Sunday, January 02, 2011

Unhealthy lifestyle 'ingrained by age 16'

The opening claim below is a counterfactual absurdity. If "obesity" etc. is "unhealthy", how come people of middling weight live the longest?

On a personal note, my lifestyle would be greeted with horror by the vastly opinionated do-gooders. I have done no exercise since I was 16 and have always had a sedentary lifestyle. I have always eaten whatever I fancied and I like a drink. Yet far from "a life of illness", all I have had were occasional colds and flu (about one a year) and I am still in good working order at age 67, though not everything works as well as it once did, as is to be expected at my age

Unhealthy lifestyle choices could be so ingrained in us by the time we are 16 that there is no way back from a life of illness, scientists claim. A sedentary lifestyle, bad eating habits and alcohol consumption all kick in by the age of 19, but researchers found that 16 was the 'tipping point' for this type of behaviour. And they recommend that children under 13 should be targetted for health campaigns before it is too late to change.

The findings were presented in a doctoral thesis submitted by Marta Arrue to the University of the Basque Country in Spain.

She said:"The least healthy habits turn out to be eating ones, followed by ingestion of alcohol, sedentarism, risks involving sexual relations, the consumption of tobacco and drugs and, finally, low quality or insufficient sleep.

"Special attention has to be paid to adolescents of 16 years. This is the point of no return, as it were, the age in which either healthy activities are opted for or risk behaviour patterns arise.

"The data point to the fact that young persons show more risk behaviour than expected, more even than they themselves perceive, believing that they are healthier than they really are.

"It is notable that risk behaviour presents itself in early adolescence and that all the habits, except sleep, worsen with the passing of the years."

Ms Arrue studied 2,018 young people from the Basque region who were asked to fill in various questionnaires. With the gathered data, she collated and analysed habits of life according to sex and age, adolescents from 13 to 17 and young persons from 18 to 26.

She added: "Bad eating habits, ingestion of alcohol and sedentary lifestyles are all unhealthy life habits that are already being detected in early adolescence and that are especially predominant amongst women and young people between the ages of 19 and 26.

"The prevention campaigns should take very much into consideration these groups at risk and even take into account those less than 13 years.

"Women show greater risk conduct than men. The weak point of women is sedentarism, tobacco, sleep, risk of becoming pregnant and sexually transmitted diseases. "Men, on the other hand, show weaknesses with alcohol, illegal drugs and eating.

"The results show that adolescents and young people with healthy life habits have higher self-esteem, better psychological wellbeing, greater satisfaction with their bodies and fewer psychopathological indicators.

"A tendency to bad habits is not due to lack of information, as has been borne out by the numerous campaigns undertaken, and so other factors must be involved."


Queensland scientist closes in on world breakthrough to beat killer disease

This is very hopeful news. Dengue is like a very severe flu

A QUEENSLAND scientist is on the brink of eliminating the deadly global disease threat of dengue fever after more than 15 years of painstaking research. The University of Queensland's Professor Scott O'Neill will start his world-first field trials to wipe out the mosquito-borne disease in far north Queensland this week.

The project, funded by the Bill & Melinda Gates Foundation's Global Health Program, hopes to control dengue by introducing a bacteria to mosquitoes that stops them passing on the virus to humans. The bacteria, known as Wolbachia, has a powerful ability to invade natural populations of insects and alter their reproduction and lifespan.

"I was always interested in science but I wanted to do science with a practical outcome," Prof O'Neill, 48, said. "This is very exciting for me and my team - we can provide a real solution to the global burden of disease."

Dengue is a significant disease that has no effective controls or vaccine - it affects billions world-wide and costs millions of dollars to treat. It is carried by an urban-dwelling mosquito that, once established in cities, is almost impossible to eradicate.

Dengue hot spot Brazil spends $US800 million a year on pesticides to control mosquitoes and still has one of the highest cases of infections in the world.

"The scary thing is dengue is getting worse, with a broadening geographic distribution and outbreaks becoming more severe," Prof O'Neill said. "We can see that in our own experience in Australia." There were more than 1000 cases of dengue in Queensland in 2009 - the worst outbreak in 50 years.

But discovering the effect Wolbachia has on the dengue-carrying Aedes aegypti mosquito did not happen in a "lightbulb moment" - it has taken decades.

"When you are doing scientific work more experiments fail than succeed, so you keep chipping away to find ways around the problem," Prof O'Neill said. "I think it's a sickness that a lot of scientists have - they are very obsessive people and that's what makes them so tenacious about their projects."

One member of the Eliminate Dengue team was once required to manually inject 10,000 mosquito embryos with the bacteria to test their survival.

Prof O'Neill was first alerted to Wolbachia by former UQ professor Hugh Patterson when he was Patterson's student in the 1980s. Scientists had been thinking about the bacteria as a way of controlling insect populations but Prof O'Neill wanted to test its ability to prevent disease transmission.

Leaving Brisbane for the US, he kept up his investigations as a junior professor at Yale University for 10 years. Returning to UQ as head of the School of Biological Sciences, his team was the first to apply molecular biology to the bacteria sequencing the Wolbachia genome.

"Dengue is spread by old mosquitoes (12 days old)," he said. "I thought if we could shorten their lifespan we could stop transmission of the disease. "It not only shortened their lifespan but it interfered with the virus's ability to grow in the insect. "That was quite an amazing discovery and it means this approach can be much more effective."

This week Prof O'Neill's team will begin releasing Wolbachia-infected mosquitoes into the wild population.

The CSIRO has done a nine-month risk analysis on releasing Wolbachia mosquitoes into the general population to breed. Prof O'Neill said this type of science was heavily regulated in Australia and they were being extremely careful because they did not want to create another biological problem like the cane toad.

"The cane toad was a foreign organism introduced into a new environment but Wolbachia already occurs naturally in up to 60 per cent of the insect population," he said.

In September the Australia Pesticides and Veterinary Medicines Authority gave the project approval to proceed to field trials at Yorkeys Knob and Gordonvale near Cairns.

Over the past 15 years, the international collaboration has involved more than 14 institutions and 50 scientists from Australia, Vietnam, Thailand, the US and Brazil.


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