There's mounting evidence that Facebooking, Twittering, and other "social networking" activities can kill you.

A study (PDF) published in Biologist, the journal of the British Institute of Biology, details how face-to-face contacts with friends and family are being replaced by face-to-screen isolation, and how the lack of real-world social interaction can increase your susceptibility to cancer, dementia, heart disease, diabetes, influenza, rheumatoid arthritis, lupus - even the common cold.

In "Well connected? The biological implications of 'social networking'," Dr. Aric Sigman, a Fellow of the Royal Society of Medicine, cites studies showing that social networking use in the UK is now the highest in Europe and that the isolation it causes can lead to measurable physical changes - destructive measurable physical changes.

The culprit is solitude. "Couples," writes Sigman, "now spend less time in one another’s company and more time at work, commuting, or in the same house but in separate rooms using different electronic media devices."

He reports that social scientists have determined that over the last two decades, "the number of people saying there is no one with whom they discuss important matters nearly tripled." The number of both kin and non-kin confidants is "dramatically smaller."

The average Briton, Sigman reports, now spends only about 50 minutes per day "interacting socially with other people."

We're also raising a generation of socially isolated kids. "Children now spend more time in the family home alone in front of TV/computer screens than doing anything else," he writes. The good doctor also cites a study that "reports that 25 per cent of British five-year olds own a computer or laptop of their own."

Aside from the fact that the art of intelligent conversation is being lost, Sigman says that digitally induced solitude has nasty physical implications. "Social connection, both objective and subjective, is increasingly associated with physiological changes known to influence morbidity and mortality," he writes.

Social isolation, for example, has been shown to impair the genes involved in the development of leukocytes, those helpful cells that float around in your blood, fighting disease.

Other studies have proven that social isolation reduces the effectiveness of tumor-fighting cytokines. Sigman cites a number of studies that have shown that socially active women with breast and ovarian cancer produce more and more-effective tumor-fighters, including the charmingly named Natural Killer cells.

Isolation can induce loneliness, which Sigman says has been linked to "low-grade peripheral inflammation." And that, he says, has been linked to inflammatory diseases such as diabetes, cardiovascular disease, and autoimmune disorders.

"Lack of social connection or loneliness is also associated with increased risk of cardiovascular disease," he continues, citing studies that link the production of the heart-healthy neuropeptide oxytocin to "hugging" and "touch."

It gets worse. Women with fewer social relationships experience strokes at more than twice the rate of those with more social relationships, and those with smaller social networks have narrower arteries - approximately one-third narrower, to be specific.

Real-world friendships help prevent heart attacks.

Sigman identifies the villain in this health-destroying isolation. Over ten years ago, a study of 73 internet-using families dubbed Internet Paradox (PDF) argued that the net decreases real-world communication while increasing depression and loneliness.

Internet Paradox has been the subject of some debate since its release in 1998, but its closing words are hard to argue with: "People should moderate how much they use the Internet and monitor the uses to which they put it."

In other words, skip that next Tweet, postpone polishing your LinkedIn profile, put off updating your Facebook status, and go hug someone.

You'll live longer. ®

Fakebook and Liespace are the worst things that have ever happened, thankfully I am not on either or any so called socail network sites, but so many activists are, I like the revoluntionary idea of meeting people face to face and discovering friendships in a more personal way.