Yeast is added to certain foods like bread to leaven the bread, and others such as beer to cause fermentation. Actually, bread ferments too, but the alcohol evaporates during cooking.
Yeast is not usually added to foods that do not require a rising agent.
Pasta and noodles, including gluten-free pasta, Thai, Chinese or other Asian noodles are not made with added yeast. These are dense foods that would fall apart if yeast were added and the dough allowed to rise.
Although it is easy to predict that pasta is yeast-free, always check ingredients, just to be sure. You can never be sure quite what some food manufactures will add to their ingredients!
Yeast Overgrowth and Pasta
Pasta and noodles are high in carbohydrates. If you are worried about starving a yeast-overgrowth, you should avoid noodles and pasta and focus more on whole grains (I mean whole, not milled in any way, as in you can see the whole individual grains) and protein such as meat. The less processed the carbohydrate, the better.
Complex carbohydrates like pasta are only a step or two away from sugar, which feeds the yeast.