Does food environment influence food choices? A geographical analysis through “tweets”

• We collect food activities on Twitter and identify food environment around them.
• Healthiness of food activities is correlated with quality of food environment.
• Density of grocery stores influences individuals to make healthful food choices.
• Density of fast food restaurants may not discourage healthful food choices.

Access to nutritious food is imperative to physical well-being and quality of life. Previous food environment studies have revealed a disparity of access to healthful food on various geographical scales. An overlooked facet of this spatial perspective is the impact of the food environment at the individual level. Individuals tend to make diverse food purchasing and dining choices, including where, when, how, and which types of food to acquire. An unexplored avenue for further investigation is measuring the extent to which people's preference for food is elicited by exposure to their immediate food environment. This paper takes an innovative approach to this question by soliciting individual data about food-related activities from social media, or specifically, “tweets” (messages sent on Twitter). With spatiotemporally tagged information, tweets provide an ideal method for measuring the exposure to the food environment in real time. This measure, as a representative of individual food access, is associated with users' particular diet choices conveyed in their tweets. By comparing groups of Twitter users who shop in grocery stores to those who dine at fast food restaurants, we found that the prevalence of grocery stores that stock fresh produce within an individual's neighborhood may significantly influence him or her to make nutritious food choices. This study has a great potential to inform health professionals and stakeholders of the significance of social media in assisting with crowdsourcing human subject data that incorporate spatiotemporal dimensions and to explore individual diets in relation to their perceived food environment, which can positively impact the health of communities.