It is never too late to reap the benefits of a healthy, active lifestyle, research has concluded.
The benefits of regular exercise last well into old age
Scientists found 70-year-olds who take regular exercise, eat well, and do not smoke greatly increase their chance of living until 90.
The researchers estimate that longevity is only at most 30% down to our genes - the rest is down to lifestyle factors.
The study, by Boston's Brigham and Women's Hospital, appears in Archives of Internal Medicine.
ODDS OF LIVING TO 90
No risk factors: (Non-smoker, normal blood pressure, normal weight, no diabetes, regular exerciser): 54%
One risk factor:
Sedentary lifestyle: 44%
High blood pressure: 36%
Three risk factors (for instance, sedentary lifestyle, obesity and diabetes): 14%
All five risk factors: 4%
All odds for a 70-year-old man
The researchers tracked 2,357 male doctors whose average age was 72 when they joined the study in the early 1980s.
A total of 970 - 41% - lived to 90 or older.
Those who exercised two to four times per week, did not smoke, maintained normal body weight and blood pressure, and avoided diabetes had a 54% chance of living to 90.
In contrast, those who failed on each count had only a 4% chance of living to see their tenth decade.
Lead researcher Dr Laurel Yates said the findings were not surprising, but it was reassuring to discover that making the effort to stay fit and healthy still paid dividends in later life.
However, Dr Yates added: "Lifestyle changes are the hardest ones to make.
"It is a lot easier to take a pill. So the onus is on an individual."
Gordon Lishman, director general of Age Concern England said: "It's great that people are living longer, but it also means that many of us will face longer periods of ill health and disability in later life.
"In order to maintain both physical and mental health, we would urge older people to eat healthily and take regular exercise to stay fit and well."