This paper explores the influence of the personality traits of dispositional optimism and risk orientation on Portuguese citizens’ preferences for lifestyle solidarity, on their lifestyle and the relationship between both personality traits. An online questionnaire was used to collect data from a sample of 584 Portuguese citizens. The quantitative analysis was performed through the Partial Least Square (PLS) model. The PLS explored the relationships between the constructs of dispositional optimism, risk preferences, own lifestyle and lifestyle solidarity. Linear regression analysis was also performed to identify the associations between respondents’ sociodemographic and economic characteristics and the above constructs. In general, respondents revealed high levels of lifestyle solidarity. Notwithstanding, we also found that: (i) while optimists and pessimists revealed less lifestyle solidarity, risk-prone revealed higher; (ii) while optimists were more prevention-orientation with their health behaviours, risk-seekers were less; (iii) more caregivers with their own lifestyles have less lifestyle solidarity, and (iv) while optimists were more risk-acceptant, pessimists were more risk-averse. This study presents the first evidence of how dispositional optimism and risk orientation affect the support of lifestyle solidarity and own lifestyles.