Limiting food advertising on TV: estimating the impact on obesity in children Lennert Veerman Ed van Beeck Johan Mackenbach

2/16 Overview  Introduction  Analytical framework  Baseline situation  Exposure -> consumption  Consumption -> mean weight & BMI  BMI -> prevalence overweight  Limitations and sensitivity  Uncertainty in policy  Conclusions

3/16 Introduction  Project on methods for (forecasting in) HIA  Overweight in children increasing  ‘Covenant Overweight’  Discussion on role of TV and food advertising

4/16 Study question  What effects on overweight and obesity prevalence among 6 to 12-year old children can be expected of restrictions on food advertising on TV?

5/16 Analytical framework Intervention or policy Exposure to food commercials Change in mean BMI Literature, experts, argument Simulation model Change prevalence overweight & obesity Simulation model

6/16 Prevalence overweight Age BoysOverweight (incl. obesity) 14.8% obesity3.2% GirlsOverweight (incl. obesity) 19.4% obesity4.1%

7/16 Baseline assessment - BMI distribution

8/16 From exposure to consumption  Baseline exposure in NL:  12 minutes of food advertising per week.  Measure of effect needed - by how much does the body weight change per minute exposure per week?  Only one good quality study gives dose-effect estimate: 1.39% extra kcal per 25 minutes exposure.  Dutch situation: at zero exposure 0.65% less kcal.  Boys 13 kcal/day, girls 12 kcal/day on average.

9/16 From consumption to weight and BMI  Heavy people need to eat more: kcal/day/kg of extra body weight.  Effect of eating kcal less: 0.6 kg body weight, or 0.4 kg/m 2.

10/16 From mean BMI to prevalence of overweight

11/16 Prevalence overweight

12/16 Results  Reducing exposure of 6-12 year olds to televised food commercials could reduce the prevalence of overweight by almost 4 %-pt and reduce the prevalence of obesity by 1 to 1.5 %-pt.

13/16 Limitations & sensitivity  Parameter uncertainty:  Effect measure Bolton  - data from US 1977  - possibly some snacking-while-watching included  Sensitivity (50%, 200%) for effect on overweight M+F: -3.8 (-1.9, -7.4) %-pt  Link kcal-weight based on adults  effect for 25 and 15 kcal/kg: -3.0, -5.0 %-pt  Model uncertainty:  - no time dimension

14/16 Discussion  Step from overweight prevalence to disease and (healthy) life expectancy could be added  Limiting exposure to food advertising is likely to reduce inequalities

15/16 Uncertainty around effects of policy  Effect of legal measures undercut by  - broadcasting from abroad  - different marketing channels (internet, direct)  Voluntary restrictions by business

16/16 Conclusions  Exposure of children to commercials for (energy dense) food increases their body mass. Current estimate indicates a substantial effect.  Governments, EU and other parties should strive to minimise this exposure in the interest of the (future) health of children.  A monitoring system of both exposure to food advertising and overweight prevalence should be put in place.  Further research could focus on estimating the dose-response relationship, on marketing practices and on policy options for (health) authorities.

17/16 Prevalence overweight Age 6-12 Current (2003) No TV food ads 1980 Boys Overweight (incl. obesity) 14.8%11.1%3.6% obesity3.2%1.9%0.1% Girls Overweight (incl. obesity) 19.4%15.4%6.9% obesity4.1%2.6%0.5%