***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Television viewing is associated with childhood obesity . Eating during viewing and eating highly advertised foods are 2 of the hypothesized mechanisms through which television is thought to affect children 's weight . OBJECTIVES Our objectives were to describe the amounts and types of foods that children consume while watching television  , compare those types with the types consumed at other times of the day , and examine the associations between children 's body mass index ( BMI )  and the amounts and types of foods consumed during television viewing . DESIGN Data were collected from 2 sample s. The first sample consisted of ethnically diverse third- grade children , and the second consisted predominantly of Latino fifth- grade children . Three nonconsecutive 24-h dietary recalls were collected from each child . For each eating episode reported , children were asked whether they had been watching television . Height and weight were measured by using st and ard methods and were used to calculate BMI . RESULTS On weekdays and weekend days , 17 - 18 % and approximately 26 % of total daily energy , respectively , were consumed during television viewing in the 2 sample s. Although the fat content of the foods consumed during television viewing did not differ significantly from that of the foods consumed with the television off , less soda , fast food , fruit , and vegetables were consumed with the television on . The amount of food consumed during television viewing was not associated with children 's BMI , but in the third- grade sample , the fat content of foods consumed during television viewing was associated with BMI . CONCLUSIONS A significant proportion of children 's daily energy intake is consumed during television viewing , and the consumption of high-fat foods on weekends may be associated with BMI in younger children OBJECTIVES This study examined the effects of pricing and promotion strategies on purchases of low-fat snacks from vending machines . METHODS  Low-fat snacks were added to 55 vending machines in a convenience sample of 12 secondary schools and 12 worksites . Four pricing levels ( equal price , 10 % reduction , 25 % reduction , 50 % reduction ) and 3 promotional conditions ( none , low-fat label , low-fat label plus promotional sign ) were crossed in a Latin square design . Sales of low-fat vending snacks were measured continuously for the 12-month intervention . RESULTS Price reductions of 10 % , 25 % , and 50 % on low-fat snacks were associated with significant increases in low-fat snack sales ; percentages of low-fat snack sales increased by 9 % , 39 % , and 93 % , respectively . Promotional signage was independently but weakly associated with increases in low-fat snack sales . Average profits per machine were not affected by the vending interventions . CONCLUSIONS Reducing relative prices on low-fat snacks was effective in promoting lower-fat snack purchases from vending machines in both adult and adolescent population The association of television viewing and obesity in data collected during cycles II and III of the National Health Examination Survey was examined . Cycle II examined 6,965 children aged 6 to 11 years and cycle III examined 6,671 children aged 12 to 17 years . Included in the cycle III sample were 2,153 subjects previously studied during cycle II . These surveys , therefore , provided two cross-sectional sample s and one prospect i ve sample . In all three sample s , significant associations of the time spent watching television and the prevalence of obesity were observed . In 12- to 17-year-old adolescents , the prevalence of obesity increased by 2 % for each additional hour of television viewed . The associations persisted when controlled for prior obesity , region , season , population density , race , socioeconomic class , and a variety of other family variables . The consistency , temporal sequence , strength , and specificity of the associations suggest that television viewing may cause obesity in at least some children and adolescents . The potential effects of obesity on activity and the consumption of calorically dense foods are consistent with this hypothesis OBJECTIVES To test whether increased television viewing is associated with increased total energy intake and with increased consumption of foods commonly advertised on television , and to test whether increased consumption of these foods mediates the relationship between television viewing and total energy intake . DESIGN Prospect i ve observational study with baseline ( fall 1995 ) and follow-up ( spring 1997 ) measures of youth diet , physical activity , and television viewing . We used food advertising data to identify 6 food groups for study ( sweet baked snacks , c and y , fried potatoes , main courses commonly served as fast food , salty snacks , and sugar-sweetened beverages ) . SETTING AND PARTICIPANTS Five public schools in 4 communities near Boston . The sample included 548 students ( mean age at baseline , 11.70 years ; 48.4 % female ; and 63.5 % white ) . MAIN OUTCOME MEASURES Change in total energy intake and intake of foods commonly advertised on television  from baseline to follow-up . RESULTS After adjusting for baseline covariates , each hour increase in television viewing was associated with an additional 167 kcal/d ( 95 % confidence interval , 136 - 198 kcal/d ; P<.001 ) and with increases in the consumption of foods commonly advertised on television . Including changes in intakes of these foods in regression models provided evidence of their mediating role , diminishing or rendering nonsignificant the associations between change in television viewing and change in total energy intake . CONCLUSIONS Increases in television viewing are associated with increased calorie intake among youth . This association is mediated by increasing consumption of calorie-dense low-nutrient foods frequently advertised on television 
    Output:
    
Food promotions have a direct effect on children 's nutrition knowledge , preferences , purchase behaviour , consumption patterns and diet-related health .
Current marketing practice predominantly promotes low nutrition foods and beverages .
Rebalancing the food marketing l and scape ' is a recurring policy aim of interventions aim ed at constraining food and beverage promotions to children .
The collective review evidence on marketing practice indicates little progress towards policy aims has been achieved during the period 2003 - 2012 .
There is a gap in the evidence base on how substantive policy implementation can be achieved .