Many years ago, the advertising slogan went: "Lucozade aids recovery." Well now, it has gone a step further – by keeping a little boy alive.
Archie Koncher, 10, is one of just three people in the country with Propionic Aciduria which means his body converts protein into lethal toxins which damage his vital organs.
He is limited to just 25g of protein a day - equivalent to a pint of milk - and any more than that could kill him.
The genetic disorder is incurable but brave Archie is beating it by drinking up to four bottles of Lucozade a day, which gives him the energy he cannot get from food.
His daily intake of the drink contains a whopping 33 teaspoons of sugar - and costs his parents £120 every month.
Archie, from Stoke Orchard, Glocs., was diagnosed with Propionic Aciduria when he was two years old.
His parents immediately swapped his normal milk and baby food for non-protein food and saw an overnight change.
Archie, who weighs barely five stone, now eats tiny portions alongside his parents and older brother Charlie, 16, but carefully avoids high protein foods like fish.
He drinks up to four 380ml bottles of Lucozade a day, each containing 33g of sugar.
Mum Salli said: "We are very lucky he is still alive - it is a silent killer. You just don't know what can happen.
"When he gets very lethargic, we have to be careful. When he vomits, we have to get him to hospital immediately.
"He can't have too much protein. When we go to McDonald's for a treat, he has to have the chips, and only half the burger, with no bun.
"For him, an egg is a treat. He can't have any more. It's heart-wrenching.
"We don't know what the future holds but we are just happy that he is a happy little boy and loving life."
His dad Dave, 45, said: "Lucozade just keeps him going - we wish we could get it on prescription.
"If he is starting to feel a bit tired, maybe after he has been running around, it will just pick him up again straight away.
"Without a doubt, without that drink, we would be in serious trouble. We've tried all sorts of different foods but this is the one for Archie."
His dad added: "He eats a lot of carbs too, like crisps and noodles, with the Lucozade too of course and anything high sugar.
"When he is well you wouldn't know there was anything different about him, but he is about the height of an eight-year-old simply because he is eating so much less."