If you were to bet someone over who is more likely to call in sick to work, heavy drinkers or people who don’t touch alcohol, the smart money might say to pick the drinkers, right? Wrong.

Researchers in Finland have found abstainers are just as likely to call out of work as those who love their liquor. The reasons why might surprise you.

The team looked at surveys of more than 47,000 Europeans who answered health and lifestyle questions. They identified nondrinkers, moderate drinkers and heavy imbibers. Moderate drinkers were women who drank one to 11 units of alcohol each week; for men, it was one to 34 units. Heavy drinkers tossed back more than 11 and 34, respectively.

A unit was defined as containing 8 grams of alcohol. A standard glass of wine thus was two units, a pint of beer was just under two units. Therefore, a woman who has between five and six glasses of wine or beer a week was a moderate drinker; for a man, it was up to 17 pints or glasses of wine.

Heavy drinkers put away more than that, so it’s not a shock that they may have a hard time answering the alarm clock in the morning. But what about those who never touch the stuff?

For them, the issue wasn’t alcohol, it was their health. The nondrinkers cited mental and musculoskeletal disorders and diseases of the digestive and respiratory system as reasons for missing work. Also, many medical treatments prohibit alcohol use.

The researchers noted they relied on self-reported data, which is not always 100 percent accurate. The results also show there may be any number of alternate explanations for seemingly obvious situations, so think twice before making that bet based on gut instincts.