For most people, body satisfaction is crucial to develop both a positive self-concept and self-esteem, and therefore, it can influence mental health and well-being. This idea has been tested with younger people, but no studies explore whether body image interventions are useful when people age. This research validates a specific program designed for older people (IMAGINA Specific Body Image Program). This is done by employing a mixed experimental design, with between-subject and within-subject comparisons that focus on body satisfaction before and after experimental treatment, comparing two groups. Using this experimental methodology makes it possible to identify the effect of the intervention in a group of 176 people. The score obtained with the Body Shape Questionnaire (BSQ) was the dependent variable, and the IMAGINA program was the independent one. As for age, gender, relationship status, season, and residence environment, these were controlled variables. There were significant differences in body satisfaction between the two programs, obtaining better results with IMAGINA. The controlled variables had a much less significant effect than the treatment. Therefore, it is possible to improve body satisfaction in older adults through interventions similar to the one presented here.