Aims: To analyze and quantify the sociodemographic, behavioral, and clinical factors influencing the oral pain and eating difficulties reported by Spanish 35- to 44-year-old adults and more elderly people in the most recent Spanish National Oral Health Survey. Methods: Pain and chewing difficulties were gathered in a Likert-scale format from a representative sample of the Spanish general population between the ages of 35 and 44 years (n = 540) and 65 to 74 years (n = 540). Risk factors were identified using bivariate analysis, after which the crude association between risk factors (sociodemographic, behavioral, and clinical) and outcome variables (pain and eating problems) was assessed by adjusted odds ratios, calculated by means of multivariate logistic regression. Results: In the 35- to 44-year-old adults, eating problems were mainly associated with caries and prosthetic treatment needs and oral pain by the number of decayed teeth. In the more elderly individuals, eating problems and oral pain were influenced by prosthetic needs and the number of missing teeth. Female sex was seen to be a risk factor for suffering pain and eating restrictions. Additionally, several independent variables such as social class, place of residence, brushing habits, or periodontal needs became nonsignificant after logistic regression modelling. Conclusion: According to this high-specificity regression model, caries and prosthetic treatment needs should be considered key factors in determining the oral well-being of the Spanish population. Missing teeth represent the most relevant influencing factor for the elderly and decayed teeth for younger adults. Keywords: eating difficulties, epidemiological studies, oral health-related quality of life, oral pain, self-assessment