Why You Should Travel With Prunes (You Kind of Know Already)

Even if you’ve never tried a prune, you know of their reputation. Grandparents keep prune juice in the fridge to keep them, er, regular. Younger backed-up relatives (read: your baby-boomer parents) may indulge in the dried plums to help them relieve themselves. And prunes can be useful for another crowd: constipated travelers.

Prunes, in case you didn’t already know, are a specific type of plum that have been dried. They’re sticky and sort of taste like a giant raisin.

Although it’s common knowledge that prunes can make you poop, this wasn’t verified by scientific literature until recently. Research into food and nutrition don’t always attract vast sums of research funding, says Roger A. Clemens, a professor at the USC School of Pharmacy. No studies mean no data, and without data scientists couldn’t say with any certainty that the laxative effect wasn’t just happenstance or placebo — they needed to be sure it was happening, and then they could figure out why. As the famous engineer and statistician W. Edwards Deming once said, “In God we trust, all others must bring data.” Food science is no different.

During the past few years, the California Dried Plum Board (yes, there was a conscious rebranding effort to call them dried plums instead of prunes) has invested in more research. This has revealed some of the ways that prunes might alleviate constipation.

See, prunes contain a lot of fiber — about six grams of it per a 100-gram serving of prunes (an apple only has 2.4 grams of fiber per 100 grams). But just the amount of fiber doesn’t explain prunes’ dramatic effect on the digestive system. They’ve also got lots of natural sugars in them, different than other types of dried fruits, which may stimulate friendly gut bacteria to produce compounds that act as lubricants, allowing stool to pass easier, Clemens says. Because prunes are fruits, they also bring water to the digestive tract, which has the same sort of lubricating effect.

Prunes make a great on-the-road snack — they don’t require refrigeration and aren’t messy to eat. “You can take them anywhere. You can even get them through TSA,” Clemens adds.

And that’s particularly useful for people who find themselves afflicted with traveler’s constipation, which may affect 40 percent of people who travel. Lots of factors can cause traveler’s constipation, ranging from the psychological (a disrupted routine, unfamiliar bathrooms) and physical (not drinking enough water, eating differently than normal, etc.). And that’s just considering domestic travel — add in different time zones, exotic foods, and a new environment, and of course things are going to get out of whack. “As we travel internationally, people’s gastrointestinal irregularities change. [Eating prunes] could be something that could assist you in maintaining good GI health,” Clemens says.

This all sounds good in theory, but don’t take science’s word for it. Take mine!

Luckily for you, dear reader, I had a road trip coming up — a drive a few hours north to Vermont — and although I have personally never gotten traveler’s constipation (and, in fact, had never knowingly eaten a prune), I decided to try it out for myself.

Clemens suggested that I eat some the day before my drive to see how a few would affect me. On the day of the drive, and each day of my trip, I ate two prunes a day. I didn’t notice any big differences digestively, but I was regular as a Swiss watch, and the prunes were a surprisingly popular car snack.

Researchers still have more questions about how prunes affect people. How many prunes is the right dose if you want to be healthy, and how many do you need to have a laxative effect? What causes the variation in people’s reaction to prunes — some might have some gastric discomfort (read: diarrhea) from five prunes, but others can eat 10 without issue?

But you don’t need all those answers to pack a few in your suitcase … just in case you end up having a hard time going while you’re on the go.

In related stomach trouble news: Coca-Cola Is My Secret to Battling Traveler’s Tummy