Middle aged men who would like to grow old in good health should have strong grip, not overweight, a good education, and a wife, according to a recent study.

A 40-year study of nearly 6000 Japanese-American men living in the US state of Hawaii revealed nine factors that were good predictors of which middle-aged men would live healthily into their 80s and beyond.

The nine factors were: not being overweight, low blood sugar levels, low levels of bad cholesterol, having low blood pressure, having a strong grip, not drinking alcohol excessively, not smoking, a high level of education and being married.

Upper body strength is indicated by grip strength which can be measured by a test. The study further proved, 'that it is important to be physically robust in midlife ... consistent with theories of aging that suggest that better built organisms last longer.'

The study began in 1965 when these men in the study were of an average of 54 years. It was found that those who managed to meet all the criteria of good health had an 80 per cent chance of living to age 80, in addition to having been more likely to attain old age while avoiding illness.

The results showed that 2451, of the 5820 original study participants, survived to age 85, with 655 participants having reached that age without suffering serious health problems such as heart disease, cancer, or diabetes.

Study author Dr Bradley Willcox of Pacific Health Research Institute in Honolulu, said, 'Your chances were more than 60 per cent of being healthy at that age if you avoided these risk factors, yet if you had six or more of these risk factors you had less than a 10 per cent chance of living into your mid-80s.'

The study pointed out that although the people in the over-85 age bracket is the fastest growing in industrialized countries, it also comprised the biggest consumers of health care resources.

In addition the study also showed a tendency of women to outlive men. Over twice as many American women compared to men live to age 85, while three times as many women were found to live into their nineties according to the report in this week's issue of the Journal of the American Medical Association.