The average American watches about four hours of television per day, a habit that's been linked to overweight or obesity in a number of studies. Data from the National Health and Nutrition Examination Survey, a long-term study monitoring the health of American adults, revealed that people with overweight and obesity spend more time watching television and playing video games than people of normal weight.
Watching television more than two hours a day also raises the risk of overweight in children, even in those as young as three years old. Part of the problem may be that people are watching television instead of exercising or doing other activities that burn more calories watching TV burns only slightly more calories than sleeping, and less than other sedentary pursuits such as sewing or reading.
But food advertisements also may play a significant role. The average hour-long TV show features about 11 food and beverage commercials, which encourage people to eat. And studies show that eating food in front of the TV stimulates people to eat more calories, and particularly more calories from fat. In fact, a study that limited the amount of TV kids watched demonstrated that this practice helped them lose weight — but not because they became more active when they weren't watching TV.
The difference was that the children ate more snacks when they were watching television than when doing other activities, even sedentary ones. Obesity experts now believe that a number of different aspects of American society may conspire to promote weight gain. Stress is a common thread intertwining these factors. For example, these days it's commonplace to work long hours and take shorter or less frequent vacations.
In many families, both parents work, which makes it harder to find time for families to shop, prepare, and eat healthy foods together. Round-the-clock TV news means we hear more frequent reports of child abductions and random violent acts.
This does more than increase stress levels; it also makes parents more reluctant to allow children to ride their bikes to the park to play. Parents end up driving kids to play dates and structured activities, which means less activity for the kids and more stress for parents. Time pressures — whether for school, work, or family obligations — often lead people to eat on the run and to sacrifice sleep, both of which can contribute to weight gain. Some researchers also think that the very act of eating irregularly and on the run may be another one of the causes of obesity.
Neurological evidence indicates that the brain's biological clock — the pacemaker that controls numerous other daily rhythms in our bodies — may also help to regulate hunger and satiety signals. Ideally, these signals should keep our weight steady.
They should prompt us to eat when our body fat falls below a certain level or when we need more body fat during pregnancy, for example , and they should tell us when we feel satiated and should stop eating. Close connections between the brain's pacemaker and the appetite control center in the hypothalamus suggest that hunger and satiety are affected by temporal cues.
Irregular eating patterns may disrupt the effectiveness of these cues in a way that promotes obesity. Similarly, research shows that the less you sleep, the more likely you are to gain weight.
Lack of sufficient sleep tends to disrupt hormones that control hunger and appetite and could be another one of the causes of obesity. In a study of more than 1, volunteers, researchers found that people who slept less than eight hours a night had higher levels of body fat than those who slept more, and the people who slept the fewest hours weighed the most.
Stress and lack of sleep are closely connected to psychological well-being, which can also affect diet and appetite, as anyone who's ever gorged on cookies or potato chips when feeling anxious or sad can attest.
Studies have demonstrated that some people eat more when affected by depression, anxiety, or other emotional disorders. In turn, overweight and obesity themselves can promote emotional disorders: If you repeatedly try to lose weight and fail, or if you succeed in losing weight only to gain it all back, the struggle can cause tremendous frustration over time, which can cause or worsen anxiety and depression.
A cycle develops that leads to greater and greater obesity, associated with increasingly severe emotional difficulties. As a service to our readers, Harvard Health Publishing provides access to our library of archived content.
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Overview Obesity is a complex disease involving an excessive amount of body fat. Request an Appointment at Mayo Clinic. Share on: Facebook Twitter.
Show references Overweight and obesity. National Heart, Lung, and Blood Institute. Accessed May 3, Goldman L, et al. In: Goldman-Cecil Medicine. Elsevier; Kellerman RD, et al. Obesity in adults. In: Conn's Current Therapy Feldman M, et al. Perrault L. Obesity in adults: Prevalence, screening and evaluation. Melmed S, et al. In: Williams Textbook of Endocrinology. And it is hitting poorest communities the hardest. In New York City neighborhoods like Brownsville, two out of every three children are overweight.
These children live in a community where rates of teen pregnancy, homelessness, incarceration and domestic violence are among the highest in the city. And the mortality rates here from diabetes, cardiovascular disease and H. Children have few safe places to play and parents have few places to buy fresh fruits and vegetables. This article lists 9 compelling reasons why obesity is not just a choice. Share on Pinterest. Genetics and prenatal factors.
Birth, infancy, and childhood habits. These include childbirth method, breastfeeding, and childhood dietary and exercise habits. Medications or medical conditions. Many medical conditions can only be treated with pharmaceutical drugs.
Powerful hunger hormones. Hunger and uncontrollable eating are not just caused by greediness or lack of willpower. These hormones often function improperly in people with obesity, which causes a strong physiological drive to eat more, resulting in weight gain. Leptin resistance. This causes a powerful physiological drive to eat more. Poor nutrition education. Addictive junk food. This is more common than you may think. The effect of gut bacteria. Many studies show that these bacteria are incredibly important for overall health.
This may cause people with obesity to store more fat. The environment. SUMMARY Several environmental factors can make you more susceptible to obesity, including living in a food desert and exposure to artificial light.
The bottom line. Read this next.
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