A father is running 500km to raise funds for a charity that supports people with food allergies.

Matthew Watts, from Old Netley, is fundraising for The Natasha Allergy Research Foundation, which supports research for allergies like those affecting his five-year-old son, Charlie.

Charlie has milk, egg, and banana allergies and is on a pioneering immunotherapy trial for his milk allergy at University Hospital Southampton.

Charlie, aged 5, has milk, egg, and banana allergiesCharlie, aged 5, has milk, egg, and banana allergies (Image: Supplied) The £2.5 million study is funded by the charity and aims to find solutions for patients with allergies.

Mr Watts is participating in the Great South Run and completing 12 additional runs as part of the Halloween Great Run Solo event.

In total, he plans to run 500km (or 500,000 meters) by the end of the year.

Mr Watts is participating in the Great South Run and completing 12 additional runs as part of the Halloween Great Run Solo event.Mr Watts, his partner, Charlie's mum, and Charlie meeting Natasha's parentsat UHS  (Image: Supplied) The Natasha Allergy Research Foundation, established by the parents of Natasha Ednan-Laperouse, has been instrumental in transforming the public's understanding of allergies and improving the level of medical care available.

Natasha tragically died from anaphylaxis in 2016 after consuming sesame seeds that were not listed as ingredients on the packaging of a baguette.

Mr Watts praised the clinical team at University Hospital Southampton, stating they have been 'fantastic' throughout the trial.

Matthew and Charlie on the Good Morning Britain sofa when they interviewed Charlie and Amanda earlier this year about the trialMatthew and Charlie on the Good Morning Britain sofa when they interviewed Charlie and Amanda earlier this year about the trial (Image: Supplied)

Mr Watts said: "I want to express my thanks to everyone who has donated to the cause so far, including many family and friends who have worked hard to make and find donations. 

"In particular I have to say a huge and heartfelt thank you to web design and digital marketing company Wattsup Communications, run by my sister Hannah Watts, which contributed a whopping one-off donation of £1,910."