22 percent reduced risk of obesity later in life. It is not clear if breast feeding actually prevents obesity, but breast feeding has been associated with higher socioeconomic status and other cultural factors. Another factor is that breast feeding provides an infant with greater self-regulation than bottle feeding.
- Infant sleep: Infants who slept less than 12 hours per day doubled the odds of becoming overweight at age 3 compared to infants who slept more than 12 hours per day. Shorter infant sleep duration can be influenced by maternal depression during pregnancy, solid foods introduced prior to 4 months and infant TV viewing.
- Parental eating and physical activity habits: Parents influence a child’s eating behavior and activity levels.
- Demographics: Low-income, African American, and Hispanic children are more likely to be overweight.
- Parenting style: Some researchers believe that excess parental control over children’s eating may lead to poor self-regulation.
Although progress has been made in the prevention and treatment of childhood obesity it is still a complex problem which requires a multilevel multi-systems approach. The parents, schools, food manufacturers, infrastructure, physicians, dietitians, all health care and child care providers must be involved. While there are many programs trying to combat childhood obesity, 5-2-1-0 Let’s Go! is a nationally recognized childhood obesity prevention program that has been implemented successfully around the country. The goal is to increase physical activity and healthy eating from birth to age 18. Learn more about this program and register for the free webinar 5-2-1-0 Healthy Messaging Campaign at the event page.
D.M. Hoelscher, S. Kirk, L. Ritchie, L. Cunningham-Sabo, Position of the Academy of Nutrition and Dietetics: Interventions for the Prevention and Treatment of Pediatric Overweight and Obesity. Jn of the Academy of Nutrition and Dietetics vol. 113:10 (Oct 3, 2013)
This post was written by Robin Allen, a member of the Military Families Learning Network (MFLN) Nutrition and Wellness team which aims to support the development of professionals working with military families. Find out more about the MFLN Nutrition and Wellness concentration on our website, on Facebook, on Twitter and on LinkedIn.