A field study looked at whether advertising shaped the food choices of university students with ADHD. It took place in one faculty cafeteria at Hebrew University of Jerusalem. The food analyses used 427 students who bought a meal, 193 with ADHD and 234 without. Students with ADHD reported being recognized by the university after a formal assessment.
Over 24 days, eight had no advertising. On eight more, a healthy egg and vegetable sandwich was advertised at eye level. On the rest, a high-fat cream-cheese sandwich got the same treatment.
With no advertising, students with ADHD chose healthy items far less often than other students, a gap unlikely to be down to chance (19 of 71 versus 64 of 85). Students with ADHD bought more of whichever sandwich was advertised, but the other students' choices did not change. During healthy advertising, the two groups no longer clearly differed (62% versus 70% choosing healthy items). During unhealthy advertising, the gap stayed (27% versus 71%). Allowing for the 54 students who used ADHD medication did not change the results much.
The authors note that the sample came from one faculty and the ADHD group was high functioning. Advertising and eye-level placement were combined, so it is unclear which one mattered. The abstract's total of 457 also does not match the body.
The authors suggest that highlighting healthy foods, such as advertising a healthy option at eye level, may help students with ADHD choose healthier food.
The numbers Stats and what the terms mean
The statistics behind the plain-language claims above.
- Hershko, 2019: healthy choices by students with and without ADHD with no advertising, chi2(1) = 36.60, p < .001.
- Hershko, 2019: purchases of the advertised egg sandwich among students with ADHD, chi2(1) = 4.50, p < .05.
- Hershko, 2019: purchases of the advertised cheese sandwich among students with ADHD, chi2(1) = 9.81, p < .01.
- Hershko, 2019: healthy choices by the two groups during healthy advertising, chi2(1) = .98, p = .36.
- Hershko, 2019: healthy choices by the two groups during unhealthy advertising, chi2(1) = 25.76, p < .001. What the terms mean:
- chi2 A test of whether two groups differ in how often they make a choice; a bigger value means a bigger difference.
- p How likely a difference this large would be if chance alone were at work; below .05 is usually taken as unlikely to be chance.
Source: Hershko S, Cortese S, Ert E, et al.. Advertising Influences Food Choices of University Students With ADHD. Journal of Attention Disorders (2019). doi:10.1177/1087054719886353