I am 76. A year ago I set a goal to live to be 100. My granddaughter is 1.5 YO and I want to see her finish college. Got the idea from Peter Atilla (Peter Attia (peterattiamd.com) I am lucky to be in excellent health and condition. 5 days/wk gym, resistance work and some cardio. I limit carbs to 100 g per day (inflammation, fat), use diet and protein powder to maintain muscle (sarcopenia avoidance), many sup's but esp NMN, resveratrol (per David Sinclair), teach two classes at local comm. college (keeps me reading, associating w younger crowd), no TV/soc media to speak of, avoid older people :) and seek out younger; work on balance using bosu ball; grip strength, leg strength exercises. finally, highly suggest reading stoic philosophy (related to "hope" in main article). finally, I spent 5-6 years learning about and improving sleep--maybe the most important. btw-best dietary source of melatonin is pistachio nuts. use only olive oil, blue berries once per day.