Modern life is making us lonelier, and recent research indicates that this may be the next biggest public health issue on par with obesity and substance abuse. A recent review of studies indicates that loneliness increases mortality risk by 26%.

Loneliness is an increasing problem in modern life. The Church Urban Fund and the Church of England found a rise of 10 per cent in the last three years in clergy members who felt that social isolation was a major problem in their local area. Another survey by the Mental Health Foundation found that in the UK one in ten of us feels lonely often and 48 per cent of people think we are getting lonelier in general. Britain has even been voted the loneliness capital of Europe.

So why are we getting lonelier? Changes in modern society are considered to be the cause. We live in nuclear family units, often living large distances away from our extended family and friends, and our growing reliance on social technology rather than face to face interaction is thought to be making us feel more isolated. It means we feel less connected to others and our relationships are becoming more superficial and less rewarding.

We are social animals and need to feel that we "belong" to others and feel connected to one another. Social pain is as real a sensation for us as physical pain; researchers have shown that loneliness and rejection activates the same parts of the brain as physical pain.

Loneliness affects all of us at some point in our lives. Relocating to a new area, losing a loved one, and starting a course at university are all key times when people feel lonely. Research suggests that this experience of loneliness is useful to us as it motivates us to reconnect with others and to seek out new friendships to reduce the "social pain" that we feel. But for some, when reconnection is not easy or not possible, if a person is socially isolated, people can remain in this uncomfortable loneliness state for a number of years. Reports vary but typical numbers of people experiencing loneliness in this prolonged way range from three to 30 per cent.

For those that experience loneliness for a long time, research has shown that this impacts on their health in a greater way than smoking 15 cigarettes a day or being obese. Loneliness has also been linked to poor mental health. In a survey by Mental Health Foundation, more than a third of people surveyed had felt depressed as a result of feeling lonely.

There are a number of myths regarding who experiences loneliness. Certainly all of us feel it from time to time, but it is commonly known that loneliness particularly affects the elderly who may be socially isolated due to decreased mobility and loss of friends and partners. But it is not often acknowledged that loneliness also effects people at all ages, including children, and is particularly prevalent in the teenage years. Studies have shown that between 20 and 80 per cent of adolescents report feeling lonely often, which is compared to 40 to 50 per cent in an elderly population.

Another myth is that loneliness is typically associated with being alone, but it also effects people when they are surrounded by others and well-connected socially. This is because loneliness is about the quality rather than the quantity of relationships that we have, so a person may have a lot of friends but still find that their needs for social contact are not met.

What can we do to reduce loneliness? This question has not been an easy one for researchers to answer, as common sense approaches - such as increasing opportunities to make friends - do not always result in reducing a person's loneliness. Certainly where people feel lonely because they are social isolated, ways to reconnect, when found, can be used by the person to reduce their loneliness. In a recent study, loneliness was reduced in older people in residential care when they were given training in social media use so they could remain in contact with family and loved ones. But it seems that it is not as simple as this, because offering such opportunities does not uniformly reduce loneliness.

In a recent review, researchers found that strategies to reduce loneliness that target negative thought processes were the most successful. So it seems that for some lonely people, reducing social isolation and helping them link up with others reduces loneliness. But those who have been lonely for a number of years will have anxiety about making new friends, they may be distrustful of others and feel low about their own social skills. They need support to change their view of themselves, and how they feel others will react to them.