The World Health Organisation (WHO) has predicted that depression will affect more people than any other health problem within the next 20 years.

Depression is set to place the biggest health burden on the economy for all societies as well as having a big social impact, according to the WHO yet developing countries spend less than 2% of national budgets on mental health.

Currently, 450 million people worldwide are affected by mental health disorders or disabilities and the majority of those live in developing countries.

A spokesperson for the WHO said depression is more common than widely feared disease such as cancer or HIV-AIDS. The increased burden will be on developing countries as they struggle to find resources to cope with mental health problems.

Figures published by the WHO show that 800,000 people commit suicide every year with 86% coming from low and middle income countries. Half of all mental health disorders begin before the age of 14 years-old.

The cost of treating mental health problems is an estimated £12bn per year which accounts for 1% of gross national product. The expectations is that this will increase significantly in the next two decades.

Depression is a disease that requires the correct advice and treatment just as much as any physical problem.