Are gadgets bad for our health?

Can mobile phones trigger cancer? Can your computer keyboard make you ill? Do videogames rot our brains? There are as many rumours and myths about how technology affects our health as there are shiny new gadgets to play with.

But how much truth is there behind the headlines? We found out what the experts have to say about whether technology really is bad for our health.

Can mobile phones trigger cancer?

The link between mobile phone usage and cancer has been debated for almost as long as we've had mobiles.

There is a large body of specialists who believe the two are interlinked. For instance, the International Agency on Cancer has listed mobile phones in 'group 2B' of its 'gold-standard' rating system - its way of saying handsets could 'possibly' cause cancer.

However, no firm evidence has ever been produced to suggest that mobiles can trigger cancerous growths.

In a study conducted by the Institute of Cancer Epidemiology in Denmark last year - in which 358,403 mobile phone owners were studied over an 18-year period - no evidence of mobile phone-induced cancer was found.

If you still have your doubts, Professor Magda Havas of the Institute for Health Studies at Trent University in Ontario, Canada, recommends chatting through speakerphone to reduce your body's exposure to radiation while using your phone.

She told CNN: "Hold it out two inches, and the radiation drops by a factor of four. Hold it out four inches, and it drops by a factor of 16."

Reality rating: 1/10

Could gadgets make men infertile?
Although no study has found a firm link between mobile phone usage and testicular cancer, a 2006 study conducted by US researchers and doctors in both the US and Mumbai, India, has found some evidence that suggests handsets can lower the quality and consistency of sperm.

Professor Ashok Agarwal of the Reproductive Research Centre in Ohio, who led the research, believes that electronic radiation produced by handsets is the root cause of the problem.

He told the Daily Mail: "Cells in the testes have been shown to be susceptible to electromagnetic waves in previous research in animals.

"Somehow electromagnetic waves may be causing direct damage to these cells and that perhaps causes a decrease in sperm production."

However, Dr Allan Pacey, a senior lecturer in andrology at the University of Sheffield, believes the study is flawed.
He told the BBC: "If you're using your phone for four hours a day, presumably it is out of your pocket for longer. That raises a big question: how is it that testicular damage is supposed to occur?
"If you are holding it up to your head to speak a lot, it makes no sense that it is having a direct effect on your testes."

Reality rating: 5/10

Is 3D to blame for my headaches?

With Hollywood pumping out floods of 3D movies, the 3D revolution is continuing apace.

However, in a study conducted by the University of California, Berkley, researchers have found that watching 3D movies could lead to both headaches and eyestrain.

Professor Martin Banks, who led the study, believes the trickery involved in 3D is to blame. He told the Daily Mail: "You converge and focus your eyes to the same distance.

"But with 3D, you may have to converge your eyes to one distance, while focusing to another. So with 3D films you're taking that normal relationship which has been in the brain for years and changing it."

Dr Michael Rosenberg at Northwestern University Feinberg School of Medicine in Chicago, says that those with eye problems are most at risk.

He told Reuters: "There are a lot of people walking around with very minor eye problems, for example a minor muscle imbalance, which under normal circumstances, the brain deals with naturally."

Rosenberg says 3D films require a greater deal of concentration than 2D movies. "That translates into greater mental effort, making it easier to get a headache," he said.

Reality rating: 4/10

Is the internet making me dumb?
The web is crammed with information but some experts believe it's doing our brains more harm than good.

Nicholas Carr, author of The Shallows: How the Internet Is Changing the Way We Think, Read and Remember, believes the internet is turning us into "scattered and superficial thinkers."

He wrote in the Daily Telegraph: "When we're constantly distracted and interrupted, as we tend to be when looking at the screens of our computers and mobile phones, our brains can't forge the strong and expansive neural connections that give distinctiveness and depth to our thinking. Our thoughts become disjointed, our memories weak."

However, in a 2010 survey in which 900 science, business and technology experts were questioned, it was concluded that the internet does actually make us smarter.

Janna Anderson of the Imagining the Internet Centre, who helped lead the study, said in a statement:

"Three out of four experts said our use of the internet enhances and augments human intelligence, and two-thirds said use of the internet has improved reading, writing, and rendering of knowledge."

Reality rating: 4/10

I'm ill - could my keyboard be to blame?

Computer keyboards can potentially harbour more germs than a toilet seat, according to a test conducted by the consumer group Which?

The company, which tested 33 of the keyboards in its offices, found that four were deemed health hazards - while another was so bacteria-ridden, it carried more germs than one of the toilet seats in the office bathroom.

Dr Wilson, a consultant microbiologist at University College London Hospital, said in an interview with Radio 5 Live that contagious illnesses such as a cold could be passed on through keyboards.

"If you look at what grows on computer keyboards, and hospitals are worse, believe it or not, it's more or less a reflection of what's in your nose and in your gut," he says. "Should somebody have a cold in your office, or even have gastroenteritis, you're very likely to pick it up from a keyboard."

Reality rating: 7/10

Are video games bad for our brain?
For years, video games have been blamed for turning us into zombie-like couch potatoes.

In a 2005 study led by the Criminological Institute of Hanover in Germany -
in which over 23,000 children aged between 10 to 15 took part - researchers concluded that prolonged exposure to video games leads to individuals becoming fatter, less active and less smart.

Christian Pfeifer, the director of the institute, told the Scotsman: "The results are truly alarming. Over-consumption of either makes them fat, lazy, stupid, ill, sad, unhealthy. TVs and computers literally steal meaningful time for play, sport and fun from their lives. In addition, brutal films or video games displace things learned at school or from parents from their memories."

However Nick Bilton, author of the book I Live in the Future and Here's How It Works, believes that there are several hidden benefits to playing video games.

He told Time magazine: "They are incredibly good for our brains. They increase hand-eye coordination, they increase working memory, and kids that play video games in a balanced way perform better on certain test scores."

Reality rating: 4/10

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