In the United States we tend to either be offended by nothing or everything it seems. The only cultural taboos I could really think of are that it’s impolite to discuss a person’s weight, age or salary. Many cultures have certain things that are considered disrespectful or rude to do and these tend to differ among cultures. For example, in Afghanistan and other countries in the Middle East, it is extremely disrespectful to give the thumbs up sign, to sit with the soles of one’s feet/shoes pointing toward someone or to use the left hand to eat or pass dishes. These simple actions wouldn’t be given a second thought in the United States, but would be EXTREMELY offensive in certain other cultures!
Check out this video for more interesting examples of cultural taboos from around the world.