Indeed, Her Majesty is not only devoted to homeopathy, which she also uses on her animals, but the broader spectrum of alternative medicine - and it is said that her avoidance of illness during her 60 years on the throne is due to supplementing her conventional medical regime with herbal remedies.

But it is Prince Charles, famously so in tune with nature that he talks to plants on his Highgrove estate, who is alternative medicine’s staunchest supporter among the Royals - and indeed one of its most enthusiastic advocates in the UK. The practice is, he told the World Health Assembly in Geneva in 2006, “rooted in ancient traditions that intuitively understood the need to maintain balance and harmony with our minds, bodies and the natural world”.

Though his interest in the subject dates back to his childhood, Charles’s public devotion to alternative medicine first became clear in an address to the British Medical Association in December 1982 on the 150th anniversary of its foundation. Charles, sitting in his study at Highgrove, was struggling for inspiration on what to say and wandered over to his bookshelf, where he picked up a tome about the 16th-century physician Paracelsus.

After reading just a few pages, the ideas crystallised for what the medical profession described as a “seminal outburst”. “I have often thought that one of the less attractive traits of various professional bodies and institutions is the deeply ingrained suspicion and outright hostility which can exist towards anything unorthodox or unconventional,” he told guests. “I would suggest that the whole imposing edifice of modern medicine, for all its breathtaking successes, is like the celebrated Tower of Pisa, slightly off balance.”