Would you hand over email addresses if promised pizza? You're not alone. iStock

The majority of students are willing to sacrifice their friends' private email addresses in exchange for free pizza, according to a study of 3,108 Massachusetts Institute of Technology (MIT) students.

The National Bureau of Economic Research uncovered the paper, published in final format this week (14 June), studied the adoption of cryptocurrency on campus while measuring levels of privacy and trust in social groups. To look at how incentives played into the equation, the authors decided to use pizza as a tempting factor.

"Whereas people say they care about privacy, they are willing to relinquish private data quite easily when incentivised to do so," the study's authors found.

They used a randomised 50% sample where students would be asked for details of their close friends, with the test trying find out if they protected the privacy of their buddies by handing over fake information, or if the lure of the margarita was just too strong.

This inevitably split the group in half: 50% incentivised by pizza and 50% not. Who would come out on top?

The question read: "You have been selected for an additional, short survey (1 question). If you decide to complete the survey, you will receive one free pizza that you can share with your friends. List three friends you would like to share a pizza with. One pizza will be on us!"

It found that 98% of students in the incentivised sample handed over the credentials when promised pizza.

The analysis found the "incentivised condition has a large, negative effect on the probability that students will protect the privacy of their friends relative to their behaviour in the non-incentivised condition." It could be, however, the main factor driving the deal was pizza.

"The results [...] highlight how small incentives such as a cheese pizza can have a large effect on decisions about privacy," the study's working paper concluded. It also said "irrelevant, but reassuring" information about privacy protection makes people less likely to avoid surveillance.

Christian Catalini, one of three authors of the study, told Market Watch: "[It is] important to rethink how consent is given in all these applications, mostly to make sure that consumers are actually making a choice consistent with their preferences."

"As more of our lives are becoming digital, making sure we have control over how and when our data is used will become more important over time," he added.