What is healthy aging and longevity?How could diet affect healthy aging and longevity?Which supplements are of most interest for healthy aging and longevity?Separate from caloric restriction, can substantial restriction of carbohydrates (i.e., ketogenic diets) increase longevity by reducing insulin levels?What does healthy aging and longevity encompass?What are “biological clocks” and how are they used to measure healthy aging and longevity?