The old saying that “too much of a good thing can be bad for you” is true for many things. Some of the things that most of us take for granted and use simply as tools can become a compulsion for some people. The internet is a perfect example. While many use it for education, paying bills, and other things some can become addicted and replace the real world with the virtual.

There have been studies conducted on internet addiction before and one study conducted in 2009 found a link between internet addiction, ADHD, and aggression in teens. A teen in China in August of 2009 was sent to an internet addiction camp to be treated for addiction and was later beaten to death by counselors who though he wasn't trying hard enough in workouts.

A new study on internet addiction has been published by psychologists from Leeds University citing "striking" evidence that some internet users develop compulsive habits and replace real-world interaction with social networking and chat rooms reports Reuters. The study suggests that addictive surfing can have a serious impact on the mental health of users.

The study's lead author, Dr. Catriona Morrison, said, "The internet now plays a huge part in modern life, but its benefits are accompanied by a darker side. While many of us use the internet to pay bills, shop and send emails, there is a small subset of the population who find it hard to control how much time they spend online, to the point where it interferes with their daily activities."

According to the study, these internet addicts spend much more time visiting websites that are sexually gratifying, online gaming sites, and online communities. Users spending more time browsing sites of those types were more likely to have moderate to severe depression.

Morrison said, "Our research indicates that excessive internet use is associated with depression, but what we don't know is which comes first – are depressed people drawn to the internet or does the internet cause depression? What is clear is that for a small subset of people, excessive use of the internet could be a warning signal for depressive tendencies."

This study is cited as the first large-scale study of Western young people to probe the relationship between internet addiction and depression. The study evaluated the internet use and depression levels of 1,319 British people from 16 to 51 years of age. Of the users in the study, 1.2% were classified as being internet addicted. The study determined that young people are more likely to become internet addicted than the middle-aged users with an average age for the addicted group at 21 years.

"This study reinforces the public speculation that over-engaging in websites that serve to replace normal social function might be linked to psychological disorders like depression and addiction," added Dr. Morrison. "We now need to consider the wider societal implications of this relationship and establish clearly the effects of excessive internet use on mental health."