Trust Me: Adventurous Or Not, You Won't Starve.

Street meats in a market stall

Without throwing all caution to the wind it's easy enough to be somewhat adventurous about food while traveling in Thailand. You'd be foolish not to take into consideration that the Thai have systems that handle some things better than we do; perfectly natural, since they've grown up with them - bacteria and the likes - and developed a tolerance a lot of us don't have when stepping off the plane there. 

That said, there's absolutely NO reason why you have restrict your meals to the hotel buffet, familiar items at a grocery or 7-11 store or - ick - at McDonald's or another packaged food chain restaurant.  You just have to be willing to learn and adjust. Some pre-trip research is always a good idea. Might save you diving into something that might surprise you.

Take the innocent looking chili sauce, for a start. Some visitors can't tolerate the highly spiced food the locals usually can, so one of the first things they learn to say in a restaurant is "no pet," meaning "not hot".

Chili dipping sauce/condiment. Mind the seeds!

You'll likely get a small dish (a couple of tablespoons or so) of chili condiment with just about everything you order. There are lots of variations, but most have the four main Thai flavors in them: hot (chili), salty (salt and/or fish sauce), sour (pickled chili, lime vinegar) and sometimes sweet (sugar of one form or another). However you cut it a nice big spoonful will clear the sinuses   and tear ducts of most folks in short order. 

You shouldn't ignore the local foods wherever you go. That's what Pepto-Bismal, Immodium and electrolyte powders are made for. You live and learn, I figure, but use some common sense - such as asking a trusted expat or Thai friend when in doubt if you don't want to be very adventurous.

Most anything that's been cooked thoroughly and is kept hot enough isn't likely to bother you, and if it's something like raw produce you can read more in the post If You Can Peel It, You Can Eat It. 

Whether you feel more safe or prefer your Pad Thai in a restaurant, go for this:

Lunch at Chili Culture in Bangkok

If you're open to trying new things, you can go for the same dish as take away from any number of carts and stands...

At an open market

The point is: let common sense give you some direction, but don't let fear choose your path.