by splitting 251 female students into 4 letter-writing conditions: neutral letter, letter focused on body functionality, self-compassionate, or body-compassionate.
Participants in both compassionate as well as in the body-functionality letters reported a greater body satisfaction as measured, by the 6-item Body Image States Scale, which assesses how the subject feels in the present moment regarding physical appearance, body shape and size, weight, and physical attractiveness. The effect reached a maximum of 20%.
The exercise also had a 10% positive impact on positive affect.
Source: Stern and Engeln (2018)