A Prosocial Purpose for Healthy Eating Makes Health an ...
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A Prosocial Purpose for Healthy Eating Makes Health an Appealing Identity and Doubles the Free-Choice Selection of Healthy Options in a Double-Blind Field Experiment Cintia P. Hinojosa 1 , Christopher J. Bryan 2 , Mari Kawamura 2 , Fred Steubing 3 , & David S. Yeager 1 1 Department of Psychology, The University of Texas at Austin, 2 Department of Psychology, The University of California at San Diego, 3 Comal Independent School District, Texas. 13% 10% 27% 0% 5% 10% 15% 20% 25% 30% Percentage Freely Choosing a Healthy Snack + Water No-treatment classes (non- randomized control, n = 30) Standard health education message (randomized control, n = 88) Prosocial purpose for healthy eating (randomized treatment, n = 83) Background • Rising obesity rates pose a great threat to public health and the national economy 8 • Prevention is better than treatment, but no existing preventative interventions have a lasting impact on teens’ free choices of healthy foods 7 • Traditional health programs assume that self-interest – i.e., “being healthy”—is a motivating factor for teens • But adolescents have an interest in “mattering” and impacting the world beyond the self—i.e., having a prosocial purpose—and they desire autonomy and dislike authorities impinging on personal choices 6, 9 Objectives • Develop a novel health program that focuses on three developmentally appropriate values: 1) Beyond-the-self purpose and social justice 2) Autonomy and resistance of authority 3) Development of a positive self-identity • Include manipulations of social norms and “self- persuasion” strategies 3 in the novel program to create a lasting effect 1 • Evaluate the effectiveness of the novel program on 1) Values directly targeted: prosocial purpose, autonomy, and healthy eater identity 2) Free-choice eating behavior one day post- intervention, in a blinded choice paradigm Participants • 201 13 and 14 y/o 8 th grade students in 15 classes at a Texas middle school Conditions (individual-level random assignment) • No treatment (Non-randomized control) • Standard practice health education program (Randomized control) • Prosocial purpose for healthy eating program (Randomized treatment) Procedures Day 1 - 50 minute classroom session; students receive unmarked envelopes with different conditions • Individually read either control or prosocial purpose health article (see Figs. 1 and 2) • Read normative quotes from parents and teachers (control) or from 9 th grade peers (treatment) • Write two essays as “self-persuasion” exercises 1) Summarize new and interesting information 2) Describe possible healthy behaviors • Complete identity, autonomy, and prosocial purpose questionnaire (see Fig. 3) Day 2 - 5 minute DV (from principal, double-blind) • Select snack and drink options from a menu framed as part of an unrelated class-wide reward Prosocial Purpose “When I choose healthy food instead of unhealthy food, I'm standing up for people in need” (Scale: 1-5) Randomized treatment group (M=3.18, SD=0.11) higher than randomized control (M=2.30, SD=0.82), t(200) = -6.44, p=.000, d=-0.88 Autonomy “Eating healthy is a way to stand up to people who are trying to control us” (Scale: 1-5) Randomized treatment group (M=1.97, SD=0.85), higher than control (M=1.25, SD=0.66), t(200) = -6.80, p=.000, d=-0.93 Healthy Eater Identity “I respect healthy eaters more than unhealthy eaters” Randomized treatment group (M=3.44, SD=0.95) higher than randomized control (M=2.99, SD=-.88), t(200) = -3.57, p=.000, d=0.49 • Single class-session reading and writing exercise increased valuing of healthy eating as a prosocial act, healthy eating as a way to reassert autonomy from food corporations, and thereby “healthy eater” as an appealing identity. • Treated participants chose more healthy options one day after the program in a blinded choice paradigm. • Standard program participants were no different from no-treatment controls, ruling out demand effects. • Future study: include noun-verb manipulation to strengthen the identity behavior link 2 1. Aronson, E. (1999). The power of self-persuasion. American Psychologist, 54, 875–884. 2. Bryan, C. J., Walton, G. M., Rogers, T., & Dweck, C. S. (2011). Motivating voter turnout by invoking the self. Proceedings of the National Academy of Sciences, USA, 108, 12653-12656. 3. Cialdini, R. B. (2003). Crafting normative messages to protect the environment. Current Directions in Psychological Science, 12, 105-109. 4. Damon, W., Menon, J., & Bronk, K. C. (2003). The development of purpose during adolescence. Applied Developmental Science, 7, 119-128. 5. Hicks, R. & Tingley, D. (2011) mediation: Stata package for causal mediation analysis. 6. Imai, K., L. Keele, & D. Tingley. 2010. A general approach to causal mediation analysis. Psychological Methods 15: 309-334. 7. Mendoza, M. (2007, July 7). Nutrition education ineffective. USA Today, pp.1-4. 8. Wang, Y., McPherson, K., Marsh, T., Gortmaker, S. L., Brown, M. (2011). Health and economic burden of the projected obesity trends in the US and the UK. Lancet, 378, 815–825. 9. Yeager, D.S., & Bundick, M.J. (2009). The role of purposeful work goals in promoting meaning in life and in school- work during adolescence. Journal of Adolescent Research, 24, 423–452. Special thanks to the New Paths to Purpose Project at the University of Chicago Booth School of Business for funding the present study. We would also like to extend our thanks and appreciation to the faculty and staff of the partnering school district who helped in the execution of the study. Additional thanks to Peter Fisher of the University of California at San Diego and to all of the members of the Adolescent Development Research Group at the University of Texas for their help in the preparation of the study and of the data. Purpose for Healthy Eating Randomized Treatment Prosocial and Autonomous Construal of Healthy Eating (Composite) Appeal of Healthy Eater Identity Actual Free-Choice Healthy Food Selections One Day Post-Intervention Fig 5. Path model. All variables z-scored. Indirect effect from randomized treatment to identity through autonomy/purpose was significant, β = .27 [.17, .37], as was effect from treatment to behavior through identity, unst. b = .02 [.0009, .04]. Fig 1. Excerpts from standard practice health article and normative quotes (control) Fig 4. Food menu used as behavioral DV Fig 2. Excerpts from prosocial purpose health article and normative quotes (treatment) Fig 3. Excerpt from questionnaire β=.43*** β=.63*** β=.26*** β=-0.02 OR=1.71** OR=1.45+ OR=1.64* Overall χ 2 (2) = 8.28, p = .016
Transcript of A Prosocial Purpose for Healthy Eating Makes Health an ...
A Prosocial Purpose for Healthy Eating Makes Health an Appealing Identity and Doubles the Free-Choice Selection of Healthy Options in a Double-Blind Field Experiment
Cintia P. Hinojosa1, Christopher J. Bryan2, Mari Kawamura2, Fred Steubing3, & David S. Yeager1 1Department of Psychology, The University of Texas at Austin, 2Department of Psychology, The University of California at San Diego, 3Comal Independent School District, Texas.
13% 10% 27% 0%
5%
10%
15%
20%
25%
30%
Perc
enta
ge F
reel
y C
hoos
ing
a H
ealth
y Sn
ack
+ W
ater
No-treatment classes (non-randomized control, n = 30)
Standard health education message (randomized control, n = 88)
Prosocial purpose for healthy eating (randomized treatment, n = 83)
Background • Rising obesity rates pose a great threat to public health
and the national economy8
• Prevention is better than treatment, but no existing preventative interventions have a lasting impact on teens’ free choices of healthy foods7
• Traditional health programs assume that self-interest –i.e., “being healthy”—is a motivating factor for teens
• But adolescents have an interest in “mattering” and impacting the world beyond the self—i.e., having a prosocial purpose—and they desire autonomy and dislike authorities impinging on personal choices6, 9
Objectives • Develop a novel health program that focuses on three
developmentally appropriate values: 1) Beyond-the-self purpose and social justice 2) Autonomy and resistance of authority 3) Development of a positive self-identity
• Include manipulations of social norms and “self-persuasion” strategies3 in the novel program to create a lasting effect1
• Evaluate the effectiveness of the novel program on 1) Values directly targeted: prosocial purpose,
autonomy, and healthy eater identity 2) Free-choice eating behavior one day post-
intervention, in a blinded choice paradigm
Participants • 201 13 and 14 y/o 8th grade students in 15 classes at a
Texas middle school
Conditions (individual-level random assignment) • No treatment (Non-randomized control) • Standard practice health education program
(Randomized control) • Prosocial purpose for healthy eating program
(Randomized treatment)
Procedures Day 1 - 50 minute classroom session; students receive unmarked envelopes with different conditions
• Individually read either control or prosocial purpose health article (see Figs. 1 and 2)
• Read normative quotes from parents and teachers (control) or from 9th grade peers (treatment)
• Write two essays as “self-persuasion” exercises 1) Summarize new and interesting information 2) Describe possible healthy behaviors
• Complete identity, autonomy, and prosocial purpose questionnaire (see Fig. 3)
Day 2 - 5 minute DV (from principal, double-blind) • Select snack and drink options from a menu framed
as part of an unrelated class-wide reward
Prosocial Purpose “When I choose healthy food instead of unhealthy food, I'm standing up for people in need” (Scale: 1-5) Randomized treatment group (M=3.18, SD=0.11) higher than randomized control (M=2.30, SD=0.82), t(200) = -6.44, p=.000, d=-0.88
Autonomy “Eating healthy is a way to stand up to people who are trying to control us” (Scale: 1-5) Randomized treatment group (M=1.97, SD=0.85), higher than control (M=1.25, SD=0.66), t(200) = -6.80, p=.000, d=-0.93
Healthy Eater Identity “I respect healthy eaters more than unhealthy eaters” Randomized treatment group (M=3.44, SD=0.95) higher than randomized control (M=2.99, SD=-.88), t(200) = -3.57, p=.000, d=0.49
• Single class-session reading and writing exercise increased valuing of healthy eating as a prosocial act, healthy eating as a way to reassert autonomy from food corporations, and thereby “healthy eater” as an appealing identity.
• Treated participants chose more healthy options one day after the program in a blinded choice paradigm.
• Standard program participants were no different from no-treatment controls, ruling out demand effects.
• Future study: include noun-verb manipulation to strengthen the identityà behavior link2
1. Aronson, E. (1999). The power of self-persuasion. American Psychologist, 54, 875–884. 2. Bryan, C. J., Walton, G. M., Rogers, T., & Dweck, C. S. (2011). Motivating voter turnout
by invoking the self. Proceedings of the National Academy of Sciences, USA, 108, 12653-12656.
3. Cialdini, R. B. (2003). Crafting normative messages to protect the environment. Current Directions in Psychological Science, 12, 105-109.
4. Damon, W., Menon, J., & Bronk, K. C. (2003). The development of purpose during adolescence. Applied Developmental Science, 7, 119-128.
5. Hicks, R. & Tingley, D. (2011) mediation: Stata package for causal mediation analysis. 6. Imai, K., L. Keele, & D. Tingley. 2010. A general approach to causal mediation
analysis. Psychological Methods 15: 309-334. 7. Mendoza, M. (2007, July 7). Nutrition education ineffective. USA Today, pp.1-4. 8. Wang, Y., McPherson, K., Marsh, T., Gortmaker, S. L., Brown, M. (2011). Health and
economic burden of the projected obesity trends in the US and the UK. Lancet, 378, 815–825.
9. Yeager, D.S., & Bundick, M.J. (2009). The role of purposeful work goals in promoting meaning in life and in school- work during adolescence. Journal of Adolescent Research, 24, 423–452.
Special thanks to the New Paths to Purpose Project at the University of Chicago Booth School of Business for funding the present study. We would also like to extend our thanks and appreciation to the faculty and staff of the partnering school district who helped in the execution of the study. Additional thanks to Peter Fisher of the University of California at San Diego and to all of the members of the Adolescent Development Research Group at the University of Texas for their help in the preparation of the study and of the data.
Purpose for Healthy Eating Randomized
Treatment
Prosocial and Autonomous Construal
of Healthy Eating (Composite)
Appeal of Healthy Eater
Identity
Actual Free-Choice Healthy Food
Selections One Day
Post-Intervention
Fig 5. Path model. All variables z-scored. Indirect effect from randomized treatment to identity through autonomy/purpose was significant, β = .27 [.17, .37], as was effect from treatment to behavior through identity, unst. b = .02 [.0009, .04].
Fig 1. Excerpts from standard practice health article and normative quotes (control)
Fig 4. Food menu used as behavioral DV Fig 2. Excerpts from prosocial purpose health article and normative quotes (treatment)
Fig 3. Excerpt from questionnaire
β=.43***
β=.63***
β=.26***
β=-0.02 OR=1.71**
OR=1.45+
OR=1.64*
Overall χ2(2) = 8.28, p = .016
