However proud an Osaka sushi chef is of the pristine quality of his raw seafood, shellfish, which are bottom feeders, pick up a lot of nasty bacteria, and if uncooked, they can easily be transferred to you. Cooking should kill most of them off, and the fish used for sashimi is pretty safe. But eating raw oysters or mussels anywhere can be hazardous. Oyster-causing hepatitis can be a killer that destroys your liver (and thereby your ability to drink alcohol). You can also get a tapeworm from eating contaminated raw meat.
Next time you enjoy a nice haunch of venison at a restaurant in the U.S., rest assured it came - by law - from an inspected game farm. Wild game, even trout from crystalline Alaskan rivers, may contain badass bacteria, and before you eat what you kill in the wild, you'd better be damn sure the animal was healthy. If you do see "wild game" on a menu, then it was most probably venison or grouse that was shot in Scotland and approved for sale by a game inspector. One of the best, most reliable sources for wild game is D'Artagnan Foods, which imports inspected foods including Scottish pheasant, redlegged partridge, grouse and wood pigeon.
Every guidebook to a foreign country stresses not eating unwashed, uncooked vegetables and fruits. And too many people have done so anyway at their peril and ended up sick as a dog from salmonella, cyclospora, campylobacter, and more. You can wash and scrub and peel raw fruits and vegetables and remove the outer bacteria, but that won't kill what's inside. Boiling and cooking is more advisable. And watch out for desserts, too, that may have raw fruit in or around them. Order a nice slice of apple pie instead.
Some Americans still harbor an irrational fear about eating pork that has not been cooked to shoe leather supposedly to kill off the trichinosis larvae. The fact is, there are fewer than a dozen reported cases of trichinosis in the U.S. each year, and all of them come from eating wild game, including a wild hog. Hog production in the U.S. is extremely hygienic, so cooking your pig till pink is just fine. But in the rest of the world, particularly in developing countries, such hygiene is not standard practice, so only eat pork there that has been thoroughly cooked through to 160 degrees F.
Bet you didn't know that half of all egg-related illnesses, mainly salmonella, are picked up in restaurants, including in the U.S. The problem is in the chicken that lays them, not the shell itself, though this should be thoroughly washed, something that cannot be counted on abroad, where a freshly laid egg is cherished. That means no Caesar salads abroad and no steak tartar with a raw egg in it. Forget the raw steak too.
It used to be a rubric when traveling abroad not to drink the water, even in Europe. But this has largely become irrelevant if you're staying in a city like Paris, Stockholm, or Tokyo, where the better hotels filter their water. Nevertheless, unless you ask, you won't know that, and even brushing your teeth with contaminated water is going to be bad news. Bottled water is crucial when traveling, and the more familiar the label on the bottle, the better off you'll be. Drinking from a fountain is very stupid. A friend of mine recently spent three weeks in spasmodic pain just because he caught a wave of river water in his mouth while sailing through Bangkok.
If you're taking a pleasant cruise down the Amazon with a reputable outfitter, you probably don't need to be told about chicha. But just in case you are invited by some local tribesmen anywhere in the Amazon Basin to knock back a tot of chicha, do anything to avoid it. Chicha comes in many forms, but it always involves saliva. In some cases the cassava root is chewed by the tribeswomen and the juice spat into a bowl that is left to ferment into alcohol. The honor of drinking chicha is one that may follow you home for the next several months.