Leaving on a jet plane: Probiotics for travelers

You have finally managed to successfully pack everything you need for your trip into your carry-on suitcase.

You have printed your e-tickets, hotel reservation information, and trip itinerary. You have your ID and passport handy for airport security. By all accounts, you should be ready for that trip you so carefully planned. You even remembered to bring your phone charger this time.

You may think that you are all ready to fly the friendly skies to your travel destination. However, you would be very smart to also take probiotics to lower your risk for traveler’s diarrhea.

What are probiotics, and why are they popular?

Probiotics, sometimes referred to as “good bacteria,” are very similar to certain micro-organisms found in the human gastro-intestinal (GI) tract that help keep it healthy.² When we ingest probiotic supplements, or certain foods that naturally contain probiotics, we are upping the body’s natural ability to ward off certain GI problems, such as diarrhea.

The nice thing about probiotics is that they are easy to find in common foods (such as yogurt), and have few adverse side effects², making them popular. According to the 2012 National Health Interview Survey, four million adults used probiotics during any given 30-day period.³ It was the third most popular supplement among adults, ranking behind omega-3 fish oil and glucosamine/chondroitin.

What causes traveler’s diarrhea?

Traveler’s diarrhea in particular is due to unsanitary conditions while traveling in developing areas of the world, such as Africa, the Middle East, Central America, Mexico, and parts of Asia.¹ Depending on the geographical location, rates of traveler’s diarrhea can range anywhere from 5 percent to 50 percent.⁴ The Centers for Disease Control & Prevention (CDC) states that, while the condition is usually not life-threatening, there are some measures people can take to lower their risk of contracting the disease:

• Only eat hot, cooked food that has not been sitting out for an extended period of time
• Only eat raw fruits and vegetables if you have thoroughly washed them in clean water
• Only drink beverages from factory-sealed containers¹

The CDC further recommends fluid replacement, antibiotics, and some over-the-counter preparations to help treat traveler’s diarrhea once it is underway.¹

What does the research say?

A meta-analysis study published in a special issue of the journal Travel Medicine and Infectious Disease pooled data from 940 studies on the efficacy of probiotics for preventing traveler’s diarrhea.⁴ Pooling the data allows for researchers to see patterns across smaller studies. In this case, 12 smaller studies met the meta-analysis inclusion criteria. The researchers found that several types of probiotics (Saccharomyces boulardii and a mixture of Lactobacillus acidophilus and Bifidobacterium bifidum) significantly prevented the onset of traveler’s diarrhea.⁴ They also found no serious adverse effects from using the probiotics.

A review article from the Pediatric Infectious Disease Journal found that probiotics provided lower rates of traveler’s diarrhea than among controls.⁵ These rates ranged anywhere from 38 percent (compared to 43 percent of controls) to as low as 3.9 percent (compared to 7.4 percent of controls).

The truth is that Americans are choosing to travel to more off-beat locations. A CNN poll found that half of the top 10 travel destinations were located either in Asia or the Middle East.⁶ In fact, Bangkok was the second most popular destination, hot on the heels of London.

Given Americans’ more adventuresome travel spirits, it should not be surprising that probiotics are a popular, easy way to reduce the risk of contracting traveler’s diarrhea when on the go to these exotic locales.

1. Traveler’s diarrhea. Centers for Disease Control & Prevention. Accessed 11/22/2015.
2. Schaeffer J. Friendly bug invasion. Today’s Dietician 15(9):38.
3. Most used natural products. 2012 National Health Interview Survey. Accessed 11/22/2015.
4. McFarland LV. Meta-analysis of probiotics for the prevention of traveler’s diarrhea. Travel Med Infect Dis 2007 Mar;5(2):97-105.
5. Teitelbaum J. Probiotics and the treatment of infectious diarrhea. Pediatr Infect Dis J 2005;24(3):267-268.
6. 10 most popular cities for travelers in 2015. CNN. Accessed 11/22/2015.