Here's a guy, on the letters page of the Times, who has the right idea (£):
Sir, I was excited to read... that eating mackerel will add two years to my life, because I'm a collector of added years. I added ten years when I stopped smoking, two when I gave up white sugar, three when I began eating bran for breakfast, six when I began going to the gym.
Anthony Calder-Smith - for he it is - hopes these added years will run consecutively rather than concurrently. I have a different worry. My ten added years for giving up smoking way way back - when do I get them? Or have I already had them?