In Katmandu, La Paz, and many other places, the only safe lettuce is boiled lettuce. Dishes containing meat are riskier than vegetarian foods, so becoming vegetarian when you travel will reduce stomach troubles. In most developing countries, fresh milk even milk that says it is pasteurized should be boiled before drinking. Yogurt is usually safe because the milk is boiled before fermentation and the final product is slightly acidic and thus less favorable for the survival of noxious bacteria. Sorbet tends to be acidic and, since acids are unfavorable to bacteria, this is a fairly safe food.
Ice cream is often risky in developing countries since power cuts make it difficult to store safely.
Ice, too, is ofen made with dirty water or handled with dirty hands. Sometimes it is delivered in huge blocks that are dumped onto the ground outside the drinks stall or hotel. Water that has been brought to a boil is safe enough, and boiling remains the best method of making contaminated water safe. Most weird foods will be safe to eat no matter how unaesthetic they may appear once they have been well cooked and are served hot. If you are in doubt about the safety of a new or weird food, ask locals about it, and do not overindulge yourself at first.