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Tackling childhood obesity: examining the causes and best preventive measures

Published: 8 Oct 2014

Guest Author: Professor Glen Wiggs

Director, Foundation for Advertising Research
Adjunct Professor of Advertising Regulation University of the Sunshine Coast, Queensland

Childhood obesity and its consequential health problems make it a serious ongoing concern. Advertising, lack of physical activity and diets with high intake of fast food are the target culprits as the contributing factors. Now two recent US studies that are examined in this article have considered the impact of these relative variables and the deterrent effectiveness of different preventive measures.

 

The first US study focusing specifically on fast food restaurants. It analysed the sources of energy, sodium, sugar and solid fat consumed by children and adolescents 4-19 from grocery stores, quick service restaurants, full service restaurants and school cafeterias.

The second US study examined the effectiveness of three interventions: Afterschool physical activity, a 1-cent per ounce excise tax on sugared drinks and a ban on fast food TV advertising targeting children.

 

1. Study into the impact of fast food

The study ‘A New Method to Monitor the Contribution of Fast Food Restaurants to the Diets of US Children’ by Colin Rehm and Adam Drewnowski of the University of Washington was published in PLOS One which is an Open Access publication of the Public Library of Science.

The study looked at rates of consumption of energy, sodium, added sugars and solid fast by US children and adolescents aged between 4 to 19 years old for foods consumed away from home. This included grocery stores, quick service/fast food restaurants, full service restaurants and school cafeterias.

The purpose of the study was to look beyond the nutritional content of products available at different locations and consider the actual impact each had on the diet of children and adolescents.

The study was conducting by looking at data from the US National Health and Nutrition Examination Study (NHANES). Children reported all food and beverages consumed in a 24 hour period, including the name, time and place of consumption. This was then assessed to determine intakes of added sugars and solid fats (etc). 

The authors found that children and youth aged 4-19 derived their energy from the following sources:
- Grocery stores - 64.8%
- Fast food restaurants - 14.1%
- Full service restaurants – 5.6%
- School cafeterias – 7.2%
- Other – 8.2%

Overall, fast food restaurants (Quick Service Restaurants or ‘QSR’) were found to be the second highest source of dietary energy, sodium, added sugars and solid fats, behind products from supermarkets are grocery stores.

The study compared eight different sectors of fast food restaurants – Burger (eg McDonald’s), Pizza (eg Domino’s), Sandwich (eg Subway), Chicken (eg KFC), Mexican (eg Taco Bell), Asian (eg Panda Express), Fish (eg Long John Silver’s) and Coffee/Snacks (eg Starbucks).

Findings showed that:

  • 35.7% of all children consumed fast food items on a given day 
    • 17% consumed items from burger restaurants 
    • 9% from pizza restaurants 
    • 4% from sandwich, chicken and Mexican FFRs 
  • Burger restaurants provided the most energy (6.2% overall), pizza second most (3.3% overall)

The analysis of the amount of sodium, added sugar and solid fats consumed showed inconclusive results as highlighted in the table below. If the views of health advocates were to be believed, then food sourced from grocery stores would have lower percentages of sodium, sugar and fat than the energy figure. Conversely for fast food restaurants they would be higher.

Measurement of Whether the Proportions of Sodium, Added Sugar and Total Fat are Higher or Lower than the Proportion of Energy 

Source                                               Sodium                  Sugar                      Fat
Grocery Stores                                     Lower                     Higher                      Lower
Fast Food Restaurants                          Higher                    Lower                       Higher
Full Service Restaurants                        Higher                    Lower                       Higher
School Cafeterias                                  Higher                    Lower                       Higher
Other                                                   Lower                      Higher                      Lower
 
This study is useful in that it demonstrates that the nutritional value of food sold by grocery stores, school cafeterias or full service restaurants is no better or worse than that that sold by QSR outlets.

It can be argued that QSR outlets are being discriminated against in some jurisdictions with proposals to restrict the number and position of QSR outlets. This discrimination is based on the assumption that the food sold by QSR outlets is inherently unhealthy and that supermarkets and other stores are a better source of healthy food. Thus grocery stores are encouraged and QSR outlets discouraged by the use of zoning and other regulatory measures.


2. Study into preventive measures

Released in the American Journal of Preventive Medicine, the study “Reducing Childhood Obesity Through US Federal Policy” examined the literature regarding the following three interventions: 

  • Afterschool physical activity
  • A 1-cent per ounce excise tax on sugared drinks
  • A ban on fast food TV advertising targeting children 

Using two demographics – children 6-12 years and adolescents 13-18 years, a simulation model was created to estimate the impact of each intervention over time and in particular by 2032. 

For children 6-12, an afterschool activity program appeared to be the most effective intervention. It was estimated that the rate of obesity would reduce by 1.8% by 2032 and a 1-cent per ounce soda tax would achieve a reduction of 1.6%. The ban on advertising fast food to children on TV would reduce obesity by only 0.9%. 

For adolescents 13-18, the results were slightly different.  The most effective intervention would be a soda tax with an estimated 2.4% reduction in obesity. The afterschool activity program would reduce obesity by 1.9% and the TV ad ban is estimated to reduce obesity by only 0.8%.

In trying to account for the poor performance of an ad ban the authors say –

The child-directed ban on fast food TV advertising has the greatest predicted behavioral impact, but would reduce obesity prevalence the least. This is due to the substitution effect and the policy’s narrow focus on fast food. 

Not too much reliance can be placed on the value of the study as it is an attempt to foretell the future using a simulation model that predicts results in 18 years time. However, the outcome of the study showed the ineffectiveness of ad bans. This must be quite a disappointment for the health lobby that advocates ad bans as a solution to the obesity problem.

 

Conclusions

The growing identification of childhood obesity, its causes and potential remedies highlight the need for action. Interestingly, the first study raises doubt about the truth in public expectation about the quality of food consumed by children which is purchased in different retail environments such as supermarkets and fast food restaurants. Although the second study appears predominantly to be speculation, it does highlight a range of possible ways to address the problem of childhood obesity and prompts us to re-examine our desire to blame advertising for poor health choices. How governments and industry address this issue is however still under speculation.