PEER INFLUENCES ON WEIGHT GAIN: A NEW LOOK AT THE … · 2014. 10. 21. · predicted weight gain in college students (Levitsky et al. 2004) Jhon Wlaschin • Peer Socialization HYPOTHESES

Jhon Wlaschin • Peer Socialization

PEER INFLUENCES ON WEIGHT GAIN: A NEW LOOK AT THE FRESHMAN 15

Jhon Wlaschin February 16, 2011


HOW DO FRIENDS INFLUENCE EACH OTHER?

•  Social norms have a powerful affect on behavior

•  First impressions matter a great deal

•  People adjust their behavior to align with the values of their friends


YOUR FRESHMAN YEAR



PROBABILITY OF BECOMING OBESE ACCORDING TO RELATIONSHIP TYPE

Christakis NA, Fowler JH. N Engl J Med 2007;357:370-379

0 20 40 60 80

100 120 140 160 180

Close friend Oposite sex friend

spouse sibling

"Increase in Risk of Obesity %"


WHAT’S SHE LIKE?


DO WE VALUE THE SAME THINGS?

•  Social Norms


SOCIAL NORMS HAVE A POWERFUL AFFECT ON BEHAVIOR

•  Why do people adhere to social norms?

•  Source of information as to how to behave appropriately

•  Adherence to norms serves as a self-presentation strategy

•  People believe that adhering to norms will lead others to like and accept them


WHAT DO ROOMMATES CARE ABOUT?

•  Two students who don’t know each other begin to share a room.

•  Want to get along

•  Enjoy doing things together

•  Avoid conflict

•  How?


MODELING AND MIMICRY

•  Similarity promotes attraction and the development of interpersonal relationships (Berscheid & Walster, 1983)

•  Individuals who mimic the behavior of others tend to be liked more than those who do not mimic (Chartrand & Bargh, 1999).


SOCIALIZATION

•  Socialization is a process of learning that occurs through imitation, identification and internalization of the behaviors and attitudes of others. (Hartup, 1999)

•  Interpersonal experiences create expectations that inform future relationships (Bowlby, 1969)


SIMILARITY THROUGH SOCIALIZATION OF RISKY HEALTH BEHAVIORS

•  Marijuana Use (Kandel, 1978)

•  Binge drinking and sexual behavior (Jaccard, Blanton, & Dodge, 2005)

•  Binge eating (Crandall, 1988)


NORMATIVE SOCIAL INFLUENCE OF EATING

•  People tend to observe the eating behavior of others to establish maximum levels of intake that is socially acceptable. (Herman, Roth & Polivy, 2003)

•  Participants consistently will eat more when confederates eat large amounts and will eat less when confederates eat minimally (Nisbett & Storms, 1974; Roth, Herman, Polivy, & Pliner, 2001)


FIRST IMPRESSIONS MATTER A GREAT DEAL

•  People are especially motivated to make a good first impression in their initial interactions with another person (Leary et al. 1994)

•  When eating with strangers than when eating with friends. –  eat less dessert (Clendenen, Herman & Polivy, 1994)

–  fewer snacks (Salvy, Jarrin, Paluch, Irfan & Pliner, 2007)


ANCHORING AND ADJUSTING

•  People use first impressions of others to “anchor” their own behavior.

•  Anchors are reference points that create an easy way to determine appropriate behavior

•  People adjust their behavior from the anchor to more closely match the values of their friends


VALUES

•  Values focus on ideals and are central to the self, represent enduring goals.

•  Serve as standards for judging others’ (and one’s own) behavior

•  Motivate behavior •  Help us decide on one course of action vs.

another


DO COLLEGE ROOMMATES ACT THIS WAY IN REAL LIFE?

•  Measure both roommate’s eating habits over time

•  Research questions: 1  When are their habits most similar? 2  What causes their habits to change over

time?


Ruby’s after dinner snacking

Zoe’s after dinner snacking





September October November

TWO ROOMMATES


AFTER DINNER SNACKING

Snacking rates increasing and contribute to 25% of diet. (Jahns et al. 2001)

Snacking after dinner predicted weight gain in college students (Levitsky et al. 2004)


HYPOTHESES

•  H1: Roommates’ after dinner snacking will be highly similar when they first meet

•  H2: Roommates will change their snacking behavior to more closely match the values of their roommate


STUDY DESIGN

•  Longitudinal –  3 time points over 3 months

•  Dyadic –  Randomly assigned same-sex roommates –  65 female, 30 male pairs

•  Online Questionnaires


STUDY DESIGN

MEASURES

•  Self-report surveys of diet and exercise behavior

•  Objective measures of height and weight (T1 &T3)

•  Relationship quality

•  Values about diet and exercise



•  5. Over the last week, how many times did you eat a snack after dinner? Check ONE box. ◻ Never ◻ 1 time last week ◻ 2 times last week ◻ 3 times last week ◻ 4 times last week ◻ 5 times last week ◻ 6 times last week ◻ Everyday


WILL WE BECOME FRIENDS?

•  Inclusion of Other in the Self (IOS) Scale

•  INSTRUCTIONS: Please circle the picture below that best describes your relationship.


PERCEPTIONS OF VALUES

How important is it to you that you eat healthy everyday? 1 2 3 4 5 6 7

Not at all Very much

How much do you believe your roommate values the importance of eating healthy every day?

1 2 3 4 5 6 7 Not at all Very much


FINDINGS

•  Net weight gain of 2.1 pounds over 10 weeks

•  Total after dinner snacking predicted weight gain


BECOMING FRIENDS

•  Roommates who ate together more often became closer over time


WAS ROOMMATES’ SNACKING MOST SIMILAR WHEN THEY FIRST MET?

Item Sept Oct Nov

Snack after dinner .38** .13 .04

** Correlation is significant at p<.01








September October November


.38** .13 .04

.48**

.48**

.58**

.58**

ns ns



Comparison Group

September Correlation

Close .34*

Non-close .43**

Female .48**

Male .15

* Correlation is significant at p<.05,; **p<.01


Females Males Food Item Time 1 Time 1

Salad .51** .39* Vegetables .14 .28*

Fruit .11 0 Ice cream .20* 0

Cookies .32** .05 Candy .24* 0

Chocolate .24* .14 Fries .28* .0


WHAT FACTORS PREDICT CHANGE?

•  Do roommates adjust their behavior after an anchor has been established?



Own Exercise Value

Own Exercise Value


CONCLUSIONS

•  Previously unacquainted roommates appear to carefully monitor their after dinner snacking behavior to create a favorable first impression.


CONCLUSIONS

•  Roommates adjusted their after dinner snacking behavior over time to more closely match the perceived values of their roommate.


OTHER WEIGHT RELATED BEHAVIORS

•  Roommates socialized each other to become more similar in their sedentary behaviors over time.

•  A student’s healthy values predicted less breakfast consumption by their roommate.


IMPLICATIONS

•  Peer influence is often implicated in terms of encouraging risky and deviant behavior

•  Peers also can create norms that support and validate positive and healthy behaviors


APPLICATIONS

•  Social influence from valued relationship partners could be leveraged to sustain healthy behavior over time.

•  Diet buddies •  Work out training in friendship groups •  Regular communal meals


FUTURE RESEARCH

•  What are the longer term effects of peer influence on diet and exercise?

•  Can healthy diet and exercise norms spread among first year students living on campus?

•  To what extent do our close companions influence other factors such as happiness, personal goals and academic achievement?


THANK YOU!

Jhon Wlaschin [email protected]

www.jhonwlaschin.com


GENDER DIFFERENCES

•  Women tend to be more sensitive to their relationship partners than men

–  Provide more social support –  Possess greater empathic accuracy –  Think about and devote more time and effort

toward maintaining their relationships than men –  Women are more aware and have better

knowledge of nutrition than men (Kiefer, Rathmanner, & Kunze, 2005).


CLOSENESS AND INTERPERSONAL POWER

•  Assumed that close relationship partners are most likely to influence each other.

•  The partner who is least interested in the relationship is in a position of enhanced power since he or she will be most likely to dictate whether the relationship flourishes or dies.

Documents

PEER INFLUENCES ON WEIGHT GAIN: A NEW LOOK AT THE … · 2014. 10. 21. · predicted weight gain in college students (Levitsky et al. 2004) Jhon Wlaschin • Peer Socialization HYPOTHESES