More than half of the babies now in the UK and other rich countries are born to live up to 100 years, researchers say.

The Lancet study, published in the journal, said over the years have spent less severe disability.

Data from more than 30 developed countries shows that since 1950 the probability of survival has doubled the past 80 years for both sexes.

One expert said healthy behaviors for all age groups, the key is to enjoy, to live a long life.

Professor Kaare Christensen, the Danish Research Center on Aging at the University of Southern Denmark, who led the study, said the life expectancy has risen steadily since 1840, and there were no signs of this slowdown.

He said: "The linear increase in life expectancy does not mean a record of more than 165 years, a limit to human life-threatening.

"If life expectancy is approaching a limit, would probably be a delayed.

In 1950, the probability of survival between 80 and 90, on average, 15 to 16% for women and 12% for men.

In 2002 these figures had risen to 37% for women and 25% for men.

The study points out that until the 1920s contributed to improved child survival and childhood most to the increase in life expectancy.

Since then have been increased by advances in the survival of older men who nurtured since particularly evident since the 1970s.

Four times, "the people"

The researchers said that the man could now than with four stages of life - child, adolescent, young and old are considered old age.

She said there was no evidence that age group were less healthy than their younger counterparts, partly because the most vulnerable people first died, with the strongest survive in the past 85th

Danish research has shown that almost 30% to 40% of individuals between the ages of 92 unrelated to the 100th

And a study of super-centenarians in the United States of America (in old age from 110 to 119 years) shows that even at this advanced age, 40% needed help or are independent.

Professor Christensen said that the United Kingdom and other countries caused the detection of a deferral limitations and disability caused by illness, despite an increase in chronic diseases.

This increase is explained by better diagnosis and treatment of diseases such as heart disease and cancer.

He said: "A growing number of elderly and very old time is a major challenge for health systems represent.

"Evidence now, however, suggests that people not only live longer than before, but they also live longer with fewer disabilities and less functional limitations."

Some researchers have be noted that the growth rates of obesity, the lifespan is limited - but Professor Christensen said that such predictions were too short.

He said: "Life is a lottery, and some overweight people live on a 100 and some thin people who do not die early."

Professor Alan Maryon-Davis, president of the Faculty of Public Health, said that after there are still concerns that were obesity and unhealthy behaviors many people's lives should be shortened.

He said: "It's great that as a nation, we are living longer and staying young - but we will do what we have for those who have it harder, can help lead a healthy life."

The Ministry of Health said that the increased life expectancy would be an impact on the future funding of care in England have.

A spokesman said it would examine the results of the study.

"We know that our society is evolving ... We want to ensure that people are living longer enjoy, continue on a good quality of life. In 2040 we expect 1.7 million more adults to nursing care.

"We want to be able to really good care for all who enter it must have, then we radically the way the system is financed to change.

Free plans for a national service and support at home for the elderly provide support need it most, was authorized by the Prime Minister of the Labor Party conference announced.