Take this — superwater with the magic herb that could help you live to be 100

David Spencer-Percival thinks he can help us live past 90 or, at least, fend off the ills of old age if we drink his superwater. “My Nan has got dementia, my wife is 21 years older than me, and I don’t want her, or me, to get dementia,” said the entrepreneur. “People should drink it, it’s healthy.”

He set up his third venture, Rosemary Water, with £2 million of his own cash last year, and it’s now stocked by Harvey Nichols, Whole Foods and Ocado while fashion designers Stella McCartney and Victoria Beckham swear by it, he claims. Take That’s Howard Donald has backed it.

The entrepreneur has already co-founded and exited two multi-million pound recruitment businesses, Huntress and Spencer Ogden.

The idea for his posh drinks business struck him after he read an article about Acciaroli, a village in south-west Italy, famed for its rosemary-chewing centenarians. “They’re living to 100 in vast numbers and that’s because they eat it,” he said.

It may sound like an ancient herbal cure, but a handful of scientists have recently said rosemary could help treat common conditions such as arthritis, improve eyesight and boost memory. This made him think how he could bottle those key ingredients — rosmarinic acid, eucalyptol, glucosamine — and sell it as a healthy botanical drink.

He sought help from a specialist manufacturer in Herefordshire to extract the essence from the sprig.

Spencer-Percival admits starting a new brand is no easy gig. “If I would have known half the complications of how to get a drink onto a shelf, there is no way I would have done it,” he laughed. “If you’re small you get this impossible barrier that you have to cross before anyone takes you seriously.”

He had to rustle up a further £1 million from high-profile investors including Donald, Lord Leigh and Carrie Wicks, who used to run Firmdale hotels, in return for a minority stake to get it off the ground. His gamble is paying off.

The water comes in 330ml and 750ml bottles, infused with rosemary extract from batches harvested every three months near Acciaroli, and he hopes to grow his own crops close to his Cotswolds retreat. The drink is refreshing. You get a hint of rosemary but there’s no danger you’ll spit it out. However, parting with as much as £3.95 for a bottle of water in shiny, white packaging seems an extravagance or, maybe, just a rip-off.

“It’s expensive for a reason,” he counters. “We don’t make it because we want to make lots money — because we are losing lots of money. It costs what it costs because we’re small. My mission is to make it cheaper.”