Saoirse Ronan's new role made her "more conscious" of her alcohol intake

She told The Sunday Times: "I'm more conscious of my intake - and there's more people of my generation who are choosing not to drink any more because of how it makes them feel."

The actress added alcoholism is a world she knows "really well" - admitting she has "been on the receiving end of the pain caused by it".

She also admitted she has seen people she loves "change because of addiction", adding: "There's a helplessness you feel when you watch someone you love - friends my age and one in particular who I'm close to... go through that.

"What will be etched in my brain forever is that switch, when the glaze goes over someone's eyes and they are gone.

"If you've become second best to alcohol you become resentful, so for this role I needed to put my own feeling towards it to one side.

"And I needed not to be angry about that any more."

Despite the pain she had witnessed due to the condition, Saoirse added alcoholism was a topic she "wanted to explore at some stage" in her life to better understand and heal her trauma related to it.

She said: "I don't think I would have been secure enough as a person to take something like that on even a few years ago."

Saoirse, who grew up in Co Carlow, Ireland, said children she knew would drink vodka or cider in a field because they were "bored".

'The Outrun' also stars Stephen Dillane, Saskia Reeves and Paapa Essiedu, with a synopsis for the movie - which is out in cinemas from 4 October - saying: "After living life on the edge in London, Rona attempts to come to terms with her troubled past.

"She returns to the wild beauty of Scotland's Orkney Islands - where she grew up - hoping to heal."