by Karen Williamson

Life expectancy is rising steadily every year, with women living up to 79.9, on average, and men 75. Set your expectations higher with our guide to holding back the years.

Get laughing
A good laugh is like a mini-workout - 100 to 200 laughs are equivalent to ten minutes of jogging or rowing, says US cardiologist, Dr William Fry. Research also shows that it lowers levels of stress hormones, and heightens the activity of the body's natural defensive killer cells and antibodies.

Move to France
A report by the World Health Organisation found that the French outlive the British. They come third in the world rankings, compared to the UK at 14th. And better diet appears to be the deciding factor. French people tend to eat more fresh food, shop every day at local markets and rely less on convenience food than we do.

Go to bed later
Sleeping more than eight hours a night may reduce your life expectancy. A study in the Archives of General Psychiatry, US, found that people who get only six to seven hours sleep a night live longer. People who sleep eight hours or more, or less than four hours, a night were shown to have a significantly higher death rate.

Make your marriage work
Being happily married for a long time leads to greater life expectancy for men and women. However, divorcing then remarrying actually increases the risk of dying prematurely, says a study in Health Psychology Journal.

Walk, run, jump
Fit women have a 40 per cent less chance of developing coronary heart disease than those who don't exercise regularly, says Dr Ken Cooper of the Cooper Institute of Aerobic Research, US. He also found that people in the lower 20 per cent of fitness were three times more likely to die prematurely than the fittest group.

Have sex
Couples with a healthy sex life can look up to seven years younger than those who don't, according to a study by Dr David Weeks at the Royal Edinburgh Hospital. This is because sex reduces stress, leads to greater contentment and better sleep.

Live in the country
People living in rural areas have a higher life expectancy than those living in cities. Women living in west Somerset, for instance, live an average of 84 years, while those in Manchester live only 76, according to the Office for National Statistics. And a study from the Tokyo Medical and Dental School found that pensioners in cities who live near green open spaces tend to live much longer than those stuck in the concrete jungle.

Watch your weight
Overeating is one of the main causes of ageing and increases the risk of heart disease and cancers of the colon, womb, gall bladder, ovaries and breast. The British Heart Foundation says, coronary heart disease causes 270,000 heart attacks each year, and of these 28,000 are attributable to obesity.

Have lots of children
A study in Psychology of Ageing found that the more children women have, the greater their life expectancy. This could be because of the increased contact with and support from their children and grandchildren, as they get older.

Learn to play piano
Brain cells work together, so learning new skills improves your brain function generally. 'Whatever your age, ongoing mental stimulation will keep your brain building new spines on the dendrites of your brain cells,' says Dr Thomas Crook, author of The Memory Cure, (Thorsons, £9.99)

Look on the bright side
Researchers at the Mayo Clinic in the US found that optimistic people live about 12 years longer than pessimistic ones. Pessimists are more prone to viral illnesses, such as colds and flu. They are also less likely to carry out the essential self-examinations that detect breast or skin cancer, while positive thinkers are more likely to take health advice, say the researchers.