Sexual objectification is the treatment of a person as a body or a collection of body parts that are valued primarily for their sexual appeal. The main purpose of this study was to determine the relevance of sexual objectification to women's health and well-being across the life cycle, from middle adolescence to old age. Additionally, the relevance of age and education to sexual objectification and its association with traditional gender role attitudes was examined. The study was cross-sectional and the sample consisted of 6,112 Spanish women between the ages of 16 and 85, who were assessed using seven questionnaires and scales. The results showed that lower age and lower number of children were associated with greater importance of sexual and physical attractiveness and with a more sexualized image, although there were no differences between adolescent and emerging adult women. Greater importance placed on sexual and physical attractiveness, as well as total sexual objectification, was associated with greater mental distress, lower psychological well-being, lower life satisfaction, and lower self-esteem at every life stage. Greater importance placed on sexual and physical attractiveness was associated with more traditional gender role attitudes among all age groups, except for older women. We conclude that sexual objectification is a threat to women's mental health and well-being.