The danger: The primary cause for concern with sushi is the presence of parasites—tapeworms, flatworms and roundworms, for example—in the raw fish. To minimize risk, eat sashimi (sushi made with raw fish) at restaurants where the chefs not only know how to purchase the best fish, but also know how to identify and remove parasites during preparation. While no raw fish can be guaranteed safe, dipping it in soy sauce and wasabi may have a mildly antimicrobial effect.