Background Understanding how people manage everyday health challenges is vital for developing self-care policies that are inclusive, equitable and effective. Little is known about how demographic characteristics shape self-care confidence, symptom management strategies and health-seeking behaviours across the UK adult population.   Objective The aim of this study was to examine the demographic predictors of self-care engagement among UK adults, focusing on self-care confidence, health information-seeking behaviours, symptom management strategies and perceived barriers to self-care.   Methods A cross-sectional online survey collected data from 3,255 UK adults, including a subset of health and care professionals (HCPs) to assess self-care knowledge, confidence, practices and health information accessibility. Ordinal logistic regression was used to identify demographic predictors of self-care engagement.   Results Regression analyses highlighted marked demographic disparities in self-care engagement. Older adults (65+) were significantly more confident in their self-care knowledge (aOR=3.22) and healthy lifestyle behaviours (aOR=2.96) yet were also more likely to seek health information. Males reported lower self-care confidence than females (aOR=0.79). Black British participants were more confident in self-care knowledge (aOR=1.99), but along with Asian British individuals, were significantly less likely to seek health information (aORs=0.56 and 0.70 respectively). People living with disabilities (aOR=0.69) and long-term conditions (aOR=0.76) reported lower confidence across self-care domains. HCPs consistently reported higher self-care confidence (aOR=1.51, p=0.006) and health behaviour engagement (aOR=1.66). Financial constraints (53%), lack of time (47%) and low self-efficacy (22%) emerged as key barriers to self-care, alongside low use of pharmacists (1.3%) and digital resources (9.7%).   Conclusion This study highlights demographic disparities in self-care confidence, information-seeking behaviours and barriers to engagement, urging the need for tailored self-care interventions. Future research should explore interventions to improve health literacy, enhance pharmacist-led self-care support and promote equitable access to digital health resources are essential for optimizing self-care engagement across diverse population groups.

The authors have declared no competing interest.

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The study was reviewed and given ethical approval by Imperial College Research Ethics Committee (ICREC #6979141). Participants consented to take part in the survey.

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