Gone are the days when having a 'health drink' meant a glass of orange juice with the bits left in. Even birch and cactus water feel a bit outdated, now everyone's got a Nutribullet and started making their own lurid-coloured smoothies that profess to do everything from recolonising your gut to reorganising your mind.

But there's a brand new kid on the healthy beverage block, with a distinctly chalky texture and yet the colour of ink: charcoal - in cold pressed, liquid form. Sound appetising? Not a bit. But what was once the preserve of Gwyneth Paltrow and her tribe of smug Goop devotees - who have named charcoallemonade one of the "best juice cleanses" around - is what those in the know will supposedly be quaffing, come January.

To be fair, Michelin-starred restaurants have had the black stuff on their menus for some time - top chef Simon Rogan serves up ox cooked in coal oil and potatoes with onion ash at his restaurant L'Enclume in Cumbria. The hipsters are (obviously) already onto it, too; several trendy Shoreditch clubs list charcoalon their cocktail menus, with one bar - Bull in a China Shop - offering a chamomile and charcoal Old Fashioned, made with whisky, chamomile syrup and a sprinkle of coconut charcoal.

Until now, however, the rest of us have probably only come close to ingesting the stuff when dealing with a particularly nasty stomach bug; charcoal tablets are said to bring effective relief.

In fashion; readily available

But charcoal has lately gone the way of turmeric root and ginseng and started to become more and more readily available.

Some supermarkets have already bought into the trend, with Waitrose stocking a charcoal and chia seed-topped bagel in its Heston Blumenthal range (on sale at 3.60), along with boxes of charcoal and sesame biscuits to go with cheese (2.49), and a cold pressed charcoal juice for an eye-watering 5.99.

The bagel and biscuits are fairly harmless, but the juice, made by London based company Botanic Lab, is serious stuff. Packed with raw cane grass (nope, me neither), lemon juice and yuzu fruit, upon first sip it tastes rather like a particularly tart lemonade - but leaves a lingering salty, powdery aftertaste.

It may not be to my palate, but Waitrose customers are clearly on board: since its launch in September it has seen a steady increase in sales, with a 100 per cent rise month on month. So popular, in fact, that more charcoal products are on the way in 2017, and it's surely only a matter of time before the other supermarkets follow suit.

Health benefits

Let's be clear, they won't just be flogging the powdered detritus from your wood burning stove. Derived from peat, coal, wood and coconut shells, the medical grade charcoal used for health foods is 'activated' by heating common charcoal with a gas which increases its surface area and increases its internal porosity. When ingested, these pores enable the charcoal to absorb toxins and other bad substances - hence its traditional administration in emergency rooms to treat poisoning or drug overdoses - which, along with its supposed de-bloating and teeth whitening properties, is why the substance has been on every lifestyle blogger's must have list.

Nutritionist to the stars Amelia Freer (most recently responsible for transforming Kirstie Allsopp and James Cordon and into shadows of their former selves) sings its praises, explaining how charcoal juice "binds with toxins to speed their safe elimination from the body" and rehydrates "more effectively than water". According to Freer, charcoal is "poised to become a mainstay of the cleanse ritual".

Reason to be wary

Charlotte Stirling-Reed, registered nutritionist and media expert for the Nutrition Society, urges a little more caution: "With regards to its use in standard products, I would be a little wary," she says.

"I would recommend that the public see their GP before taking any supplements containing charcoal as it can affect absorption of medicines and might not be appropriate for breastfeeding and pregnant women.

"I would also suggest that anyone concerned about their health or bloating should visit the GP to assess the root cause of the problem before self-diagnosing."

On balance, I think I'd rather water my plants with the stuff than drink it myself, but it's certainly invigorating, and I can imagine it might be an effective stomach settler. Perfect for New Year's Day morning, when your body is crying out for the feasting to cease. Or perhaps this time next year, we'll all be on the charcoal daiquiris, come New Year's Eve.