Childhood obesity is an urgent and complex problem, and its relationship with poor sleep poses a major public health challenge. Adequate sleep is a critical foundation for good health in general.
Poor sleep quality and short sleep duration are linked to being overweight and obese in children as well as adults. Childhood and adolescent obesity have been associated with significant complications, including obstructive sleep apnea, asthma, type 2 diabetes mellitus, hypertension, abnormal lipid levels, liver disease, and depression.
Since childhood obesity is linked to adult obesity, identifying and treating modifiable factors like sleep issues is critical. In this article, I highlight the impact of sleep on childhood obesity. Note that these points also apply to adults!
How does poor sleep contribute to obesity?
Based on the National Sleep Foundation, sleep needs vary by age. Infants need 12-16 hours, 1-2-year-olds need 11-14 hours, preschool kids need 10-13 hours, school ages 9-11 hours, and teens need 8-10 hours of sleep.
Most children in the US get less than the recommended sleep hours, with 57 percent of middle school kids and 73 percent of high school kids getting inadequate sleep.
Short sleep duration is associated with a high risk of being overweight or obese. In addition, a meta-analysis (an extensive analysis of several research studies) of 22 studies showed that short sleepers had over 2 times increased risk of being overweight or obese.
There are four ways poor sleep leads to obesity,
Changes in hormone regulation: Poor sleep can lead to changes in hormone regulation and increased calorie consumption. Two hormones regulate our appetite; leptin, and ghrelin. Ghrelin is a hunger hormone that lets us know we are hungry. Poor sleep patterns and inadequate sleep causes decreased leptin and increased ghrelin, leading to increased eating. Poor sleep can also cause changes in our body’s cortisol level, leading to increased stress and inflammation.
Changes in diet quality: Short sleep duration leads to unhealthy diet habits, including more significant portions, increased perceived hunger, and higher calorie choices, including sugary foods. In a survey of over 2000 4th and 7th graders with insufficient sleep, there was more frequent soda consumption and fewer vegetables.
Decreased physical activity and motivation: When children have poor sleep, they tend to be more physically inactive, have more sedentary lifestyles, and reduced motivation which can lead to weight gain. This is particularly more common in older children. For example, a study on sleep duration in kids showed that those with insufficient sleep were likely to not meet the physical activity guidelines of 60 minutes per day. Instead, these children spent more time watching TV, using screens, and snacking.
Increased food intake to fight fatigue: Sometimes, to counter the fatigue, children (and adults) with sleep loss try to make up with increased caloric intake, which may not necessarily be driven by hormonal changes.
While most studies focus on sleep duration, sleep quality, and timing can also contribute to obesity.
Sleep timing and obesity
Our circadian rhythm (or internal clock) plays a significant role in our hormonal and metabolic health. Our teens and young adults experience