To assess the clinical efficacy of a novel organic olive oil-based denture adhesive and its effect on Candida Albicans growth in maxillary edentulous individuals wearing complete dentures. Individuals were selected from two Dental Schools in Portugal and Spain. Twenty-eight complete dentures were relined, following a standardized protocol. The novel product (Test) was compared with a commercialized adhesive (Control) and Vaseline (Placebo) randomly assigned in a cross-study design. The retention resistance was measured with a Gnathometer and a dynamometer, the patient related outcome evaluations with a 5-points questionnaire and the Candida albicans growth in a Sabouraud dextrose agar (SDA) medium in order to evaluate differences between the placebo and experimental product. Twenty-three participants were included. Dynamometer evaluation showed significant differences between not using a denture adhesive and using either (experimental, p = .03; control, p = .04), no significant differences between the two adhesives (p > .05). In the subjective analysis, the experimental adhesive showed a significantly longer effectiveness (p = .001); the control reported better results at taste (p = .03) in chewing (p = .001). The test adhesive showed better (p < .001) Candida albicans growth inhibition. The experimental adhesive showed longer effectiveness than the control and placebo with a better inhibition capacity for the growth of Candida albicans, patients reported better abilities for speech, chewing, taste and retirement in the control adhesive.