Here is a tip for anyone who works in marketing, a small amount of infidelity can increase someone’s brand loyalty. In non-marketing terms, a loyal fan of Dunkin Donuts, who is forced to drink Starbucks because there is not a Dunkin Donuts around, will leave the Starbucks loving Dunkin Donuts more than ever.

“That feeling that you have of  I’m not sure I should be doing this, actually sometimes can make you go back to the regular brand,” said Harvard Business School Professor Michael Norton on Boston Public Radio Monday.

Norton was one of the members of the research team who discovered this phenomenon. While conducting their marketing study, the researchers would give a subject the option to watch either 10 minutes of commercials for a brand they liked or 10 seconds of a commercial for a competing brand they did not like. Since the subject would not want to watch ten minutes of commercials, they would inevitably watch the 10 second one. The researchers found that this small flirtation with a competing brand strengthened their devotion for their desired brand.

“It only works for people who really care about their brand,” said Norton. “Sometimes when we become really attached to a brand, when we really think this is a part of who I am, those are the brands where we love them, but sometimes if we stray just a tiny bit we might love them even more when we comeback.”

Norton says this emotional connection to our favorite brands can cause us to feel guilty when we flirt with the idea of trying out something else. This guilt pushes us to show greater appreciation towards the brands we love.

“It seems silly that we feel so emotionally attached to brands but think of people with their car brands. I mean we can think of, I don’t mean to stereotype, but old guys who the idea of buying anything but a ford or a Chevy, it would be like a sin. They can’t even imagine that somebody would do that,” said Norton. “Even though your free to do what ever you want, brands have that emotional hold over us that make us do things as though we are dealing with people, even though in the end it is just a truck."

This same idea can, surprisingly enough, also be applied to relationships.

“So imagine you’re at a dinner party, you’re with your partner, but a little bit of flirting is going on with somebody else at the table.  Just kind of innocuous flirting. you might have a more exciting interesting evening than you would have otherwise if you just sat and stared at your TV, and maybe you’ll transfer some of that excitement back to your partner rather than to the person your flirting with,” said Norton.

Listen to the complete interview with Michael Norton above.