Heavy television viewing has been associated with obesity. Television might lead to obesity through 3 primary pathways:
1) Displacing time that would otherwise be spent in physical activity
2) Promoting eating while viewing, which may foster both lower-quality and higher-quantity food intake;
3) Exposing children to food advertising, this adversely affects their diets.
Studies have shown that the third pathway of food advertising has the most impact on causing children to be overweight. Randomized experiments with children in preschool and ﬁrst grade have shown that children experimentally exposed to a few commercials are more likely than unexposed children to have positive attitudes toward and to choose the advertised foods over alternatives. Furthermore, one study found that children exposed to advertising were also more likely than were participants in a control group to choose non advertised sugary foods. The effect of the advertising was thus not limited to the speciﬁcally advertised brands but had a more general adverse inﬂuence on their food choices
Marketers target very young children, and children start watching television at very young ages. Almost 90% of children begin watching television regularly before age 2, and the average age of initiation is 9 months. Marketing efforts begin with children as young as 2 years, in order to build brand awareness and brand sympathy. The typical ﬁrst-grade child can already recognize and respond to more than 200 brands.
Research tells us that food advertising is highly effective. Food commercials increase children’s preferences for the advertised products and make kids more likely to ask their parents to buy the products for them. Marketers know this and spend billions of dollars a year on advertising campaigns targeted to children. One study found that children between the ages of eight and twelve years old see, on average, more than 7,600 food commercials every year. Food advertising wouldn’t be such a problem if most of the products being marketed were nutritious, but, unfortunately, that’s not the truth. Commercials for candy, snacks and fast food account for more than half of all food ads targeted to children and teenagers, and commercials for fruits and vegetables are almost nonexistent.
In 2003, the World Health Organization classified the marketing of unhealthy foods to children as a probable cause of childhood obesity. Eating while watching television is another likely reason why TV viewing can lead to obesity. More than 60% of children usually eat their meals with the TV on, and children regularly snack while watching TV. Research also suggests that children eat less healthy foods in front of the TV. For example, one study found that children eat more salty snacks and fewer fruits and vegetables when they eat with the TV on. In addition to affecting the types of foods children eat, television has an impact on how much food they consume. Kids tend to eat more food while watching TV than during other activities. Researchers have proposed that watching TV interferes with our bodies’ signals that we’re full. In other words, children become so engrossed in what they’re watching that they don’t realize they’ve had enough to eat.
The use of television during family dinners has also been examined. Family dinners without television have been shown to be beneﬁcial to the diets of children and adolescents and have been associated with the likelihood of consuming ﬁve or more servings of fruits and vegetables daily Increased frequency of consuming family dinners was also associated with signiﬁcantly higher intakes of several nutrients, including ﬁber, calcium, folate, iron, vitamins B6, B12, C, and E; and lower intake of saturated and trans fatty acids as a percentage of energy.
In a longitudinal study, family meals during adolescence predicted higher intakes of fruits, vegetables, many important nutrients and an overall higher quality diet in young adulthood. Studies have shown that when television is on during family dinners, the positive nutritional consequences of eating together are reduced. For example, in a cross-sectional study, they found that in children of low-income families, servings of fruits and vegetables eaten were inversely correlated with the number of times per week the television was on during dinner. Other research conﬁrmed that in parents, when the television was on during dinner, intake of fat increased, whereas servings of fruits and vegetables decreased. As parents are the gatekeepers of food provided to children, it stands to reason that parental eating behavior will impact children. These studies add further to the idea that diet quality is threatened by television, speciﬁcally when it is viewed during meal times. It's also reported that children who frequently ate while watching television had a preference for larger portions of energy dense, nutrient-poor foods.