This paper presents an online prospective study investigating whether the strength of social feedback, i.e. the proportion of persons who concur or do not concur with one's own answer to a question, influences the way one answers health-related questions. Two hundred and twenty-seven undergraduate students were recruited to use an online search engine to answer six health-related questions. Subjects recorded their pre- and post-search answers to each question and their level of confidence in these answers. After answering each question post-search, subjects were presented with a summary of post-search answers provided by previous subjects and were asked to answer the question again. There was a statistically significant relationship between the absolute number of others with a different answer (the crowd's opinion volume) and the likelihood of an individual changing an answer (P < .0001). Subjects' likelihood of changing answer increased as the percentage of others with a different answer (the crowd's opinion density) increased (P = 0.047). Overall, 98.3% of subjects did not change their answer when it concurred with the majority (i.e. > 50%) of subjects. When subjects had a post-search answer that did not concur with the majority, they were 24% more likely to change answer than those with answers that concurred (P < .0001). This study provides empirical evidence that strength of social feedback influences the way healthcare consumers answer health-related questions.