BEHAVIORAL ANALYSIS OF SNS USERS WITH REGARD
Masashi Sugano and Chie Yamazaki
School of Comprehensive Rehabilitation, Osaka Prefecture University
3-7-30, Habikino, Habikino-shi, Osaka 5838555, Japan
In this paper, we verify the behavior of Social Networking Service (SNS) users who focus on diet and clarify points for
utilizing such a SNS more effectively. We analyzed the utilization of Yahoo Diet Diary by 2500 users. As a result, we
clarified the characteristics of users who were long-time users of the SNS and found that weight loss over 90 days from
the start of using the service was significant. Moreover, we revealed the characteristics of users who experienced
significant weight loss through active communication via the SNS. The study also showed that significant weight loss
and posting messages frequently were characteristics of users who actively communicated through the SNS.
Social network service, health care, diet, behavior change
Communication via a Social Networking Service (SNS) which is a community-type website that promotes
and supports relationships between people has spread in recent years. SNSs, such as Facebook and Twitter,
offer a means and place for smooth communication between friends and acquaintances. Moreover, the
mechanism for building new relationships can be made based on commonalities between users; for example,
hobbies, inhabitable areas, alma mater, or a friend’s friend. These SNS applications can be used not only just
for communication but also other things such as tools for health care or improving diet and lifestyle (Hawn,
2009). For diet or lifestyle improvement, aspects of one’s personal life, like meals and exercise, can be
recorded and validated by oneself to reflect on at a later date (De Silva, 2007). Furthermore, by releasing this
information through an SNS, information exchange with others and sharing the results of lifestyle
improvements are facilitated (Swan, 2009). When the interaction of a person with this type of SNS promotes
behavioral modification, it is expectable to have a marked effect on lifestyle improvement. In this research,
we clarify the validity of such an SNS by investigating the situations and behavioral modifications of users
focusing on diet through an SNS.
We chose the Yahoo Diet Diary as the SNS for investigation. Yahoo Diet Diary is an SNS equipped with a
self-management tool for recording aspects such as weight and meals on a daily basis over a continuous
period of 90 days (these 90 days are defined as one “stage”) and enables communication through user diaries.
Moreover, it is possible to create a group community called a “club” or to register a user with similar age and
habitus as a “rival”. First, we randomly selected 50 women who used the system for six months or more, and
the number of stages in which the system was used continuously ranged from 1–10 (equivalent to 500
women). From user diary content, we investigated weight loss, meal recording points, age, and weight at the
time of starting a diary. In order to clarify the relationship between the number of rivals and user
characteristics, we investigated the number of continuous utilization stages about 2000 users from the top
about the number of rivals. Next, we classified users into those with many rivals and those with few rivals
and investigated the significant differences between weight loss, meal recording points, diary entry frequency,
number of viewable photographs, and the number of the clubs to which each user belonged.
Figure 1 shows the relationship between the number of stages in which the system was used continuously and
weight loss per stage. Weight loss in stage 1 was the highest (average of 3.0 kg) and decreased as stages
progressed. After stage 5, changes in weight loss were negligible. Next, we investigated the relationship
between weight loss and the number of continuous stages while only paying attention to weight loss in stage
1 (Fig. 2), and a correlation was revealed (Spearman rank correlation coefficient: rs=0.73, p<0.05). It became
clear that long-term users of the system had the highest weight loss.
Figure 1. Relationship between number of stages and weight loss per stage
Figure 2. Relationship between number of stages and weight loss in stage 1
Next, we show the average and 95% confidence interval with respect to weight loss (Fig. 3) in users who
completed each stage from stage 1 to 10. Average weight loss per stage was 1.3 kg, and weight loss of users
who completed all 10 stages was 4.3 kg. These results clarified that weight loss was greatest for continuous
long-term users of the SNS.
Results for the number of stages and average age are shown in Fig. 4, which revealed that the number of
stages increased in line with age. Since older users had more available time in which to use the SNS so their
diary entry frequency was high. Moreover, this SNS can be considered a new facility for communicating with
others who enjoy using an SNS diary.
Figure 3. Weight loss per stage
Figure 4. Relationship between utilization period and age
Next, we investigated the relationship between the number of rivals and the number of continuous stages (Fig.
5). An association was seen for users with a short utilization period and number of rivals. In addition, there
was a variation between users with a large number of rivals and those with few rivals, and it became clear
that variation occurred as the number of stages increased. We then showed the effect of different numbers of
rivals (Table 1) while paying attention to users in stage 11. A significant difference was seen between women
with few and many rivals for weight loss, number of joined clubs, number of viewable photographs, and
diary entry frequency, although height and weight for both groups were close to the standard values for
Japanese women. When a user registered a rival, it became clear that there was a trend for choosing users
with the following characteristics:
(1) Those who considered that the effect of using an SNS is beneficial because weight loss is high
(2) Those who filled in their diary frequently and exhibited many photographs
Figure 5. Relationship between number of stages in which SNS was used continuously and number of rivals
Table 1. Differences in characteristics of users with many rivals and few rivals
Number of Rivals
Weight at time of starting stage 11 (kg)
Weight loss (kg)
Meal recording points
Number of clubs to which a user belongs
Number of photographs
Number of recorded entry dates in diary
In this study, we showed that weight loss is high in the early stage of utilizing the SNS, leading to an
improvement in motivation when the system is used continuously. Moreover, it was considered that
communicating actively with other users could improve the willingness to continue a diet by registering
rivals. In a future study, we plan to investigate the combined effect of SNS utilization and exercise.
De Silva, G.C., et al, 2007. An Interactive Multimedia Diary for the Home. IEEE Computer, Special issue on human
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Hawn, C., 2009. Take Two Aspirin and Tweet Me in the Morning: How Twitter, Facebook, and Other Social Media Are
Reshaping Health Care. Health Affairs, Vol. 28, No. 2, pp. 361-368.
Swan, M., 2009. Emerging Patient-Driven Health Care Models: An Examination of Health Social Networks, Consumer
Personalized Medicine and Quantified Self-Tracking. International Journal of Environmental Research and Public
Health, Vol. 6, No. 2, pp. 492-525.