Newly crowned double Olympic champion Mo Farah is expected to turn his attention from beating the rest of the world to feeding it today at a Downing Street "hunger summit".
The Somalia-born athlete has been invited to join international politicians and other sporting greats at the event which is designed to shine the spotlight of the Games on the issue of child malnutrition.
Prime Minister David Cameron hopes to secure sufficient commitments from leaders and multinational firms to help prevent 25 million children under five suffering stunted growth by the time of the 2016 Games in Brazil.
Farah, who has set up his own charity to raise money to help the victims of the severe drought in the Horn of Africa, will attend if he is able after the exertions that saw him win the 10,000m and 5,000m finals.
The summit is bringing together leaders and senior politicians from Brazil, Kenya, Bangladesh, India and Ireland as well as sporting greats such as Ethiopian distance runner Haile Gebrselassie and football star Pele.
Britain will promise a £120 million investment in drought-resistant crop research, help for schemes such as a text message hunger alert system in Kenya and pressure on multinational firms to play their part.
Another of Team GB's gold medal winners, long jumper Greg Rutherford, is among signatories to an open letter urging Mr Cameron to "fire the starting gun on the biggest ever push against hunger and malnutrition".
The event will begin with youngsters, including a Tanzanian boy who has suffered malnutrition, racing up a running track to the front door of Number 10 to deliver a plea for help.
Cameron will tell the summit: "While people around the planet have been enjoying and competing in these Games there's another world where children don't have enough to eat, and never get the start in life they deserve.
"It is a tragedy for them, and it's a tragedy for their societies they live in. Children who could grow up to become doctors, farmers, engineers and entrepreneurs or great Olympians are left far behind.
"We've a responsibly to tackle this. But the hard truth is that while we've made huge strides in the last decade on things like education, malnutrition rates have stagnated.
"I'm determined that Britain helps change this."
He will add: "We've just seen in the Olympics what the world can do when it puts its mind to a task. We've got political leaders and great Olympians here. We can't turn away from this and we won't."
The joint letter was also signed by double medal-winning gymnast Louis Smith, judo silver medallist Gemma Gibbons, 10,000m winner Tirunesh Dibaba from Ethiopia and five GB Olympians.
It was organised by aid charity Save the Children which said that on present trends there will be more than three million more stunted children across Africa by the time of the Rio Games.
The athletes told Mr Cameron: "With world leaders gathered in London and the eyes of billions focused on Britain, the Olympics is an incredible opportunity to change the destiny of millions of children round the world.
"As athletes, we know how essential nutritious food is for people to flourish physically and mentally. Despite an abundance of food worldwide, one person in seven goes to bed hungry every night and it is children who are often hit hardest."
They went on: "It doesn't have to be like this. Our world has enough food for everyone. We know how to fix the problem - and we're asking you to rise to the challenge.
"We are delighted that you have shown your commitment by hosting a major hunger event at the Olympics. We're urging you to use that moment to fire the starting gun on the biggest ever push against hunger and malnutrition by committing to put these issues at the top of the UK's G8 presidency next year.
"The eyes of the world are on London 2012. The best legacy the Games can leave is a world where strong, healthy and well-nourished children can achieve their full potential in life."
Tanzanian youngster Frank Kapeta, 15, who is one of the youngsters acting as ambassadors for Save the Children's nutrition campaign, has been flown in from Dar Es Salaam for the summit.
He said he had been inspired by watching the Olympics but said poverty and hunger could thwart his and other youngsters' dreams.
"There is a lot of talented people in Tanzania and the whole of Africa but it's hard to develop these talents and become a hero if you don't get enough food and a variety of nutrients."
Asked about inspiring young Africans at his post-race press conference last night, Farah said: "I am very lucky, I came to Britain just as a kid, but there's kids out there who would love to have a chance and I know they are good at running.
"But for me, when I went not long ago to Somalia and then I saw the kids, the poverty was very bad. I set up the Mo Farah Foundation which is a charity which supports them.
"We deliver food, water, water wells, so I am trying to give back as much as I can because I know there're a lot of kids out there who would love to have a chance."
Campaign group Baby Milk Action welcomed the summit but sounded a note of caution about the involvement of the private sector.
It said in a statement: "There are many underlying factors that exacerbate food shortages and hunger, but when public private partnerships with companies who profit from selling unhealthy products are promoted as the solution there are many risks.
"Partnerships, by their very nature, involve shared decision making. This can lead to the control of marketing practices that undermine breastfeeding and sustainable, affordable, nutritious family foods being overlooked in favour of voluntary approaches, 'market-led' strategies and corporate-funded education programmes and the double burden of malnutrition - both under- and over-nutrition.
"If governments are serious about finding long term sustainable solutions to hunger, it's essential that they address conflicts of interest adequately and protect their health policy planning and implementation processes from undue influence from commercial companies."