This thesis explores the intersection of a long-standing public opinion theory – the spiral of silence – and the recent explosion in social publishing tools such as Tumblr and Twitter. It uses real-world discussion settings (including face-to-face focus groups and synchronous online discussions) in tandem with a pre-test/post-test methodology to measure opinion shifts on the topic of corn syrup and childhood nutrition/obesity. This research design is based on well-established criticisms challenging that the spiral of silence may not be fully explained by a national climate of opinion on a topic, suggesting that there are other influences on individual beliefs than just popular opinion. This thesis investigates the role of social media on opinion-forming variables, the role of the social publishing platforms themselves on opinion-forming variables and the manifest application of the spiral of silence within these environments. The hypotheses were not supported by the research and did not yield statistically significant variance, but statistically significant patterns emerged that demonstrate the need for further research in this area that builds on the research methodology across a more extended time span.