A study conducted in Japan explored perceptions of healthy life expectancy (HLE) among individuals with diseases and those without. Researchers administered an online questionnaire to 626 participants, including patients with colorectal cancer, individuals undergoing dialysis, and healthy individuals. The results revealed that patients undergoing dialysis were more likely to feel their health issues impacted their daily lives and were less inclined to credit their HLE to personal or family efforts compared to the cancer and healthy groups. Factors significantly associated with achieving HLE among those with diseases included being female, living with cohabitants, and having higher life satisfaction scores. The findings suggest that life satisfaction plays a crucial role in achieving HLE despite health challenges. Enhancing life satisfaction through social participation, support, and psychological interventions may contribute to extending healthy life expectancy among individuals with diseases.