Why your poop gets weird on vacation—and what to do about it

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. 

The good news is that traveler’s diarrhea or other complications can be prevented. There are a few tried-and-true ways to put a firm stop to this backdoor problem.

Feces factors

Many aspects of traveling can increase the chances for bowel movement issues, says Sunana Sohi, a gastroenterologist at Gastroenterology Health Partners in Louisville, Kentucky. Most of those problems—whether they result in constipation or diarrhea—should resolve once you get back to a normal life routine. 

Sitting

Sitting for long periods, which could be spending hours on a car or a plane, compresses the abdominal organs. This squeeze slows down digestion because it reduces peristaltic function—the muscle contractions needed to physically move food down the digestive tract. With your gastrointestinal tract not working at full capacity, you’re more likely to produce gas, bloating, abdominal pain, constipation, and diarrhea.

[Related: What to do when you’re trying not to poop]

Jet lag 

Adjusting to different time zones affects your circadian rhythm, the 24-hour biological clock that regulates digestion and other bodily cycles. The circadian rhythm communicates with certain members of your microbiome and synchronizes activities to align with when you eat or fast. This also includes when you typically go to the bathroom. Most healthy guts keep a consistent schedule for daily bowel movements.

But traveling to new time zones messes with your internal clock, which might throw your body out of sync with your usual poop schedule. Back home you may have a morning bowel movement, but until your vacation body catches up to local time, that a.m. poop might be when you’ve fallen asleep. “Any time differences or changes in your schedule where you are getting up earlier than usual or sleeping in later can throw off the regularity of bowel movements, leading people to be constipated,” Sohi explains.

Sleep

Not getting enough sleep can lead to a less healthy microbiome. When you’re adjusting to a new schedule, it can be a challenge to get in your usual Z’s. This poor sleep can translate to digestive problems—as diverse as diarrhea to abdominal pain—because it increases the risk for inflammation in the gut and ups your cravings for sugary foods.

New foods 

Depending on your microbiome’s composition, Dhir says trying a new herb or spice in your food is enough to back up the time it takes for food to pass through the bowels. This is because unfamiliar cuisine can irritate gut microbes, which are not used to processing the ingredients. 

Stress

As exciting as travel can be, it also comes with its own stresses—whether you’re trying to pack and prepare or get your bearings in a new country. Excess stress makes the gut barrier vulnerable, opening it up for dangerous bacteria to enter and increase inflammation.

Dehydration

Most travelers do not drink their usual amounts of water, says Sohi. When traveling, there may not be as easy access to potable water compared to the supply on hand at home. Even if you do have water, there may be a concern whether a bathroom is nearby. 

Bowel diseases and age

People with irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are more sensitive to motility issues and flare-ups, Sohi and Dhir note. Since women are more likely than men to have IBS issues, they are often the ones who experience bowel movement changes, Sohi points out.

Age may also play a role, too, she says. Because the digestive process slows down as you grow older, food moves more sluggishly through the colon and has more opportunity to cause problems.

Avoiding upsets

There are several methods you can take to prevent traveler’s diarrhea and constipation.

Adjust early

If you’re traveling across time zones, don’t wait until a trip begins to start adjusting to the difference. A few days before your trip, you can start gradually changing your routines to  get your body acclimated to the shift in time. You’ll also want to make sure you’re not skipping out on sleep in the days leading up to the trip. Since the body’s circadian rhythm influences gut motility, Dhir says getting much needed shut-eye will help keep digestive processes running smoothly.

[Related: Look inside London’s new Super Sewer, an engineering marvel for rubbish and poo]

Stay hydrated

Water keeps food moving through your system, which Dhir says is critically important to the health of your stool—poop is 75 percent H₂O. “Although travel often prompts you to increase your intake of alcohol or caffeine while traveling,” he says, “keep in mind that these beverages can also dehydrate you, affecting your bowel movement frequency and quality.”

Move your body

Make sure to get up at least once every hour if you’re sitting on a plane or train. If you’re in a car, schedule breaks to stretch your legs and walk around. Dhir says movement is important in increasing blood flow to the intestines, which can help promote regular bowel movements and ease constipation symptoms. 

Eat fiber 

People eat and drink for pleasure on vacation, and these food choices may not always be the best options for your gut. While treating yourself to fun meals is a major travel perk, you’ll want to make sure you’re still consuming enough fiber for healthy stool consistency. On the go, Dhir recommends berries, nuts, seeds, and other fiber-rich snacks.

Consider probiotics 

Probiotics are microorganisms that maintain the health of the “good” bacteria in your gut. “Probiotics supply gut-friendly benefits, like supporting regular bowel movements and including ease from occasional bloating and can promote gastrointestinal resilience in periods of disruption,” Dhir says. Research shows consuming probiotics regularly can help build immunity and keep out dangerous pathogens.