A Philadelphia roll, also sometimes called a Philly roll or a salmon skin roll, is a type of sushi roll that typically contains smoked salmon, cream cheese, and cucumber. While the ingredients in a Philadelphia roll are generally considered to be healthy, the overall healthfulness of the dish depends on how it is prepared. For instance, if the salmon used in the dish is high in mercury, it could potentially negated any health benefits from other ingredients. Additionally, some sushi restaurants may use less-than-fresh fish or may not follow proper food safety guidelines when preparing their rolls, which could also make them less healthy. In general, however, a Philadelphia roll made with fresh ingredients and properly prepared should be a relatively healthy option.