A brain-enhancing coffee sounds tempting, doesn’t it? What’s not to like about a daily shot containing not just the caffeine that 75% of us rely on to get going most days, but also a sprinkling of adaptogenic plant or fungal extracts?

Adaptogens are substances found in plants and fungi – and are big business. Theoretically, they have brain-boosting, focus-enhancing, mood-improving, stress-reducing properties. They are widely sold as supplements, but one of the fastest-growing new markets is for adaptogenic or functional coffee.

So, is this the end of the plain old flat white? Will your next espresso come with stamina-increasing ginseng or mineral-rich roasted chickpeas? Do they live up to the marketing hype? And perhaps most importantly, is coffee laced with cordyceps mushrooms even drinkable?

Before you rush out to buy a bag, you should know that despite the big claims, clinical evidence for many adaptogens is pretty scant (although there is plenty of research on the go). And, while many have been safely and effectively used in traditional medicine for thousands of years, what humans haven’t ever done before is take them every day, with caffeine (in itself a psychostimulant, sometimes used in medicines) and maybe even a dash of CBD. (For those who don’t want caffeine, there are decaf versions, as well as new coffee alternatives made with a range of roasted and ground stone fruit and legumes.)

Reishi mushrooms, for example, have long been used in Asian medical practices as an immune response stimulator, while maca is a Peruvian root vegetable used by Andean people for chest infections, and which may also enhance sex drive. Ashwagandha is a shrub used in Ayurvedic medicine to treat stress and anxiety and increase energy levels. Cordyceps is a parasitic zombie fungus that infects, lives on and kills adult insects and larvae (mmm, delicious) used in traditional Chinese medicine for more than two millennia to help with energy and stamina. But until now, no one has stirred a teaspoon of any of them into hot water every morning.

Adaptogens were first named in the 1950s by Soviet toxicologist Nikolay Lazarev, who noticed that consuming certain plants seemed to increase human resistance to, and tolerance of, physical, biological or psychological stress, without themselves causing harm. Initially, only a few plants, all used in traditional medicine systems, were considered adaptogenic: Siberian ginseng and Rhodiola rosea, a flowering plant from the Arctic regions, were among the first to be studied – both are thought to increase energy and stamina.

But today, dozens of plant extracts and supplements are thought of as adaptogenic, including a wide range of “functional” mushrooms, even though they don’t necessarily meet the pharmacological definition and haven’t been studied much, if at all.

Your social media feeds may be full of adverts making a noise about the brain-enhancing benefits of lion’s mane mushroom coffee, but research into this strange, hairy looking fungus has so far mainly looked at animals or cells in-vitro, rather than humans (a small randomised controlled study looking into lion’s mane as a treatment for Parkinson’s disease will finish soon). That doesn’t mean that all adaptogens definitely don’t work, but it does mean we don’t yet know much about dosages, interactivity or long-term effects.

Prof Michael Heinrich is a pharmaceutical biologist with a special interest in medicinal plants, and is part of the pharmacognosy (natural drugs) and phytotherapy research group at the UCL School of Pharmacy in London. He believes that at present many of the claims made for adaptogenic or functional plants cannot be substantiated.

“The worry I have is that adaptogens are becoming the new antioxidants – a catch-all marketing phrase. I’ve seen claims that fungi can relieve anxiety, prevent wrinkle formation, stabilise blood pressure and ease hot flushes. This is just completely unacceptable. These are very strong medical claims. I think there are some useful things to be learned from a proper use of adaptogens, but for most of these, the clinical evidence is somewhere between nil and extremely limited.”

Although interactivity between adaptogens and other medicines taken at the same time may be a concern (just as with any pharmacological item), Heinrich also questions whether products such as enhanced coffees contain high enough doses of adaptogens to do anything much. He took part in a global study of Gingko biloba supplements, which revealed that many products either didn’t contain what they claimed, or contained other, potentially dangerous ingredients.

“With mushrooms, we also need to remember that they can accumulate heavy metals – plants grown in soils rich in or polluted by metals such as lead or cadmium can be harmful to human health – and we don’t know how they’re grown, on what soil or medium, where the water to irrigate is from. To my knowledge, that has not been looked at systematically.”

Heinrich would also like to see certain adaptogens given higher pharmacological status and be treated, more cautiously, as medicines rather than foods.

“I think ashwagandha, for example, should be much more stringently regulated as a medicine. If the dose is quite low, it’s unlikely to do anything, but there are interaction risks.” He also notes that although adaptogens are marketed as though they’ll help you out immediately, like caffeine, “By definition, adaptogens have a long-term, slow and modulating effect.” My week of trialling them certainly didn’t make me feel any different.

Adaptogenic coffee isn’t cheap, either – a 200g jar of ordinary instant coffee (as bought by 80% of UK households) will make about 100 cups of coffee at less than 10p each and a home-brewed ground coffee works out at 30p-45p, whereas adaptogenic coffee can cost more than £1 a serving.

If you don’t fancy enhanced coffee, you could try one of the many other caffeine-free coffee alternatives that are vying to push turmeric lattes out of the limelight.

Chickpea coffee is made from blackened, roasted chickpeas which are then ground and brewed just like coffee (like chicory or barley “coffee”, this is not a novel invention, having been drunk by communities in India and Turkey for generations). It can be made at home or bought online: look for new US brand Alt Health, which claims its cuppa is rich in fibre, potassium, iron, magnesium, selenium and calcium. Or there’s maya nut coffee, from Costa Rica, sold by Blue Zones Nicoya, a company set up by longevity researcher Dan Buettner. It’s made with the highly nutritious maya fruit, also known as breadnut, and flavoured with spices.

Starbucks recently launched Oleato, a range of olive-oil enriched coffees. They are not unlike bulletproof coffee, a high-fat, carb-free coffee favoured by ketogenic diet followers, which is made without milk but with both butter and oil. The Oleato range is either served with olive-oil-infused oat milk or black with a drizzle of olive oil added to the cup. (Howard Schulz, founder of Starbucks, is an olive oil super fan and started drinking a spoonful every day in 2022, at the age of 69, having heard that long-living Sicilians do the same.)

Although the grassy flavour the oil adds isn’t unpleasant, exactly, it’s impossible to ignore that the added fat makes the coffee taste greasy; an Oleato latte feels even richer than a pumpkin-spiced venti.

Or how about a lavender latte? Perhaps more Instagrammable than palatable, this coffee is made by whisking dark purple, ready-made lavender syrup into milk, and then layering it over espresso, which looks – and tastes – likes coffee mixed with bubble bath. I’ll stick to my flat whites, thank you.

That’s not coffee! The taste test

Antioxi Focus chaga- and turkey tail mushroom coffee
The amount of mushroom extract in this is high, which explains the earthy flavour, and the way it turns a bit mushroom soupy once you add milk. The packaging says the ingredients are heavy-metals tested, and lab reports are published on its website.
150g/30 servings, £19.99, antioxi.co.uk

Pardasa sea moss-infused mushroom coffee
Saline and ozone notes make this coffee, with chaga, lion’s mane and cordyceps mushrooms, an unusually savoury drink. At first gulp, the vegetal hit of seaweed is a bit surprising, but it steadily mellows. Best with milk – or mylk.
150g/60 servings, £32.99, pardasa.co.uk

London Nootropics
The Flow blend, with lion’s mane mushroom and rhodiola, opens with a floral burst of turkish delight. The Zen blend is less in-your-face, as though jasmine tea and coffee have been made in the same pot. Mojo is more bitter until you add milk, when chocolate notes come through.
12 sachets £15, londonnootropics.com

No Ordinary Moments Moksha decaf coffee
With added milk, this is basically a chai latte. If you like chai spices, there are plenty of them, as well as lion’s mane, reishi, chaga and cordyceps mushroom, cacao, maca and turmeric, cinnamon and vanilla. The mushrooms are undetectable.
30 servings £32, noordinarymoments.co

Rara Coffee
Definite ’shroomy flavours here, from lion’s mane, reishi, chaga, cordyceps, turkey tail and shiitake, and a lingering mushroom aftertaste. The coffee base is ethically and sustainably sourced.
100g, £14.99, raracoffee.co.uk

Dirtea coffee
This is the least earthy, and most reminiscent of a normal cup of coffee, despite its blend of lion’s mane, chaga, and tremella plus ashwagandha and maca. You could have a cup of this with a croissant.
150g, £35.99, dirteaworld.com

Blue Zones Nicoya
I wanted to like this – maya nut contains essential amino acids as well as minerals and vitamins – but it tasted like wet mud with a hint of chocolate. The spiced version is better, especially with milk.
500g, $18.99, bluenicoya.com