Marathon man Gary McKee says he's being fuelled by Jaffa Cakes and tea as his gruelling charity challenge enters its final straight.

His 100 marathons in 100 days feat has seen him run 26.2 miles every day for charity since January 14 to raise money for Macmillan Cancer Support.

The 47-year-old Cumbrian will complete his mammoth challenge when he crosses the finish line of the London Marathon next Sunday, by which time he will have covered more than the equivalent distance of London to Newfoundland in Canada, some 2,620 miles.

Mr McKee, from Cleator Moor, hopes to raise £50,000 for the cancer charity, which he has supported since his father Victor was diagnosed with lung cancer 20 years ago.

He has been juggling running around his home town every day with his job at the Sellafield nuclear complex and looking after his and wife Sue's children, Alfie, 12, Beau, nine, and Minnie, four.

Covering at least 26.2 miles every day requires huge amounts of energy, and despite "eating like a horse" to fuel the 5,000 calories he burns off each time he has still lost three stone in weight since he started out.

He said: "In a typical day I have a couple of bananas, toast with jam and a mug of coffee for breakfast, before setting off on my run.

"I split my marathon into two sections, so I'll run 13.5 miles before lunch - either soup and a sandwich or pasta. I'll also have Jaffa Cakes or some flapjack and a couple of mugs of tea.

"Then I do the second 13.5 miles, before a big meal of protein and carbohydrates for dinner and another protein drink before bed. It's really important to try and maintain muscle mass for strength, so I've been eating like a horse but I've still lost weight."

He added: "I've had such incredible support so far, with people joining me on my runs to keep my spirits up and cheering me on. But my wife Sue is my biggest supporter and without doubt I couldn't do any of this without her.

"It is a difficult challenge because of the enormity of it all."

Mr McKee's father beat cancer but died in 2003 from an unrelated illness, and since his initial diagnosis his son has climbed mountains, trekked, jumped out of aeroplanes and walked over fire to raise £150,000 for the charity.

He said: "I wanted to do something in my dad's memory and thought back to that day when we first found out he had cancer.

"I became a fundraiser for Macmillan Cancer Support because I realised people all over the country were going through what we had gone through.

"It hasn't been easy but when it gets hard, I think of the promise I made to people affected by cancer - that they're not fighting alone and I'm fighting with them.

"I'm not a superhero, I'm just an ordinary bloke trying to make a difference to people affected by cancer."

Sally Tibbitt, from the charity, said Mr McKee's efforts were "absolutely outstanding".

She said: "We are so impressed by Gary's determination to go the extra mile to help thousands of people living with cancer and his fundraising will make a huge difference to so many."

For more information or to sponsor Mr McKee, visit www.justgiving.com/fundraising/Gary-McKee100. Those wanting to undertake their own running challenge for the charity can visit www.out-run.org.uk.