Drink only bottled water, beverages made with water that you know has been boiled, or drinks from sealed bottles. Make sure the bottle has an intact seal before you open it (otherwise, it's likely that the bottle was filled with tap water). Ask that coffee or tea be made with boiling water, not just hot water. Before you travel, it may be worth investing in a portable UV water purifier such as the Steripen, so that you can make your own safe drinking water. These pocket-sized devices remove at least 99.9 percent of pathogens.
Tap water or ice made from tap water may be found in some foods and beverages you may not think to worry about, including ice cream, fruit juices or smoothies diluted with water, frozen sweet beverages, ice pops, fountain drinks, or sodas that don’t come from a sealed bottle. You should also be on the lookout for unpasteurized (raw) milk or dairy products made from unpasteurized milk, such as ice cream or cheese. If you’re not sure, ask.
Avoid raw fruit unless it’s something you peel yourself, like a banana or orange. Forget about cold salads; eat vegetables only if they are cooked and piping hot. Note that contaminated fruit and veggies may make their way to your plate even if you didn’t order them. For example, your hot entree may have a fresh fruit or vegetable garnish. Don’t eat these, or better yet, ask that any uncooked garnishes be left off the plate. Even chutneys and salsas should be avoided, since they’re generally made with raw fresh fruit or vegetables.
Even if the food was hot when it was prepared, allowing it to sit on the buffet table can expose it to flies, which can carry a variety of bacteria. In addition, cross-contamination can be rampant at buffet tables, where contaminated food or its juices can easily come in contact with other food items. There's also a risk that patrons with unwashed hands may touch utensils or food, resulting in bacteria or viruses making their way into your dish.
This is a hard one to follow; eating what the locals eat is so very tempting, both for getting an authentic experience of your destination and because the tastes and flavors can be so amazing. But street food has many potential risks, including vendors’ hands that may or may not be clean, microbes that may contaminate the utensils and the surfaces used to prepare and cook the food, and potentially inadequate cooking times or temperatures. Even if a food stand looks very clean, it's safest to avoid it.
Before eating, wash your hands thoroughly using soap and water or, if none is available, a hand sanitizer containing at least 60 percent alcohol. To be even safer, bring your own utensils and wash them often with soap and water. You can bring cheap plastic ones, of course, or sturdy models that travel well and can be purchased at any store that sells camping supplies. Be sure to use bottled or disinfected water for washing them.
This over-the-counter medication can cut the risk of traveler’s diarrhea by as much as 50 percent. The CDC and many health professionals advise chewing two tablets (or consuming the liquid equivalent) when you arrive at your destination, before your first meal; repeat before every subsequent meal and at bedtime. The regimen has to be precisely followed in order to work. Check with your doctor to make sure it’s safe for you to take Pepto-Bismol this way; people who have certain health conditions or take certain medications may need to avoid it.
Consider downloading the CDC’s Can I Eat This? mobile app, which is designed to help people avoid stomach troubles while traveling. You select the country you’re visiting and the app tells you what’s safe using a series of multiple-choice screens. It’s available for Apple and Android mobile devices.