One in five people are thought to be affected by depression at some point in their lives.

Over 31 million prescriptions were written for antidepressants last year in the UK - a 6 per cent rise since 2005.

Selective Serotonin Reuptake Inhibitors (SSRIs) – which include Seroxat and Prozac - are the most commonly prescribed antidepressants. SSRI use increased by ten percent last year. They prolong the effect of the mood-boosting chemical serotonin, by letting it linger in the body.

Depression costs the UK 9 billion a year in treatment, benefits and lost revenue.

SSRI effectiveness is disputed – a big cheese at drug company GlaxoSmithKline admitted that “a majority of drugs only work in 30 to 50 percent of people.”

One in ten UK youngsters (aged 5-16) has a mental disorder – nearly one in twenty has anxiety or depression. Boys are more likely to suffer than girls.

Between 1992 and 2001, prescriptions of SSRIs for under-18s increased ten-fold.

The National Institute for Health and Clinical Excellence (NICE) – the body that recommends what doctors should and shouldn't prescribe – said that SSRIs shouldn't be used as a first-stop remedy for mild to moderate depression.

93 percent of GPs prescribe antidepressants because of a lack of alternatives, according to the mental health charity Mind.

One in five mothers may suffer from post-natal depression, according to a recent survey from The Royal College of Midwives.

Prozac is the world's most popular antidepressant, with 54 million users.

Despite our depression-addled age, the UK suicide rate is at it's lowest since records began – 8.5 deaths per 100,000.

One in seven UK adults has considered suicide at some point in their lives.

Anxiety and depression is the most common form of mental illness in the UK – affecting 9.2 percent of adults. Women are affected more than men – 11.2 percent compared to 7.2 percent.

Irish-born people have higher rates of suicide than any other ethnic group in the UK.

Black men have the highest rate of admissions into psychiatric hospitals.

Depression and anxiety account for one third of all work days lost to ill health.

The sales of self-help books on Amazon rose by 40 percent last year.

Around 20 percent of a GP's time is taken up by mental health problems.

The most common causes of depression are work and relationships.

Suicide is the commonest cause of death in men under 35.

Women are more likely than men to have multiple episodes of depression.

85 per cent of people who have tried a complementary therapy for depression found them helpful, according to the Mental Health Foundation.

Even dogs get the blues – Reconcile is a newly launched beef-flavoured antidepressant for pooches.

In a recent study, 90 percent of depression sufferers said that a 30 minute walk in the park boosted their self-esteem.

The World Health Organization predicts that depression will be the second largest single cause of ill health by 2020.

Almost 80 percent of people in the UK have at least 2 friends who have experienced mental illness.

No longer a career-killing taboo – stars who have been open about their mental illness include Johnny Depp, gardening guru Monty Don, Stephen Fry and Robbie Williams.

4% of those with depression and anxiety disorders received psychological therapy in the past year.

Experts say the cost of therapy is about £750 for each patient. The benefits to the economy (less time off work etc.) would be £1,880.

Private counselling sessions cost around £40 an hour.

More than 90 percent of primary care trusts have waiting lists of over a year for cognitive behavioural therapy. Experts say we need 10,000 extra NHS therapists.

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