Yellow ingredient headings refer to ingredients that you should be cautious about. Some ingredients may be undesirable depending on the context and how high on the list of ingredients it is, which indicates its quantity in a food or treat. The ingredient may be lacking in studies to confirm safety, digestability or should be consumed in moderation (such as in a treat versus a food eaten daily in large quantities). In other cases, there may be other ingredients that are a better choice. Read their definitions carefully.