Sinead Harmey, based in Norwood, embarked on this impressive feat in October as she prepares for a risk-reducing mastectomy.
She is genetically predisposed to breast cancer due to an ATM gene mutation and is on the waiting list for surgery.
Following advice to lose weight, eat well, and exercise regularly, she decided to focus on lifestyle changes instead of surgery.
The 48-year-old, originally from Kildare, Ireland, has adopted a lifestyle focused on prevention through diet, exercise, and regular screening.
After moving to London in August 2017, she became an associate professor in literacy education and director of the International Literacy Centre at UCL Institute of Education.
The start of 2025 brought new challenges for Sinead.
She received a letter from the genetic service at St George’s Hospital suggesting it was time to re-evaluate her risk due to the increased understanding of the ATM gene and its variants.
She said: “There’s now more research and understanding of the ATM gene and its variants, which meant that my risk had increased.
“Combining that knowledge with my family’s history was significant, as there are cancers on both sides of the family; my dad passed away with bile duct cancer.
“That’s what risk is.
“It’s the sum of all parts.
“I got a letter a month later that I was eligible for risk-reducing surgery.”
After months of research, Sinead decided that risk-reducing surgery was her best option and is now on the NHS waiting list.
She said: “Waiting is hard, but it isn’t as emotionally stressful as making the decision.
“But it helps you to be more present because you can’t plan far ahead.
“Even going or not going back to Ireland for Christmas.
“I’ve seen everyone I’m supposed to see at the hospital, and I’m just waiting until there’s a place for me.”
In October, Sinead decided to celebrate her birth month and the benefits of walking on her mental health by committing to walk 300km to raise money for Breast Cancer UK.
She said: “Walking helps me reflect and manage stress.
“I throw my headphones on and it’s just headspace.
“Sometimes when I’m walking, I leave people long voice notes, listen to a podcast, or walk quietly.
“I like BCUK’s ethos of movement and empowerment to reduce the risk and walking has been my saviour, so I think it’s a good focus.”
Sinead’s daily walks average 10km and range from her routine in London to visits to Ireland.
In the past, she walked four days on the Camino de Santiago trail in Spain and hopes to do that again.
She said: “It sounds a lot, but it’s amazing how little tweaks add up your steps.
“For example, I work in London, so I get off the tube at Tottenham Court Road and walk to Bloomsbury and back.”
Sinead’s fundraising has already reached almost £1,500, which she will conclude with a university seminar, complete with cakes.
According to Breast Cancer UK, being active can reduce the risk of developing the disease by around 20 per cent.
If you would like to donate to Sinead’s cause, visit her JustGiving page.
If Sinead’s story has inspired you, visit the Breast Cancer UK website to find out how you can start your own fundraising efforts.
