HOW TO LIVE LONGER: the three golden rules according to various research scientists: 1. Eating two portions of oily fish such as Mackerel a week extends lifespan by two years. 2. A diet that includes an ounce of walnuts twice a week can cut the risk of Diabetes by a qiarter. 3. Exercise brain and body together for at least an hour several times a week will stave off Dementia.