In an interview on BBC Radio 4's Desert Island Discs set to air today, the 89-year-old said that her work is the key to her longevity and retirement was a killer for older people.
"I can be feeling like death warmed up when I come in, and then I'm alive. It keeps me alive," she explained.
She went on the say: "I think that's why a lot of people are very lonely and get ill when they're older, because I think loneliness and having no motivation, nothing to work towards … I think it kills you."
June said that she had no plans to quit from the show, which she has been a part of for 32 years.
The actress, who has portrayed laundrette worker Dot Branning for over 30 years, was also asked about how she kept her energy levels up for acting.
June said: "I haven't really got very much now but I find when I get on set, my energy comes.
"It's like people can go on stage and break an ankle and they don't notice till they come off. But as soon as I get on the stage it's as if I have energy.
EastEnders star June Brown on Desert Island Discs
EastEnders star June Brown talks about turning 90
I think loneliness and having no motivation, nothing to work towards … I think it kills you
June's appearance on the radio show comes ahead of her her 90th birthday next week. To celebrate the milestone and her time on EastEnders, a special programme has commissioned.
June Brown at 90: A Walford Legend will look at how June initially got the part of Dot, who has gone on to become a British soap icon, as well as her spats with fellow cast members and her most memorable moments on the BBC soap.
Among some of Dot's highlights are going on trial for the murder of her son after she dialled for an ambulance too late and helping her friend Ethel Skinner (Gretchen Franklin) to die peacefully in a controversial euthanasia plot.
EastEnders actress June Brown opens up about playing Dot Branning
Soap stars then and now
Wed, February 1, 2017
From EastEnders' longest running character Ian Beale, to Coronation Street's Sarah Platt, take a look and see how much these soap stars have changed.
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June Brown, star of EastEnders then and now
Ether Skinner and Dot Branning on EastEnders
The soap star is reportedly thought to be the highest paid female actress on EastEnders with Steve McFadden, who plays Phil Mitchell, being thought to earn more.
It is thought that her salary was upped to £300,000 a year after her contract was renewed by the BBC until 2018.
Desert Island Discs is on BBC Radio 4 at 11.15am.