We’ve all heard the old wives’ tales about waiting an hour after we eat to take a swim. But what about driving? How does a full stomach, especially after a holiday feast, effect your behavior and attention span on the road?

An article in Country Living magazine provides interesting insight into how eating a big, carb-heavy, salty holiday meal can lead to the same type of drowsiness that can slow down our reaction times behind the wheel – much like the effects of alcohol.

Nutritionist Jenny Tschiesche talks about a study by breakdown specialists, Green Flag, which found 87% of us will experience festive food lag due to over-indulging, and three hours after we’ve eaten our  holiday feast is the most dangerous time to jump in the driver’s seat.

“People reporting desperate tiredness after their Christmas dinner isn’t surprising considering the amount of carbohydrates we’ll consume on Christmas Day,” Tschiesche said. “”Similarly, the sluggishness people experience is caused because there’s a high salt content in our festive treats, and this makes our bodies retain water.”

“The most dangerous time to drive is three hours after eating,” she said. “That’s because most of us have a metabolic rate of about three hours, so this is the point where we will feel the most tired.”

Click here to read the full article on CountryLiving.com.