There are concerns that social networking keeps people apart
People's health could be harmed by social networking sites because they reduce levels of face-to-face contact, an expert claims.
Dr Aric Sigman says websites such as Facebook set out to enrich social lives, but end up keeping people apart.
Dr Sigman makes his warning in Biologist, the journal of the Institute of Biology.
A lack of "real" social networking, involving personal interaction, may have biological effects, he suggests.
He also says that evidence suggests that a lack of face-to-face networking could alter the way genes work, upset immune responses, hormone levels, the function of arteries, and influence mental performance.
This, he claims, could increase the risk of health problems as serious as cancer, strokes, heart disease, and dementia.
Dr Sigman maintains that social networking sites have played a significant role in making people become more isolated.
"Social networking is the internet's biggest growth area, particular among young children," he said.
"Social networking sites should allow us to embellish our social lives, but what we find is very different. The tail is wagging the dog. These are not tools that enhance, they are tools that displace."
Dr Sigman says that there is research that suggests the number of hours people spend interacting face-to-face has fallen dramatically since 1987, as the use of electronic media has increased.
And he claims that interacting "in person" has an effect on the body that is not seen when e-mails are written.
"When we are 'really' with people different things happen," he said.
"It's probably an evolutionary mechanism that recognises the benefits of us being together geographically.
"Much of it isn't understood, but there does seem to be a difference between 'real presence' and the virtual variety."
Dr Sigman also argues using electronic media undermines people's social skills and their ability to read body language.
"One of the most pronounced changes in the daily habits of British citizens is a reduction in the number of minutes per day that they interact with another human being," he said.
"In less than two decades, the number of people saying there is no-one with whom they discuss important matters nearly tripled."
Dr Sigman says he is "worried about where this is all leading".
He added: "It's not that I'm old fashioned in terms of new technology, but the purpose of any new technology should be to provide a tool that enhances our lives."
A selection of your comments to the BBC news website:
I agree that I would prefer face to face contact with my friends and family, but as an immigrant to the UK who is separated from so many friends and family far away in another country and as a disabled person with a variable health condition that means that some days I am unable to get out of bed, the internet and social networking is a real life-line for me. Losing track of old friends can happen so easily. I've re-established many friendships this way. Morgan, Wales
Just a week ago I switched off my Facebook account for just this reason. These sites claim greater social networking, but all it really creates are more distractions for people, more isolation in front of their computers, more escapism, and a false sense of relationships with other people. People do not interact with each other properly, becoming more isolated and so more depressed. Travis, Bochum, Germany
I don't see this at all. For me, and I think a lot of people with Aspergers and other ADS's, these sites make it easier to meet people. If anything you are meeting people who you might never have spoken to without meeting them online first.Chris, Medway, Kent
I can agree with some of this, if you are communicating with your neighbour by facebook then that is a problem. I live in Norway but I come from New Zealand, with facebook I can really be a part of my friends' and family's lives. I think it's great, but in moderation.Simon, Norway
I live in a very rural community that unfortunately is seriously lacking in community spirit. There is very, very little to do and very little social interaction. I do not drive and I am home with small children. If it weren't for Facebook I would feel even more isolated from society than I already am. Facebook reminds me that there are people out there who care about me, even though they may be people I grew up with that live thousands of miles away. Elizabeth, Shetland
I am a full-time wheelchair user and use social networking sites as it is not so easy for me to get out and meet people. However, I do agree with Dr Sigman and I am often aware of the need to get out and meet people rather than just type away to whoever chooses to read. I also think the quality of communication is affected; it's all gossip and silly comments, hardly anything of substance. Much better talking to a good friend in confidence, in private, face to face. It's more productive and in the long run more meaningful and good for well-being. Rachel Ellis, Warrington, Cheshire, UK
I use most of the social networking sites that there are. I live in a small village where nobody talks to each other in person. I've tried everything to create human interaction and even done a School for Social Entrepreneurs Course to assist me in that but to no avail. I know that online friends are not the same but I am a single parent and not working. It is the only social interaction I can get to drive away the loneliness. When people are not online I miss them. Shona, Kirkcaldy, Fife
I couldn't agree more. I witness my 4 year old son and his 8 year old sister interact wonderfully when playing together, yet they become 'withdrawn' and subdued when playing solitary electronic games. Technology should enhance the human experience, but often fails to live up to its brief and actually causes more harm compared to when we did without. Mark E, Corby, Northamptonshire
I'm fed up with the number of people telling me I should join facebook. I have an active social life, I use phone and email to keep in touch and just can't see the point of it all. If I want to keep in touch with friends I will, if I don't I won't so the argument that you can catch up with people that you haven't seen for years is irrelevant to me. I even have a couple of friends who only send invites to their parties through facebook! I'm not a traditionalist at all, in fact quite the opposite, I just think the social networking fad is all a bit sad, I'd rather to go out and have fun with real people. Andrew, London
I used to use Facebook quite a lot. I had a lot of 'friends' on there. These were people who I knew 'in real life' and didn't get a chance to see and speak to regularly, others were people I knew only in passing or as an acquaintance of other friends. I am not a social butterfly and I find making friends very difficult. But after some time I realised that I was spending more and more time altering my 'status' and logging into Facebook, than I was spending with actual real-life friends. I think the report cited is absolutely correct and there is an issue of people becoming distant from human contact. I think it is right that scientists are concerned about us becoming isolated from other human beings. I deactivated my Facebook account because I realised I was spending a lot of time with it which could be better spent elsewhere. C.A.D, UK
These health effects seems pretty far fetched to me. I am a retired teacher who loves Facebook. Surprisingly, I have been in contact with former students I had forty years ago. It is a wonderful tool. The health benefits to me have been wonderful. I am grateful for such services. Who would have ever thought so many former students would stop by my site and say hello?Richard Orndorff, Mason, Ohio, USA
I think it brings people together, in a sense that I communicate with people I wouldn't even be interested to in real life. I have managed to get invites to social functions more than I did before. My social scene has in actual fact improved.Martha, Johannesburg SouthAfrica
The very best friends I have ever had in my life, I met online and this was before the social networking sites came to be. I've travelled to visit them and attended one of their weddings. Anything that helps people make friends is good and not harmful in my opinion. Mark Townsend, Cambridge, UK
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