People with poor literacy are more likely to suffer with mental health issues such as anxiety and depression, the first study to look at the global picture of literacy and mental health has found.

Some 14% of the world’s population currently has little or no literacy and women are disproportionately affected, accounting for around two-thirds of these.

According to Dr Bonnie Teague from the University of East Anglia in the UK, it is already known that people with better literacy tend to have better social outcomes when it comes to things like finding employment and being able to afford better food and housing.

“Not being able to read or write holds a person back throughout their life and they often become trapped in poverty or are more likely to commit crime. We also know that lower literacy is related to poorer health, chronic diseases and shorter life expectancy,” she noted.

While there has been some research examining potential links between literacy and mental health, this is the first study to assess this on a global scale.

The researchers reviewed data from 19 studies that measured literacy and mental health in almost two million people living in nine countries, including the US, China, India and Brazil.

They found a “significant association between literacy and mental health outcomes across multiple countries”, according to Dr Lucy Hunn of the University of East Anglia.

“People with lower literacy had greater mental health difficulties such as anxiety and depression. We can’t say for sure that poor literacy causes poor mental health, but there is a strong association.

“There may be multiple factors impacting on mental health which also impact literacy, such as poverty or living in an area with a history of conflict. However, what the data does show is that even in these places, you still see worse mental health for those without literacy skills,” she explained.

The researchers said that these findings highlight the importance of mental health services being aware of and supporting literacy.

The study is published in the journal Mental Health and Social Inclusion.