George Antonogeorgos
and Demosthenes Panagiotakos
Key Points
• An unbalanced diet is a very important risk factor for several chronic diseases such as obesity, stroke, cancer, and type 2 diabetes mellitus.
• Television (TV) viewing and video gaming have emerged as signifi cant factors contributing to the current obesity epidemic and the correspond- ing low diet quality.
• The assessment of diet quality is performed with the assessment of the necessary micro- and macronutrient elements in children’s and adoles- cents’ diet or with the use of composite health quality indices.
• Children are more prone to poor diet quality which is attributed to the vulnerability of their developmental phase to food advertising on TV and also to the poor diet quality of their parents or caregivers.
• In adolescence, besides food advertising, snacking while watching TV plays also a signifi cant role in poor diet quality food choices.
• Another possible way in which TV may infl uence fast food intake is through hidden food consuming messages embedded within program content.
• Important food markers for assessing the relation between TV watching and poor diet quality are snacks and soft drinks or sugar-added beverages.
• Video gaming has emerged as a rapidly evolving favorite screen-related activity in childhood recently and its effect on diet quality is poorly studied.
• Video gaming has been positively related with food overconsumption and increased caloric intake, indicating an association with poor diet quality choices.
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Abbreviations
AMQI Adolescent Micronutrient Quality Index
DQI Diet Quality Index
DQI-I Diet Quality Index-International HEI Healthy Eating Index
TV Television
USA United States of America
USDA Department of Agriculture of the USA WHO World Health Organization
Introduction
An unbalanced diet is a very important risk factor for several chronic diseases such as obesity, stroke, cancer, and type 2 diabetes mellitus.
These diseases are contributing to the rise of the proportion of preliminary deaths, to the limita- tion of general life quality and are considered as major public health problems. Thus, it is of pri- mary importance to monitor the population’s diet and to help improve dietary habits by providing the necessary nutritional information and the cor- responding education. Moreover, it is vital to identify groups or individuals whose consump- tion of certain nutrients is systematically too high or too low and their diet quality is characterized as poor. These individuals are in greater danger of developing nutrient-related conditions, thus early recognition of the population in danger could lead to interventions that could prevent the arise of such pathology.
Time spent engaged in sedentary behaviors, such as television (TV) viewing and video gam- ing, is considered to be one of the factors underly- ing the increasing prevalence of overweight and obesity observed around the world [ 1 ]. Positive relations between TV viewing and adiposity are constantly found, with several studies reporting the fact that men and women watching the most TV have a 2–4-fold increased risk of obesity com- pared with those watching the least TV [ 2 , 3 ].
Video games have vast mass call and are pres- ent in the daily schedule of most children and
teenagers. As of 1999, video games account for approximately 30 % of the USA toy market, which helped the video game industry to earn between $6 and $9 billion, thus making more profi t than even the motion picture industry [ 4 ].
A 2004 estimate of media consumption showed that video game play and nonschool-related com- puter access occupy approximately 2 h of a typi- cal child’s day [ 5 ]. The increased prevalence of electronic game play (computer and video games) has alarmed the researchers and urged them to investigate the effect of this media type on vari- ous aspects of health [ 6 ].
The purpose of this chapter is to review the current literature in order to summarize the effect of the aforementioned sedentary activities (TV viewing and video gaming) in the diet quality of children and adolescence. Furthermore, a sum- mary of the indexes of assessing diet quality will be further discussed.
Defi nition and Assessment Methods of Diet Quality
Good nutrition is a very important part of every child’s healthy life. Diet quality refl ects a dietary pattern in accordance with all the necessary micro and macronutrient elements needed to maintain health and to support growth and development. As a reference value, the most commonly used in the international literature are the Reference Daily Intake Tables used from the Department of Agriculture of the USA (USDA) [ 7 ].
Diet quality indices are often used to provide a summary of diet quality rather than observing single food and nutrient items [ 8 ]. There are sev- eral indexes proposed for assessing diet quality in various age groups which are summarized in Table 13.1 . The Revised Children’s Diet Quality Index (DQI) has been developed by Kranz et al., using the USA dietary recommended intake guidelines for preschool-aged children (aged 2–5 years old). This index evaluates 12 dietary com- ponents (added sugar, total fat, linoleic and linolenic fatty acids, docosahexaenoic acid,
G. Antonogeorgos and D. Panagiotakos
eicosapentaenoic acid, total grains, whole grains, vegetables, fruits, 100 % fruit juice, diary and iron intake) as well as total energy intake and television time spent with an interaction term [ 8 ].
For the same age group another DQI had been developed as a tool for assessing the compliance of Flemish preschoolers with the Flemish Food- Based Dietary Guidelines for preschool children.
This index consists of four major components:
dietary diversity (eight food groups), dietary quality (preferred foods within a food group are given higher scores), dietary equilibrium (higher scores if adequate but moderate intake of each food element is reassured), and meal index (num- ber of main meals per day). The DQI has been validated by comparing the DQI scores derived from 3 days’ records with nutrient intake profi les and has been found to be a reliable quality index [ 9 ]. An index that was not specifi cally developed for children but can be applied to them, the
Table 13.1 Summary of the main indices used in the diet quality research in children and adolescents Health index Components
The Revised Children’s Diet Quality [ 8 ]
Added sugar Total fat
Linoleic and linolenic fatty acids docosahexaenoic acid
Eicosapentaenoic acid Total grains
Whole grains Vegetables Fruits
100 % fruit juice Diary and iron intake Diet Quality
Index (DQI) [ 9 ]
Dietary diversity (eight food groups) Dietary quality (preferred foods within a food group are given higher scores) Dietary equilibrium (higher scores if adequate but moderate intake of each food element is reassured)
Meal index (number of main meals per day)
Healthy Eating Index (HEI) [ 10 ]
Total and whole fruit Total vegetables
Dark, green and orange vegetables and legumes
Total and whole grains Milk
Meat Beans
Oils and calories from solid fats Alcoholic beverages
Added sugars Saturated fats Sodium Adolescent
Micronutrient Quality Index (AMQI) [ 12 ]
Cereals and millets Legumes
Milk and milk products
Vegetables (green leafy vegetables, other vegetables, roots and tubers) Fruits
Sugar
Fats/oils (visible)
At least 50 % grains as whole grains At least 50 % legumes being micronutrient-dense
Food variety based on all subgroups and weekly variety in vegetables and fruits
Sprouts/fermented foods/salads Tea/coffee with meals Fried foods
(continued)
Health index Components Diet Quality
Index- International (DQI-I) [ 13 ]
Variety
Overall food group variety Within-group variety from protein source
Adequacy Vegetable group Fruit group Grain group Fiber Protein Iron Calcium Vitamin C Moderation Total fat Saturated fat Cholesterol Sodium
“Empty calorie food”
Overall balance Macronutrient ratio (carbohydrate:protein:fat)
Fatty acid ratio (PUFA + MUFA/SFA)
PUFA polyunsaturated fatty acids, MUFA monounsatu- rated fatty acids, SFA saturated fatty acids
Table 13.1 (continued)
164
Healthy Eating Index (HEI), was revised in 2005 after the publication of the 2005 Dietary Guidelines in order to measure diet quality in terms of compliance with the key diet-related recommendations of the 2005 Dietary Guidelines.
The components of the HEI include all the major food groups (total and whole fruit, total vegeta- bles, dark, green and orange vegetables and legumes, total and whole grains, milk, meat, beans, oils and calories from solid fats, alcoholic beverages, added sugars, saturated fats, and sodium) [ 10 ]. A modifi ed version of the previous HEI designed to assess diet quality in children aged 9–14 years of age had also been published [ 11 ]. Also diet quality indexes for specifi c popu- lation has been formulated, like the Adolescent Micronutrient Quality Index (AMQI) for assess- ing the micronutrient adequacy in adolescent girls consuming a lacto-vegetarian diet [ 12 ] and the Mediterranean adaptation of the Diet Quality Index-International (DQI-I) [ 13 ].
Since validated diet quality indexes are lack- ing from the literature, research has focused on the consumption of specifi c food groups or nutri- ents, as a proxy to the overall children’s diet qual- ity. The selection of these food groups and nutrients is based on the previous knowledge about the protective or un-protective effect in various aspects of childhood or adult life. For example, sugar-sweetened beverage intake is associated with weight gain in children [ 14 , 15 ].
Also, calcium intake is associated with decreased blood pressure among children as well as increased bone mineral density among them [ 16 , 17 ]. Fruit and vegetables may play a protective role against the development of cancer and coro- nary heart disease while trans - and saturated fat consumption has a negative association with it [ 18 , 19 ]. However, the approach of assessing single nutrients or food items, instead of assess- ing dietary patterns, could introduce some bias since children do not consume isolated nutrients, but eat meals consisting of a variety of foods with complex combinations of nutrients. This way of dietary assessment is indicated when there is lack of age-appropriated, validated diet quality indexes to capture the whole eating patterns and is often observed in recent studies .
TV Viewing and Diet Quality
in Childhood and Young Adulthood Up to 17 years of age, a US child has spent more hours in watching television than going to school (15,000–18,000 compared to 12,000 h). Thus, TV viewing has been connected early to the vari- ous aspects of children’s diet patterns. Table 13.2 summarizes several studies regarding the associ- ation of TV viewing with diet quality during childhood. The focus of the studies in this age group is attributed to the venerability of this developmental phase to food advertising on TV.
There is evidence supporting that TV watching is closely related to snacking and their snacking preferences are most of the time affected by advertised foods which are more likely to have high concentrations of fat, sugar, and sodium [ 20 ]. Batada et al. have reported that 91 % of food advertisements during Saturday morning children’s television programming in the USA were for foods or beverages high in fat, sodium, or added sugars or were low in nutrients and 18 % of food advertisements were about snack foods [ 21 ]. Moreover, children exposed to food advertisements are more prone to request that their parents purchase the dietary products that are most advertised [ 22 , 23 ]. Exposure to as little as one or two times to short food commercials is enough to alter a preschool-age child’s food pref- erences [ 24 ]. During the development of eating patterns the role of environment has a great infl u- ence. Children become developmentally capable of making the transition to family foods, after the age of one and their internal regulatory mecha- nism for hunger and satiety is infl uenced by cul- tural patterns. The preschool period is essential to the origins of healthy eating patterns and due to the sensitivity of the developmental immaturity of children it is being thoroughly investigated by the researchers. Also young children’s TV and eating habits often refl ect those of their parents or caregivers. For instance, children who watch greater amounts of TV may do so because those caring for them may frequently watch TV.
Therefore, the association we found between young children’s television/video viewing and
G. Antonogeorgos and D. Panagiotakos
Table 13.2 Summary of studies assessing TV viewing and diet quality in childhood and young adulthood
Study Study design Sample Exposure Estimates of association
Miller et al.
(2008) [ 30 ]
Cross-sectional 3-Year-old 613 boys 590 girls from USA
1 h TV viewing per day
0.06 servings/day [95 % CI 0.03, 0.10] for sugar-sweetened beverages
0.32 servings/month [95 % CI 0.16, 0.49] for fast food 0.06 servings/day [95 % CI 0.02, 0.09] for red/processed meat 48.7 kcal/day [95 % CI 18.7, 78.6] for total energy intake 0.05 [95 % CI 0.03, 0.07] for % energy intake from trans −0.18 servings/day [95 % CI
−0.32, −0.05] for fruits and vegetables
24.6 mg/day [95 % CI −41.0,
−8.1] for calcium
−0.44 g/day [95 % CI −0.65,
−0.22] for dietary fi ber Taveras et al.
(2006) [ 37 ]
Cross-sectional 2–6 years old 240 parents of children USA
1 h increase of TV/
video watched per day
Adjusted OR for consuming fast food ≥1 time per week: 1.55 (95 % CI, 1.04–2.31) Parvanta et al.
(2010) [ 33 ]
Cross-sectional 6–18 years old
n = 1,552 China
TV watching hours per week Reported paying attention to
TV commercials (yes vs. no)
aOR: 1.00; 95 % CI = 0.98–1.02 per TV watching hour for requesting snacks seen on TV aOR: 3.42; 95 % CI = 2.55–4.60 of requesting snacks seen on TV when children paid attention to the commercials
aOR 1.60; 95 % CI = 1.23–2.07 for eating snacks seen on TV when children paid attention to the commercials
Liang et al.
(2011) [ 39 ]
Cross-sectional 11 years old students n = 4,966 Canada
Hours of television watching (1–2 h/d, 3–4 h/d, ≥5 h/d vs.
<1 h/d)
OR for soft drinks: 2.46 95 % CI = 1.54–3.93 for ≥5 h/d vs.
<1 h/d Supper in front of
television (1–2 times/
week, 3–4 times/week,
≥5 times/week vs.
<1 time/week)
0.57; 95 % CI 0.24–0.89 % of sugar energy from carbohydrate energy for 3–4 h/d vs. <1 h/d 2.20; 95 % CI 0.29–4.10 % of energy from snack foods for
≥5 h/d vs. <1 h/d
−0.09; 95 % CI = −0.16, −0.03 daily servings of fruits and vegetables for 3–4 h/d vs. <1 h/d −1.73; 95 % CI = −3.35, −0.10 mean difference in Diet Quality Index for ≥5 h/d vs. <1 h/d OR for overweight: 2.42 95 % CI = 1.54–3.79 for ≥5 h/d vs.
<1 h/d
(continued)
166
Table 13.2 (continued)
Study Study design Sample Exposure Estimates of association
Manios et al.
(2009) [ 41 ]
Cross-sectional 1–5 years old
n = 2,374 Greece
≥2 h/d watching TV vs.
≤2 h/d
46.5; 95 % CI = 12.2–80.8 kcal of total energy intake
OR: 1.31; 95 % CI = 1.00–1.69 of
≥5 exchanges of fat
OR: 1.51; 95 % CI 1.14–2.00 of exchanges of meat
OR: 1.31; 95 % CI 1.01–1.67 if exchanges of other carbohydrate Dubois et al.
(2008) [ 42 ]
Longitudinal Birth to 4.5 years of age
n = 2,013 Canada
Frequency of eating while watching TV (meal or lunch using eat while-TV- watching index)
OR: 3.57; p < 0.05 for drinking soft drinks when eating snacks while watching TV every day vs.
never
OR:2.34; p < 0.05 for drinking soft drinks while eating when watching TV three of four times daily vs. less than once daily
Jackson et al.
(2009) [ 58 ]
Cross-sectional 2–6 years n = 89 UK
1 h watching TV per day
1.095 kg increase in weight per extra hour of TV viewing Jago et al.
(2005) [ 43 ]
Cohort Start age:
3–4 years n = 149 Follow-up time:
3 years USA
Minutes of TV per day Beta = 0.046 kg/m 2 ( p < 0.001) increase in per minute increase of TV watching
Fieldman et al.
(2007) [ 34 ]
Cross-sectional Mean age:
14.9 years
n = 4,746 USA
Watch TV while eating family meals
1.3 median daily servings of vegetables for family meals with TV vs. 1.4 with no TV, p < 0.001 0.40 median daily servings of dark green/yellow vegetables for family meals with TV vs. 0.43 with no TV, p < 0.001 5.1 median daily servings of grains for family meals with TV vs. 5.3 with no TV, p = 0.02 0.56 median daily servings of fried foods for family meals with TV vs. 0.54 with no TV, p < 0.001 2.4 median daily servings of snack food for family meals with TV vs. 2.2 with no TV, p = 0.002 Fitzpatrick et al.
(2007) [ 61 ]
Cross-sectional 1–4 years n = 1,478 USA
Number of days per week the television was on during dinner
aOR = 0.95; 95 % CI 0.91–0.99 for serving fruits per night of watching television with dinner aOR = 0.94; 95 % CI 0.90–0.98 for serving vegetables per night of watching television with dinner
(continued) G. Antonogeorgos and D. Panagiotakos
Table 13.2 (continued)
Study Study design Sample Exposure Estimates of association
Francis et al.
(2006) [ 59 ]
Experimental 3–5 years old preschoolers
n = 24 USA
(a) 22-min cartoon video on TV (b) Parental reporting of
children’s eating during TV viewing at home
Signifi cant higher intake for both snack and lunch meals in the no TV condition in the experimental condition ( t (24) = 3.1, p < 0.01 and t (24) = 4.2, p < 0.001, respectively) Signifi cant higher intake for lunch intakes ( r = 0.56, p < 0.05) for children reported watching more daily hours of TV at home Francis et al.
(2003) [ 44 ]
Longitudinal Start age:
5-year-old girls Assessment: at 7 and 9 years of age
n = 173 USA
Hours of watching TV per day
Beta = 0.30 kg/m 2 ( p < 0.001) for BMI at age 9 in girls with at least one overweight parent
Boynton-Jaret et al. (2003) [ 31 ]
Cohort Mean start age:
11.7 years Follow-up time = 19 months
n = 548 USA
Hours of watching TV per day
Mean reduction of daily fruit and vegetables consumption: 0.14 serving/day per additional hour of television viewed, adjusted for several confounders
Wiecha et al.
(2006) [ 45 ]
Cohort Mean start age:
11.7 years Follow-up time = 18 months
n = 548 USA
Hours of watching TV per day
Mean increase in all foods commonly advertised on television (FCAT-soft drinks, fried foods, and snacks): 0.60 servings/
day per 1 h/d increase ( p = 0.001) Vereecken et al.
(2007) [ 40 ]
Cross-sectional 11–15 years old
n = 162,305 children Several countries from Europe, USA, and Israel
Hours of watching TV per day
Statistically signifi cant increase for the effect of TV viewing to the daily consumption of soft drinks, sweets and decrease in the daily consumption of vegetables and fruit
Pearson et al.
(2011) [ 28 ]
Longitudinal Start age: 12–15 years old (T1) Follow-up time = 2 years (T2) n = 1,729 Australia
Eating snacks while watching TV
Beta: 0.26; 95 % CI (0.21–0.31) for energy-dense snack consump- tion in T2 when adolescents eating snacks while watching TV Beta: 0.14; 95 % CI (0.09–0.20) for energy-dense drink consump- tion in T2 when adolescents eating snacks while watching TV Beta: −0.06; 95 % CI (−0.10 to 0.03) for fruit consumption in T2 when adolescents eating snacks while watching TV
French et al.
(2001) [ 38 ]
Cross-sectional Mean age: 14.9 years n = 4,682 USA
Hours of watching TV on average per weekday and weekend day
More than 3 times/week eating in fast food restaurants was signifi cantly positively associated with weekday television viewing in boys and girls ( p < 0.001) and only with weekend television viewing in girls ( p < 0.001)
(continued)
168
Study Study design Sample Exposure Estimates of association
Barr-Anderson et al. (2009) [ 29 ]
Longitudinal Cohort 1: n = 564 middle school students Cohort 2:
n = 1,366 high school students Follow-up time:
5 years USA
Heavy television viewers (≥5 h/d) vs.
moderate (2–5 h/d) and limited (<2 h/d)
Younger cohort: 1.72 (0.11) fruit servings/d for heavy TV viewers vs. 1.9 (0.07) and 2.06 (0.09) for moderate and limited, respectively ( p = 0.009)
Older cohort: 1.25 (0.07) fruit servings/d for heavy TV viewers vs. 1.60 (0.04) and 1.70 (0.05) for moderate and limited, respectively ( p < 0.001)
Utter et al.
(2006) [ 32 ]
Cross-sectional 5–14 years
n = 3,275 New Zealand
≥2 h/d TV watching vs.
<1–2 h/d or <1 h/d
Aged 5–10 years:
Statistically signifi cant less likely to be high consumers of fruits and vegetables and more likely to be high consumers of soft drinks ( p = 0.029), hamburg- ers ( p = 0.016), and French fries ( p < 0.001) than children watching less than an hour
Aged 10–14 years:
Statistically signifi cant more likely to be high consumers of soft drinks ( p = 0.036), hamburg- ers ( p = 0.018), French fries ( p = 0.003), and chocolate sweets ( p = 0.004) than adolescents watching TV for less than an hour Statistical more likely to be obese ( p = 0.04) than adolescents watching TV for less than an hour Ranjit et al.
(2010) [ 52 ]
Cross-sectional Mean age:
15(1.6) years
n = 15,283 USA
Hours of watching television per day
Statistically signifi cant increase for mean times soda consumption per day ( p < 0.001)
aOR (adjusted) odds ratio, CI confi dence intervals, h / d hours per day Table 13.2 (continued)
poorer diet quality could, in fact, refl ect an asso- ciation between parents’ television viewing and diet quality. Figure 13.1 presents the conceptual framework of the relation between TV watching and low diet quality in children.
The other age group that has been extensively researched is that of adolescents. Adolescence is another critical time during child development in which lifetime behaviors are formed or reshaped and eating patterns developed at this age are more likely to characterize later eating patterns and diet quality [ 25 ]. Adolescents have better cognitive abilities than younger children and they provide better quality information to
researchers. Also the participation of most of the adolescents in schools makes them an easily accessible age group to longitudinal dietary assessment and evaluation. Like younger chil- dren, food advertisement plays a signifi cant role in the negative effect of TV viewing in adoles- cents’ diet quality. Adolescents eat more unhealthy foods such as pizza, hamburgers, snack foods, and soda consistent with the foods advertised on television [ 26 , 27 ]. However, snacking while watching TV is a signifi cant con- tributing factor in mediating the association between television viewing and adolescents’ eat- ing behaviors. Pearson et al. in a longitudinal
G. Antonogeorgos and D. Panagiotakos