SAN FRANCISCO – Obesity is a multifactorial problem, influenced by factors ranging from genetics to lifestyle to the environment. Yet stress can play an outsize role in obesity as well, Elizabeth Prout Parks, MD, said at the annual meeting of the American Academy of Pediatrics.
Although the calorie-in/calorie-out model of energy balance has driven much of the thought about obesity, it’s not that simple, suggested Dr. Parks, the medical director of the Healthy Weight Adolescent Bariatrics Program at the Children’s Hospital of Philadelphia. Physical activity accounts for an estimated 15%-30% of energy expenditure, and thermogenesis accounts for an estimated 10%. But the energy expenditure required for basal metabolism can range from 60% to 75%, a sufficiently wide range for significant variation across different individuals.
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The psychosocial effects can lead to anxiety, depression, disordered eating behaviors such as emotional eating, a sedentary lifestyle, poor sleep, and low maintenance with self-care activities. Further, poor sleep on its own is additionally associated with childhood obesity. The combination of these physiologic and psychosocial effects can increase the risk of metabolic syndrome, type 2 diabetes, and cardiovascular disease or events. While acute stress and chronic stress follow similar pathways in the brain, it’s chronic stress that carries the greater risk of behavioral and physical conditions.
Measuring and understanding child and parental stress
Several clinical assessments can measure stress in children, including the Daily Hassles Scale, which looks at everyday interactions in the environment and factors such as children’s school, family, neighborhood, peers, and lack of resources. The Multidimensional Life Events Rating Questionnaire and Adolescent Stress Questionnaire both are more appropriate for middle school and older adolescents.
In children, the primary biologic indicators of stress are cortisol levels, heart rate, and blood pressure, but it is perceived stress that has been most clearly linked to emotional eating and other disordered eating behaviors, Dr. Parks said. One 2008 study found perceived stress to be associated with emotional eating among middle school students both with and without obesity. A high level of perceived stress in adolescents was associated with a greater waist circumference and body mass index in a 2009 study.
The findings are somewhat more mixed, however, when it comes to parental stress and child weight. A 2012 study identified a link between parents’ perception of their stress and increased fast food consumption in their children, and a 2008 study identified a link between parenting stress and both overweight and underweight children. Yet a different study in 2008 found no association between child obesity and parenting stress. Research in 2011 found a relationship between children’s consumption of fruits and vegetables and their family’s overall functioning, as well as parental psychological stress and child behavior. Within a family, stress can come from financial strain (such as poverty or changes in employment or insurance), the family’s structure, and changes in physical or mental health of one or more family members.
Addressing the effects of stress on diet
Clinicians can help families manage the ways stress can lead to obesity by helping them with ideas for increasing fruit and vegetable intake, and planning ahead for on-the-go eating. For example, to ensure children get in their recommended five servings of fruit and vegetables each day, parents can serve fruit with breakfast every day and offer vegetables and/or fruit as a snack. Including side salads and a frozen vegetable with dinner will add two more servings, and children can munch on chopped veggies while parents prepare dinner. Offering fruit as a dessert provides another opportunity to bump up kids’ fruit and veggie intake, Dr. Parks said.
To manage the risk of unhealthy eating when out and about, Dr. Parks recommends planning ahead by packing a snack such as yogurt, fruit and vegetables, a sandwich or wrap, and water.
She described the “apple test” for determining whether someone is eating because of boredom or stress or because of actual hunger.“The next time you are thinking about a mini meal or second helpings at a meal, ask yourself, ‘Would I eat an apple instead?’ ” Dr. Parks said. “If the answer is no, then you probably are not really hungry and just need to get away from food.”
Other things people can consider when about to eat something are whether they are actually hungry and whether a distraction such as the television is contributing to distracted eating. “People may eat when they’re happy, sad, or bored,” Dr. Parks said, noting that outside messages such as commercials, advertisements, and passing restaurants may make someone feel like eating even if they don’t need sustenance at that moment. “Consider whether you really are hungry before you eat,” she said.