Worldwide, the number of old adults will peak in the coming decades. Relying solely on the chronological age to make treatment decisions and shape general or specific societal and medical considerations may reinforce ageism and lead to flawed reasoning. Defining physiological age using biological markers is not yet reliable, and an approach based on comorbidities without considering their impact on quality of life is inadequate. A multidimensional approach with strong integration of functionality is presented here to draw a real-world aging approach, easily accessible, clinically relevant, and of societal value.