Service with a smile sounds like a good idea. Not only do customers appreciate happy, friendly workers waiting on them, but there's also evidence that smiling makes you feel happy.

But, insisting that employees paste on a fake smile all day comes with a price. According to new research conducted by researchers at Penn State and the University of Buffalo, workers who feel like they need to force a smile are more likely to drink heavily as soon as they're off the clock.

The study, which was published in the Journal of Occupational Health Psychology, examined individuals who work with the public. Teachers, nurses, and food service workers were among the professions they examined.

Individuals who work with the public often have to force a smile regardless of how they feel. Additionally, their job success often depends on their ability to suppress negative emotions--such as resisting the urge to roll their eyes.

Their income also likely depends on their ability to smile and act as though the customer is always right--even when fielding complaints that are out of their control.

Smiling and acting sensitive to everyone's needs (while suppressing their own emotions) may yield a higher tip or better feedback ratings.

The researchers refer to this as "surface acting." They found that surface acting wears down employees and drains their willpower. Consequently, they lack the self-control they need to say no to alcohol after work.

The study found that those individuals were at a higher risk of drinking heavily once they clocked out of their jobs.

In a press release for Penn State, Alicia Grandey, professor of psychology at Penn State said, "It wasn't just feeling badly that makes them reach for a drink. Instead, the more they have to control their negative emotions at work, the less they are able to control their alcohol intake after work."

The researchers found that this was especially true for people who didn't find their work to be personally rewarding. Someone who serves food and forces a smile in an attempt to earn a bigger tip, for example, is likely to feel more drained than a nurse who finds that smiling at patients provides a sense of satisfaction.

What to Do About It

Whether you work as a flight attendant or you work in retail, pay attention to your drinking habits. Acknowledge how forcing a smile is likely to drain you of the mental strength you need to be self-disciplined outside the office.

Simply recognizing the link--and the potential risks involved--could help you make better decisions. Perhaps you decide to skip happy hour with your co-workers after work. Or maybe you decide to put a limit on how many drinks you consume each week.

If you're a boss, it's also important to recognize the risks your employees might face. Holding conversations about how hard it is to pretend the "customer is always right" might help everyone understand just how draining surface acting is.

It could also be helpful to give employees a little more autonomy. Rather than yell at an employee for rolling their eyes or reprimand someone who looks a little grumpy, think about how their interactions may help them blow off some steam at work--which might prevent them from drinking too much after work.