 Researchers have conducted studies in an attempt to see if such advertisements have effects on teenage body image, and what those effects might be.Researchers, such as Mary Martin and James Gentry, have found that teen advertising reduces teenagers' self-esteem by setting unrealistic expectations for them about their physical appearances through the use of idealized models.Other researchers, such as Heidi Posavac, acknowledge this, but believe that this only applies to teenagers who already possess low self-esteem or a poor self-image.