Television watching and fatness in children

Predictor factors for childhood obesity in a Spanish case-control study

OBJECTIVE

The aim of this study was to identify and characterize factors associated with childhood obesity risk related to lifestyle and perinatal life influences (dietary pattern, physical activity, family history of obesity, breast-feeding, sedentary behavior, and birth weight) in a case-control study design.

METHODS

Cases were 185 obese (body mass index >97th percentile) children and adolescents (6-18 y old) from the Navarra region of Spain and control subjects were matched by sex and age. Anthropometric data were collected, and a personal interview about lifestyle parameters (dietary patterns, physical activity, family history of obesity, breast-feeding and sedentary behaviors) was performed with each participant. Conditional logistic regression was used to identify predictive factors of obesity.

RESULTS

Leisure time physical activity proved to be a protector factor against obesity (odds ratio [OR] 0.94, 95% confidence interval [CI] 0.92-0.96), whereas family history of obesity (OR 4.18, 95% CI 2.20-8.62), watching television (OR 2.02, 95% CI 1.09-3.77), and sugar-sweetened beverage consumption (OR 1.74, 95% CI 1.05-2.89) were associated with a higher obesity risk.

CONCLUSION

Our results suggest that leisure time physical activity, family history of obesity, watching television, and sugar-sweetened beverage consumption are important predictive variables for childhood obesity, whereas other factors including breast-feeding, birth weight, and time spent sleeping did not appear to play an important role in the development of childhood obesity.

Role of television in childhood obesity prevention

OBJECTIVE

To assess the role of television as tool for childhood obesity prevention.

METHOD

Review of the available literature about the relationship between television and childhood obesity, eating habits and body shape perception.

RESULTS

The reviewed studies showed the following: television watching replaces more vigorous activities; there is a positive correlation between time spent watching television and being overweight or obese on populations of different age; obesity prevalence has increased as well as the number of hours that TV networks dedicate to children; during the last 30 y, the rate of children watching television for more than 4 h per day seems to have increased; children are exposed to a large number of important unhealthy stimulations in terms of food intake when watching television; over the last few years, the number of television food commercials targeting children have increased especially when it comes to junk food in all of its forms; the present use of food in movies, shows and cartoons may lead to a misconception of the notion of healthy nutrition and stimulate an excessive intake of poor nutritional food; and obese subjects shown in television programmes are in a much lower percentage than in real life and are depicted as being unattractive, unsuccessful and ridiculous or with other negative traits and this is likely to result in a worsening of the isolation in which obese subjects are often forced. The different European countries have different TV legislations.

CONCLUSION

The usual depiction of food and obesity in television has many documented negative consequences on food habits and patterns. The different national regulations on programs and advertising directed to children could have a role in the different prevalence of childhood obesity in different European countries. Television could be a convenient tool to spread correct information on good nutrition and obesity prevention.

Regular participation in sports is associated with enhanced physical fitness and lower fat mass in prepubertal boys

OBJECTIVE

To study the effect of physical activity on whole body fat (BF), its regional deposition and the influence of body fatness on physical performance in prepubertal children.

DESIGN

Cross-sectional study.

SUBJECTS

A total of 114 boys (9.4+/-1.5 y, Tanner I-II), randomly sampled from the population of Gran Canaria (Spain), 63 of them physically active (PA, at least 3 h per week during the previous year) and 51 nonphysically active (non-PA).

MEASUREMENTS

Body composition (DXA), anthropometric variables (body circumferences and skinfolds) and physical fitness were determined in all subjects.

RESULTS

The PA obtained better results in maximal oxygen uptake, isometric leg extension force, vertical jump (muscular power), and 300 m (anaerobic capacity) and 30 m running tests (speed) than the non-PA. A lower percentage of body fat (% BF) (4 U less, P<0.05), whole BF mass (36% less, P<0.05) and regional fat mass (28, 25, and 30% less in the trunk, legs and arms, respectively, all P<0.05) was observed in the PA compared to the non-PA. The waist and hip circumferences correlated more closely with both the fat mass accumulated in the trunk region and the % BF (r=0.81-0.95, P<0.001) than the waist-to-hip ratio (WHR). The WHR correlated with the percentage of the whole fat mass accumulated in the trunk (PFT) (r=0.52-0.53, P<0.001). In both groups, the PFT increased curvilinearly with the % BF, regardless of the level of physical activity. ANCOVA analysis revealed that total and regional fat masses explained less than 40% of the difference in performance between the PA and non-PA group. The mean speed in the 30 m running test (V30), combined with the height and whole body mass, has predictive value for the BF mass (R=0.98, P<0.001). The % BF may be estimated from the body mass index (BMI) and V30 (% BF=8.09+2.44.BMI (kg m(-2))-5.8.V30 (m s(-1)), R=0.94, P<0.001) in prepubertal boys.

CONCLUSIONS

Regular participation in at least 3 h per week of sports activities and competitions on top of the compulsory physical education program is associated with increased physical fitness, lower whole body and trunkal fat mass in prepubertal boys.

The relationship between socio-economic status and physical activity patterns in South African children

AIM

To examine: (1) the associations between socio-economic status, physical activity, anthropometric and body composition variables in South African children; (2) the influence maternal characteristics have on children's physical activity levels; and (3) associations between television watching, activity level and body composition.

METHODS

In 381 South African children, physical activity and socio-economic status were assessed via structured retrospective interview using validated questionnaires. An asset indicator score was calculated as a proxy measure of socio-economic status and used to divide children into quartiles.

RESULTS

Children falling into the highest socio-economic status quartile had mothers with the highest educational levels, generally came from dual parent homes, were highly physically active, watched less television, weighed more and had greater lean tissue than children in lower quartiles. A greater percentage of children living in dual parent homes and with mothers of a higher educational status were highly active compared with children living in single parent homes and with mothers of a lower educational status. We found greater levels of lean mass with increased activity level after controlling for television watching time and fat mass. There were high levels of low activity and high television watching time among lower socio-economic status groups. There were significant racial differences in patterns of activity. White children were found to be more active than black children, more likely to participate in physical education classes at school and watched less television than black children.

CONCLUSION

Physical activity levels and socio-economic variables are closely related in this population of South African children.

The nutrition transition in Spain: a European Mediterranean country

BACKGROUND

Mediterranean diets are felt to be healthful diets linked with reduced mortality from diet-related noncommunicable diseases.

OBJECTIVE

To examine trends in diet, activity, obesity and diet-related noncommunicable diseases for Spain and compare these with other European countries, particularly those from the Mediterranean area.

DESIGN

A combination of large-scale primary and secondary nationally representative data analysis are used.

DATA

Nationally representative data on household food consumption, physical activity, adult obesity, and cause of death are combined with regionally representative adolescent obesity data, obtained in the last four decades. Comparative diet and obesity data come from nationally representative comparable data, obtained during the same period.

RESULTS

The Spanish diet has shifted toward a very high level of fat intake, high fruit and dairy intake and moderate vegetable intake. Dairy and fruit intakes were the highest in Europe, as was the proportion of energy from fat, when we compared with the available data. Adult overweight and obesity trends show a marked increase in the past decade to levels as high as Italy and far above France. Overweight for children aged 6-7 is above that of even the USA, while adolescent overweight levels are among the highest in the world. Cardiovascular disease mortality is low, as with Italy and France, and the cancer mortality rate is lower than Italy and France.

CONCLUSIONS

We have observed that, in Spain, relatively high obesity prevalences and dairy intake levels are related to much lower levels of cardiovascular disease and cancer mortality than are found in other European countries. This unique Spanish dietary and obesity pattern should be further explored in order to clarify the causal links.

SUPPORT

The National Institutes of Health (NIH; R01-HD30880 and R01-HD38700).

Secular increases in body fat percentage in male children of Zaragoza, Spain, 1980-1995

BACKGROUND

Data on temporal changes on total body fat percentage (TBF%) are scarce, and no such data are known to exist in Spain. The aim of our study was to describe secular increases in TBF% in male children and adolescents of Zaragoza, Spain, from 1980 to 1995.

METHODS

The samples analyzed in the present study have been included in two cross-sectional surveys conducted in 1980 and 1995. The samples selected for the 1980 and 1995 surveys comprised 1553 and 701 male children with ages ranging from 6.0 to 14.9 years. Weight, height, and four skinfold thicknesses were measured. From these measurements we have calculated TBF%.

RESULTS

Concerning body mass index (BMI), we have observed significant increases from 8.5 to 11.5 years, ranging in this age group from 0.80 to 1.45 kg/m(2). TBF% showed significant increases at all age groups, with percentage increases of 2.46% at 13.5 years and 6.03% at 11.5 years.

CONCLUSIONS

We have shown a secular increase in TBF% in children aged 6.0 to 15.0 years that is greater than the increase in BMI. The similarity of our findings for both relative weight and skinfold thickness, even with less significant differences for BMI, suggests that, in children of Zaragoza, Spain, adiposity has increased during the 1980-1995 period.

Secular changes in body fat patterning in children and adolescents of Zaragoza (Spain), 1980-1995

OBJECTIVE

To examine whether children and adolescents of Zaragoza (Spain) are becoming centrally obese to a greater extent than would be predicted by their relative body weights.

DESIGN

Two cross-sectional surveys conducted in 1980 and 1995.

SUBJECTS

The samples selected for the 1980 and 1995 surveys comprised 1553 and 701 male children, and 1311 and 659 female children, respectively, with ages ranging from 6.0 to 14.9 y.

MEASUREMENTS

We measured four skinfold thicknesses (biceps, triceps, subscapular, suprailiac) and calculated some indices of fat patterning: triceps/subscapular skinfolds (T/SS), biceps+triceps/subscapular+suprailiac skinfolds (B+T/SS+SI), and (subscapular+suprailiac/biceps+triceps+subscapular+suprailiac skinfolds)x100 (trunk-to-total skinfolds %).

RESULTS

In males, B+T/SS+SI, and trunk-to-total skinfolds % showed a significant trend to a central pattern of fat distribution from 1980 to 1995, at the ages of 6.5-11.5 y. In females, B+T/SS+SI and trunk-to-total skinfolds % showed a significant trend to a central pattern of fat distribution from 1980 to 1995, at the ages of 6.5 and 7.5 y. Similar results were obtained when we adjusted for BMI values.

CONCLUSION

We have observed a trend to a central pattern of adipose tissue distribution, especially in males and at the youngest ages studied (6-11 y in males, and 6-7 y in females). These observations were independent of trends in BMI.

Sociodemographic factors and trends on overweight prevalence in children and adolescents in Aragón (Spain) from 1985 to 1995

From 1985 to 1995, the Aragón School Health Examination Surveys staff has surveyed the whole population of children (age 6-7 years) and adolescents (age 13-14 years). A total of 90,997 children (age 6-7 years) were examined in the nine cross-sectional surveys conducted between 1985 and 1995. A total of 106,284 adolescents (age 13-14 years) were also examined. We defined overweight when the body mass index was > or = 95th percentile. The measure of association between overweight and the other variables studied was the odds ratio, which was calculated by logistic regression. In the children and adolescents studied, the probability to be overweight was higher in the rural than in the urban areas. In the adolescents, the probability to be overweight was higher in the public than in the private schools. Our results also show a significant increase in the prevalence of overweight children in the region of Aragón (Spain) during the 1985-1995 decade, especially in males. Prevention of overweight in the populations at risk would help reduce social inequality in health, a major challenge for public health policy.

Trends in body mass index and overweight prevalence among children and adolescents in the region of Aragón (Spain) from 1985 to 1995

OBJECTIVE

To analyse trends in body mass index (BMI) and overweight prevalence for children and adolescents in the region of Aragón (Spain), from 1985 to 1995.

DESIGN

Nine cross-sectional examinations of schoolchildren conducted yearly from 1985 to 1995.

SUBJECTS

A total of 90,997 children (45,970 males and 45,027 females) in the first school year (6-7 y of age); 106,284 scholars (52,772 males and 53,512 females) in the last school year (13-14 y of age).

MEASUREMENTS

Heights and weights were measured and BMI (kg/m2) was calculated.

RESULTS

We observed a trend to higher BMI values across the surveys, by sex and age. The secular trends in BMI showed the largest increases at the upper ends of the distribution, especially in males. In children in the first school year, prevalences of overweight were higher in females than in males (P<0. 001); however, in adolescents in the last school year, prevalences were higher in males than in females (P<0.001). We observed a significant trend in overweight prevalence from 1985 to 1995 in children from the first school year (P=0.0183, in males and P=0.0168, in females). In children in the last school year there was only a significant trend in males (P<0.0001).

CONCLUSION

Significant changes in BMI occurred in the population studied during the period 1985-1995, but these changes differ by age and sex. The increasing skewness of BMI in the upper percentiles of the population, especially in boys, suggests that, not only is the pediatric population getting fatter, but the fatter members are becoming more obese. Our results also show a striking increase in the prevalence of overweight children in the region of Aragón (Spain) during the 1985-1995 decade.