No one wants to travel to a fun or exotic location only to be stuck on the toilet. While bad shellfish from a cruise buffet could be the source of tummy trouble, taking a trip itself is also a factor that can change bowel movements. That's because when you travel, so does your gut microbiome. 

Your digestive tract is home to trillions of different bacteria, viruses, and fungi—all of which might be disturbed by a jaunt to a new locale. "Just like you, they're affected by shifts to your sleep schedule, changes in diet, exposure to new microbes, and excess stress," explains Raja Dhir, the co-CEO of the microbiome company Seed Health. How these microbes respond to those shifts can lead to overactive bowels.