Body image is one of the most primary issues that are faced by women that participate in beauty pageants. This can be greatly exacerbated in the case of childhood participation in beauty pageants.
After a self-assessment study done by researchers Anna L. Wonderlich, Diann M. Ackard, and Judith B. Henderson and conducted at the University of Minnesota, results showed a significant association between childhood beauty pageant participation and body dissatisfaction, greater impulsive behaviors, as well as difficulties with trust in interpersonal relationships out of the adult women that participated in the study. The findings from this study suggest that participation in child beauty pageants may have a strong influence on body dissatisfaction and impulse regulation, however the study found that there was no significant evidence for bulimic behaviors or body perception.
They also concluded that since viewing media promoting an ideal body image of thinness and experiencing the pressure to embody this ideal during childhood beauty pageants are similar experiences, this level of exposure is likely to blame for the negative effects on mental health and the increase in body dissatisfaction.
That being said, this does not mean that they are at less of a risk for developing eating disorders. The beauty standard that is enforced within the beauty pageant scene can have negative effects on what women think they should look like and could potentially drive them into such a state that they fall into a harmful eating disorder. It is important to be aware of the things that normalized staples in society - like adult or child beauty pageants - are promoting and the messages they are sending to the women that watch and participate in them.
References
Wonderlich, A. L., Ackard, D. M., & Henderson, J. B. (2005). Childhood Beauty Pageant Contestants: Associations with Adult Disordered Eating and Mental Health. Eating Disorders, 13(3), 291-301. https://10.1080/10640260590932896