Laugh and the world really does laugh with you, say scientists

IT'S official: happiness really is contagious. The sought-after commodity "ripples" through social networks, creating clusters of contentment and transferring the "feel good" factor for up to a year, according to a study released today.

The findings are seen as the first tentative evidence of the concept of karma, suggesting that the "waves of happiness we radiate could eventually wash up on our own shores".

Unsurprisingly, happy smiley people tend to be at the centre of social networks and have lots of friends who are also happy.

But those with a Victor Meldrew disposition need not despair, because even a complete stranger can boost your happiness quotient.

A happy friend of a friend of a friend increases the chance of personal happiness by about 6 per cent. Grumpy friends, on the other hand, decrease it by about 7 per cent. Co-workers have no effect.

However, the optimum happiness generator is having a friend living within half a mile, which boosts your wellbeing by an impressive 42 per cent. A happy next-door neighbour ups the odds of personal happiness by 34 per cent, while a sibling living within a mile increases your total by 14 per cent.

The research, carried out by Professor Nicholas Christakis from Harvard Medical School and Professor James Fowler from the University of California, San Diego, found an individual's happiness depends on the mood of close friends, relatives and neighbours.

The research, published in the British Medical Journal, found a person's proximity to happy people could be significantly boosted by living with a happy partner or near a happy friend.

The findings suggest that clusters of cheerfulness are caused by the spread of happiness, rather than people choosing to associate with happy people.

The authors said: "Changes in individual happiness can ripple through social networks and generate large-scale structure in the network, giving rise to clusters of happy and unhappy individuals.

"Most important from our perspective is the recognition that people are embedded in social networks and that the health and wellbeing of one person affects the health and wellbeing of others.

"Human happiness is not merely the province of isolated individuals."

The study was based on data collected in the Framingham Heart Study between 1971 and 2003, involving 5,124 adults aged from 21 to 70.

Dr Cliff Arnall, a psychotherapist in happiness and confidence, said the research reminded people to look after their mental health. "It is giving them permission to say if someone is making them feel bad and telling them what to do about it.

"Certainly the happiest people I've met actually seek out happy people. If they realise they are in the presence of energy-sapping people, they move away, treating unhappiness almost as a contagious disease."

Being happy can also bring health benefits. Andrew Steptoe, a professor of psychology at University College London, said: "Happiness has a protective effect on your immune system and you produce fewer stress hormones."

FACT BOX

How to be happy:

• Think and act happy, this creates a positive state of mind for yourself and others.

• Surround yourself with happy people and nurture those relationships.

• Set realistic goals which move you forward step-by-step.

• Stay open to new people and experiences so that you continue to grow.

• Seek out and make time for activities which absorb you.

• Read this terrible joke before you turn the page: What do you call an elf who falls into a cement mixer? A wee hard man.