Deakin University

File(s) under permanent embargo

The Effects of Social Setting and Portion Size on Food Consumption Amount

conference contribution
posted on 2015-01-01, 00:00 authored by M C T Tan, P Dubelaar, N Zlatevska
How much a person eats has always been explained by an individual’s
hunger and satiety level (Vartanian et al., 2008). In the
1960s, scholars first discovered non-physiological factors would better
predict the amount of food a person will consume (Schachter et
al., 1968; Stunkard & Koch, 1964). Existing literature shows that
consumers’ food consumption behaviours are influenced by a number
of distinctive contextual cues. These can be divided into personal
contextual cues, consumption contextual cues, and food contextual
cues. Individuals often seek norms of appropriateness from these
contextual cues in eating events (Herman & Polivy, 2005). This research
manipulates social settings and portion size, which are identified
as important consumption contextual cues and food contextual
cues respectively. Other contextual cues are kept constant by using
an experimental method.
Consumer preferences and marketing efforts are largely characterised
by the advantages of larger portion size offerings (Dubois
et al., 2012). Portion size is widely recognised as having a profound
impact on the amount consumed (Zlatevska et al., 2014). In contrast,
it is less clear as to what effect eating with others has on the amount
consumed. Studies have reported people consumed both more and
less as a result of eating in a group (Herman et al., 2003). Most food
is offered in different portion sizes and consumed in a social setting.
Whether or not the effect of portion size will be influenced by social
setting remain unanswered.
This research aims to better understand how portion size and
social effects jointly affect the amount an individual is likely to consume.
The research questions include: Will there be an interaction
between portion size effect and social effect? Will personal characteristics
moderate the effect of portion size and social influence?
What is the effect of social influence when known context effects are
controlled? These research gaps in the existing literature are important
as both portion size and social effects are recognised as some of
the most important contextual cues in the literature. These contextual
cues were reported to have profound impact on an individual’s
consumption amount. The understanding of the combined effect, its
moderator, and directionality of these contextual cues is an important
advancement in the current knowledge. Social effect was reported to
be stronger for people with low self-esteem (McFerran et al., 2010).
Hermans and colleagues (2009; 2012) show mixed results regarding
correlations between restrained eating and amount consumed. Therefore,
personal contextual cues are measured to examine moderation
In the face of the possible bi-directionality of social influence on
the amount consumed by an individual, an experimental study design
was used to keep various other contextual cues constant. A cover
story was used in this research; participants signed up for a study
that explores consumers’ choices of holiday destination. Participants
were seated at a round table in a classroom, and were given some
group activities related to the cover story to induce rapport. Eating
was incidental to participating in this study. Participants signed up
for the experiment on a voluntary basis and were awarded course
credit. An experimental design with two (portion size: small, large)
by two (social setting: alone eating, social eating) between subject
design was used.
This research consisted of two studies using different types of
food. The food used in Study 1 was Arnott’s Nice cookies and the
food used in Study 2 was MARS M&M’s chocolates. The cookies
and chocolates in both studies were served in sealed, clear plastic
containers that were opened for the participants by the experimenter.
Each container was weighed before and after the experiment. In
Study 1 (cookies), results show that individuals’ consumption is affected
by the social



Association for Consumer Research


Hong Kong, China

Place of publication

Duluth, Minn.

Start date


End date


Publication classification

EN Other conference paper


E Wan, M Zhang

Title of proceedings

Proceedings of the Asia Pacific Association for Consumer Research Conference 2015

Usage metrics