We examined relationships between drive for leanness and perceived media pressure to change appearance, internalization of an ideal physique, exercise frequency, and dieting. Men and women (N = 353) completed the Drive for Leanness Scale, the Sociocultural Attitudes Toward Appearance Questionnaire-3, the Eating Attitudes Test-26, and a demographic inventory. Drive for leanness was significantly correlated with athletic internalization (.52), pressure to attain an ideal physique (.25), exercise frequency (.36), and dieting (.25). Structural equation modeling revealed a good fitting model (χ2 = 2.85, p < .241; CFI = .99; NNFI = .98; RMSEA = .04; SRMR = .02) with internalization predicting drive for leanness, which in turn predicted dieting and exercise. Results reveal social/cultural theory helps enhance the understanding of the drive for leanness and its relationship with health-related behavior.