By Jill McGivering
World affairs correspondent, BBC News
In London, a team of leading health experts is calling for more resources for global mental health - and more recognition of the impact of mental illness on other health problems.
Mental health issues have a wide impact
The demand has emerged from a new special series of papers on global mental health launched on Tuesday by the medical journal, The Lancet.
Many of these experts in mental health sound frustrated.
They speak of mental illness as a neglected issue, especially in the developing world.
It is also marginalised and under-resourced, they say.
Mental illness accounts for about 14% of the burden of global disease - a calculation based both on premature death and years lost through disability.
That is a higher ranking than cancer and heart disease.
And yet those associated with mental health say it is a major battle to have their warnings taken seriously.
Competing for attention
Marjorie Wallace, executive director of the mental health charity, Sane, says mental health has really struggled to make it onto the global health agenda.
"Every time it seems to be that mental health is a luxury," she said.
"Competing against malaria, against HIV. People just don't taking account of the fact it's just as life threatening and just as distressing as these major other illnesses."
Mental illness is indeed life-threatening.
The team calculates that about 800,000 people commit suicide every year.
It is estimated than nine out of ten have a mental disorder in the period before they take their life.
And the burden isn┐t shared equally.
More than four out of five of the people who commit suicide are in low or middle income countries.
Mental health is a concern in itself - affecting quality of life, social relationships and the ability to be economically independent.
But the team is also keen to stress the impact of poor mental health on other physical conditions.
People who have mental health problems are more likely to develop other non-mental health problems.
The mental health issues may mean a increased risk of alcohol abuse, smoking and poor diet and physical fitness.
All of that could make them prone to heart disease, cancer, strokes or diabetes.
If they do develop a serious physical illness, they are also less likely to get the medical help, social support and treatment they need.
Their dependents may suffer too. There is evidence from India and Pakistan, for example, that mothers who are depressed are more likely to have a malnourished child.
Professor Jeffery Sachs is the special advisor to the UN secretary general on the Millennium Development Goals.
He is convinced by the arguments - but also cautious about the issue of resources - warning the team that their cry for help will be a marathon, not a sprint.
Many of those most in need of better mental health care have poor health systems and are already struggling to cope with other life-threatening diseases.
"Those countries, especially in Africa, simply can't afford the most basic life-saving health interventions," he told me, "like a bed-net to save them from malaria."
"The poorest countries will say: yes, we understand this, we know the burden of mental health in our communities, we know how pervasive the challenges of depression or schizophrenia or other mental health conditions are. But we can't afford it."
No-one wants to make choices between the value of bed-nets and anti-depressants.
The real solution, say the health professionals, is to increase the pie ┐ the amount of money being given to poorer countries for health.
But many of the experts are optimistic.
Basic mental health services can be provided cheaply and simply, they say, especially if they're made part of general healthcare, even delivered by non-specialist staff.