To live to be 100 will not mean anything if a person is not happy with his life at present. The longevity to life means to live life to the fullest. Think for a moment what you want to achieve the most in life. How your life will change when you have everything you want. If you can enjoy every second of your life then you will certainly like to live longer and healthier. That is the real purpose of longevity that i can understand.A thread about longevity here makes me wonder about this. How long do you think is too long to live in this tiny planet? Does everyone here aim to reach 100 years of age?