A total of 2,500 men in the 1979 HALCyon experiment were asked to eat well, take regular exercise, drink less alcohol, keep trim and never smoke.
Only 25 participants stuck to the health regime more than three decades later and they have dramatically cut their risk of cancers, diabetes, heart-attack, stroke and dementia. Their overall fitness was far better than the 2,475 pensioners that had given up on the experiment, part funded by Alzheimer's Society, and the development of heart disease was slowed by up to 12 years and dementia six years.
The volunteers, all from Caerphilly in Wales, gave researchers regular updates every five years on their diet and levels of recommended physical activity such as walking, cycling and sports.
