This study investigates the potential market demand and the effects of consuming senior-friendly foods on the nutritional status and quality of life of older adults in South Korea, which has rapidly become a super-aged society. Utilizing data from a 2024 field study, a Difference-in-Differences (DID) analysis was employed to evaluate the impact of senior-friendly food intake on calorie and nutrient supplementation, as well as improvements in quality of life. The findings reveal a substantial potential market, with 11.7 to 16.2% of individuals aged 75 and over expressing purchase intentions. Significant improvements were observed in both the Mini Nutritional Assessment (MNA-SF) and the Nutrition Quotient for Elderly (NQ-E) scores after the consumption of senior-friendly foods. Further, the intake increased daily calories by an average of 322.9 kcal, protein intake by 14.2 g, and fat intake by 12.1 g. The utility weight, indicating quality of life, also significantly increased by 0.037. Policy directions should prioritize promoting the senior-friendly food market to improve nutritional intake and quality of life among the rapidly growing older adult population, as evidenced by the significant positive effects observed in this study.