Last month, Lisa Jenkins went for a walk alone around her local park for an hour, the first time she had done so unaided for 13 months. Jenkins was diagnosed with cerebral palsy at the age of three. Now 46, she struggles with vertigo and dizziness, as well as muscle spasms and poor mobility. An Access to Work grant means that she can get a taxi to and from her job in advertising, but for the last three months she hasn’t needed one. The difference? She believes, a few drops of grassy-tasting oil under the tongue each morning.

“I have been using a 5% CBD oil for six months,” she says. “I previously took Duloxetine [an antidepressant medication also used to treat nerve pain] which was initially helpful, but my muscle-freezing episodes came back and I stopped taking it. I was also prescribed Valium, but you can’t take that during the working day.” A friend suggested she try the legal cannabis derivative. She has since been taking it every morning before work, using more during the day if her muscles become tight. “Within an hour of taking those first three drops, my muscles relax,” she says. “The stress in my head calms down. The longer I take it, the better things seem to be.”

Jenkins is one of an estimated 1.3 million UK consumers who spend a total of £300m a year on cannabidiol (CBD) products. The oil contains one of the non-psychoactive chemicals found in the hemp plant – not the illegal mind-altering THC (tetrahydrocannabinol) that gets you high – and has been on the shelves of specialist health food shops and hemp “dispensaries” since 1998. It’s 21 years since the British government first issued a licence for a cannabis extract to be developed for use in clinical trials.

But in the last few years, it has leapt into the mainstream, acquiring the ubiquity of vitamin C and the social status of something much sexier. Most commonly consumed as an oil dropped under the tongue, CBD is also available as gummy sweets, capsules, body salves and e-liquids to vape. A CBD gold rush has led to an explosion of infused products, everything from soft drinks, tea and coffee to ice-cream, toothpaste and shampoo. You can get vaginal suppositories containing CBD (“weed tampons”) that are said to help with pelvic pain; CBD-infused deodorants and sexual lubricant (said to promote relaxation and increase blood flow); even CBD hummus, perhaps to snack on after your lubricated endeavours.

For CBD evangelists, it seems there is no health problem it can’t help – from chronic pain, depression, anxiety and skin conditions to insomnia. Many report that CBD improves concentration, memory and general mood, as well as reducing stress levels. But the products can’t legally make such claims; in the UK, CBD can be sold and advertised only as a generic food supplement. “We never use any medical terminology,” says Johan Obel, director of popular online CBD retailer the Drug Store, standing in front of a huge, gold-framed artwork of a nerve cell in its central London store. “If people come in asking for advice on a specific issue, we tell them to do their own research.” (He adds that their sexual lubricant is “by far one of our bestsellers”.)

The boom in CBD-infused products on the high street is reminiscent of short-lived fads of recent years, such as our brief fixation with chia seeds, turmeric (rendering lattes highlighter-yellow) or spirulina. Only, CBD does not seem to be going anywhere. On a recent walk through London I visited a cafe serving camomile and CBD lattes, passed a yoga studio advertising CBD classes, and a bar serving CBD-infused cocktails. The CBD acronym, with its suggestion of something illicit, is catnip to anxious consumers in need of something they can’t quite put their finger on.

“Most years there is a golden product – a ‘Holy cow, can you believe how much of this we’re selling?’ thing”, says Al Overton, buying director at Planet Organic. “There was the year of quinoa, the year of manuka honey, the year of the goji berry. Now it’s CBD. We have been selling CBD products in our supplement section for just over two years, and it’s been our fastest-growing product in that time. The majority of interested customers are female – especially those who feel that conventional pharmaceuticals aren’t working for them.” He thinks it’s too soon to tell how much of a fixture “infused” foods and drinks will become. “We see oils and capsules as more of a sophisticated and long-lasting trend, but it is early days with the ‘edibles’.”

There is little evidence to support the claims CBD users make. So are we witnessing a global placebo effect?

I have been using CBD oil on and off for two years myself, finances permitting. It’s expensive: a bottle of 1,000mg (10%) CBD oil from Love Hemp, costing £49.99, lasts three weeks on average. I started because I wanted something to help with crippling period pain and associated symptoms, including anxiety. I love the taste; a bitter, herbaceous blast, like a joint dipped in strong extra-virgin olive oil. More importantly, when I take CBD regularly I notice that, when the dreaded week of cramping and gut chaos arrives, my perception of the pain shifts; I am aware of the sensations and their cause, but am less agitated by them. It feels as if the message of pain is being delivered in a different language. But does the science back me up?

***

Between 2002 and 2012 there were nine published studies on the use of CBD for the treatment of pain. By 2017, there had been 30. Almost all have shown potential benefits. However, with their small participant numbers, along with the fact that those participants are mostly rats, it is hard to make reliable claims about the human response. “Very few of the claims for CBD’s effects have actually been, or are being, tested,” says Dr Sagnik Bhattacharyya, of King’s College London’s (KCL) psychiatry, psychology and neuroscience unit. Scientists there have been investigating whether large doses of CBD could help treat severe mental health problems. “We have carried out a couple of studies where we show that a single 600mg dose of cannabidiol can normalise brain function in key regions we know are abnormal in people with psychosis,” he says. KCL now has funding to carry out a large-scale trial to test whether CBD could be useful in treating young people at high risk for developing psychosis. If successful, its new trial will provide “definitive proof” of CBD’s efficacy as an antipsychotic treatment, and pave the way for clinical use.

‘There is currently no evidence to show what regular low doses, like 30 or 40mg a day, are doing.’ Photograph: Ilka & Franz/The Guardian

Meanwhile, Great Ormond Street hospital (GOSH) has published research showing that CBD has potential as a treatment for epilepsy, particularly for children with the severe, drug-resistant form known as Dravet syndrome. The study showed that CBD reduced seizures by nearly 40% for the 120 children who took part in the trial. Prof Helen Cross, consultant in paediatric neurology at GOSH, said: “The results of this study are significant, and provide us with firm evidence of the effectiveness of cannabidiol. This drug could make a considerable difference to children who are living with Dravet syndrome and endure debilitating seizures.”

CBD has also been shown to be helpful for decreasing the myriad symptoms of anxiety. In 2011, scientists from Brazil conducted a trial with people with social anxiety disorder. Participants were split into two groups; one received a single 600mg dose of CBD, the other a placebo. All subjects completed a simulated public-speaking test which involved choosing a topic from a pre-selected list on which to deliver a speech, directed at a television camera as if addressing a large audience. Those who received the CBD dose before the task experienced considerably reduced anxiety levels compared with the placebo group. Preliminary evidence from another trial, completed this year by scientists at the University of Colorado, also suggests that CBD may be helpful to those who struggle with anxiety-related sleep disturbances.

But there is currently little robust evidence to support the claims CBD users make for the oils, coffees and hummus available on the high street. So, if over a million people are finding these work, are we witnessing a global placebo effect?

***

The doses used in clinical trials tend to be much higher than you can buy commercially. “It’s usually between 600-1500mg, either as a one-off or repeated dose,” says Dr Chandni Hindocha, a research fellow with University College London’s clinical psychopharmacology unit, and part of a team researching whether CBD can help treat nicotine and other addictions (the results are promising so far). Hindocha emphasises the need for more research into dosing ranges. “There are no observational studies about the lower-dose products people are taking right now. We have no idea how much they’re taking and why they’re taking it.”

In the clinical trials Hindocha has worked on, most participants cannot differentiate between a 100mg dose of CBD and a placebo. “If most people are getting something like 50mg of CBD in a bottle, we need to think about what is going on,” she says. In her opinion one-off doses of CBD in popular edibles are unlikely to have any effect. “We know that the beneficial effects of CBD usually come from building up levels of it in the body,” she explains, but this is with the high trial doses. “There is currently no evidence to show what regular low doses, like 30 or 40mg a day, are doing.”

But what about the vast amount of anecdotal evidence for its efficacy, particularly in helping with chronic pain? Dee Montague, a press officer from Newport, Wales, was diagnosed with endometriosis in 2018, 18 years after first going to the doctor. The impact on her life has been striking. “I played roller derby for eight years but had to quit due to the pain and fatigue. I am completely exhausted by the time I get home from work and can barely function.”

‘The majority of interested customers are female – especially those who feel that conventional pharmaceuticals aren’t working for them.’ Photograph: Ilka & Franz/The Guardian

She finds that CBD helps. In 2018, she began to experiment with an oil. “It took a week of regular doses to make any difference,” she says, but she was pleasantly surprised. “I found my cramps were far less intense. My sleep improved slightly, which made a real difference to my quality of life.” She then switched to a skin balm, because “the guidance is to avoid taking CBD oils within two hours of other prescribed medication” and she relies on daily medication for asthma. Montague has now been using a CBD-rich skin balm for a year, applying it to her stomach and pain spots on her legs every morning and night. The 100g jar she buys contains 1,000mg of CBD; Montague admits it is hard to know exactly how much CBD she is using each time, and does not view it as “a cure or painkiller, as such”. But the side-effects are nonexistent compared with opiates, she says. “ I feel far more in control of my pain and day-to-day life.”

CBD works by affecting the function of our endocannabinoid system (ECS). Made up of neurons (nerve cells), endocannabinoids (cannabis-like substances the body makes naturally) and cannabinoid receptors, the ECS is responsible for regulating the body’s systems to maintain homeostasis: keeping our internal temperature, blood sugar and pH levels balanced, along with the amount of water in the body. It tells the body when to start sweating (to cool down) and when to stop. Everything from chronic pain to migraines and epileptic seizures have been linked to ECS deficiency.

It is thought that when we introduce a new cannabinoid into the body, such as CBD, it binds with these receptors and, like a molecular power-up, increases the amount of natural cannabinoids in the body. CBD has also been shown to bind with receptors for serotonin (our feelgood molecule) and GABA (the molecule that calms the nervous system), increasing the amount available to the body – offering a potential explanation for CBD’s reported calming effects.

I asked Hindocha whether stories such as Montague’s suggest that such small doses could be having an impact? “It is very interesting,” she says, “because there is an argument that low doses of CBD could potentially affect inflammation in the body.” One complicating factor is metabolism. “When someone takes CBD oil, much of it will be broken down by the liver,” Hindocha explains. “Without knowing about their metabolism, we have no idea how much CBD they’re really absorbing.”

***

Before you can consider how much you’re absorbing, you need to know how much you’re taking in the first place: this year a major study by the Centre for Medicinal Cannabis found that 38% of CBD oils contain less than half the amount of CBD stated on the label. Almost half (45%) of the products contained more than 0.2% of THC (the Home Office’s legal threshold) and, therefore, were technically illegal in the UK.

Browse the CBD shelf in your local health shop and you’ll find a huge variation of strengths on offer; but a higher CBD content means a higher price. Holland & Barrett sells a 10ml bottle of oil by Jacob Hooy containing 5% CBD for £29.99; Boots stocks 10ml bottles by Dragonfly containing 11.1% CBD for £70. One of the strongest products available is by Love Hemp: a 10ml bottle with 40% CBD, for £259.99. Love Hemp suggests a maximum daily dose of 200mg; while it is thought impossible to overdose on CBD, most producers offer guidance on dosing. I notice that none of the infused products carry warnings about maximum doses, age limits, or driving.

Women want to be responsible for their own health. They want more options than those offered by traditional medicine

Hemp can be legally grown in the UK with a government licence, but is an incredibly small sector. It is estimated that only 810 hectares (2,000 acres) of hemp are currently cultivated in the UK’s 42m acres of agricultural land. When I visited a couple of rough-and-ready CBD outlets in London which, as well as oils, sold whole hemp flowers in clear plastic bags, it made me nervous about where it came from. I was routinely assured the flowers contained less than the legal 0.2% of THC. But how can a layperson, without access to a lab and a scientist to test it, really know?

The nice man running one of my local CBD shops – a modest outfit selling oils, e-liquids, balms and bongs – offered me tea and lots of convincing chat, but agreed that dosing essentially comes down to experimenting. The smell of his shop instantly, rather thrillingly, transported me to the top of the multistorey car park in Bishop’s Stortford, the locus of my teenage experimentation with marijuana. Perhaps that whiff of transgression contributes to CBD’s seductiveness? Even if we know it won’t get us high, it’s wellness with an edge.

The Drug Store’s Obel tells me that nearly all the CBD products in the UK originate from the same wholesalers; the extraction equipment is too expensive for smaller companies. “It takes a long time to figure out how to do it properly – only a few people actually have the knowledge,” he explains. In most cases, producers simply add the extract to their carrier oil of choice and put a new label on it.

Obel says the majority of his customers are women aged 40 and above. The audience for a recent in-store event, a panel discussion on the impact of stress, was 80% female. “From what we have seen, women want to self-educate and be responsible for their own health. They want to seek more options than those offered by traditional medicine,” he says. He does not believe the boom in CBD-infused high-street products like chocolate, tea and hummus will last: “We believe everyday products with CBD added will fade away. Products in which CBD is the actual active ingredient, or where CBD serves a specific purpose in supplements or cosmetics – those will most likely remain.”

***

That we currently have no idea of CBD’s full potential is at once incredibly exciting and frustrating. Without more dedicated research, the commercial market will remain something of a wild west. Meanwhile, people will continue to inform themselves, spending their money on products with, it seems, woolly efficacy. The costs will remain prohibitive to many. Meanwhile brands will continue merrily infusing their teas and ice-creams with nominal amounts of CBD, knowing that people will pay extra for the buzz cannabis brings.

I am now thinking more carefully about my own experimentation. Unless I pay close to £300 on a regular basis, for the highest strength of CBD oils commercially available – the only products that come close to what is being clinically tested – it strikes me that I may be experiencing a placebo effect. Then again, with the research in its infancy, I might not. So I will finish the bottle I have. Beyond that, the question is: how much am I willing to pay for a maybe?

A touch of grass: high-street CBD, taste-tested

Buddha Teas CBD Matcha Green Tea Blend (18 bags), £16.99

They say “Our innovative process ensures that the CBD in our tea bags actually ends up in your tea.”

CBD count 5mg per bag

Our verdict “The taste is very subtle and the bags can rip, but I was surprised at how easily I fell (and stayed) asleep – I’m normally a very light sleeper.”

Themptation Hemp Chocolate Spreadables CBD vanilla spread, 165g, £5.05

They say “More seeds than sugar, more hemp than any other ingredient, packed with 10mg of organic CBD oil and vanilla.”

CBD count 10mg

Our verdict “This is so delicious and wholesome-tasting, it’s hard to separate that feelgood factor from any CBD effect. Definitely moreish; keep away from kids.”

Aussie ‘calm the frizz’ Shampoo, 300ml, £3.99

They say “Our miraculous formula, with Australian hemp seed extract, will tame your mane in next to no time.”

CBD count Some cannabis sativa seed extract.

Our verdict “Foamy and minimally scented, this resulted in noticeably softer, smoother hair. Was that the hemp? I liked it more than other Aussie shampoos.”

Wunder Workshop turmeric x CBD Raw Chocolate Bliss bar , 40g, £6.99

They say “With cacao from Peru; turmeric from Sri Lanka; and boosted with CBD.”

CBD count 16mg

Our verdict “I liked the taste – definitely got the turmeric – but no obvious relaxing effect.”

Nooro raw, vegan oat CBD bar in Cacao & Coconut, 45g, £2.95

They say “Our CBD is sourced from a small independent UK grower.”

CBD count 25mg

Our verdict “Pleasant initially, but followed by a soapy aftertaste. Quite sickly.”

BumbleZest ginger, turmeric and CBD shot, 60ml, £3.15

They say “A natural fiery drink with a lemon base, designed to be taken as a health shot on the go.”

CBD count 2.5mg

Our verdict One tester found it “very acidic, quite unpleasant, made me sneeze”. Another loved the fieriness: “I felt energised and set up for the day. Or it could have been my morning swim.”

The Marshmallowist limited edition marshmallows, £15 for a box of six

They say “Crafted from organic CBD-infused mallow whipped to create a super-light texture. Do not exceed two marshmallows per day.”

CBD count 10mg per marshmallow

Our verdict “Great flavours (choose from cocoa, blood orange or grapefruit), very fluffy, not too sweet, these started life on a market stall and still have that premium feel.”

Drink 420 – CBD infused elderflower & lime or wild berry drink; 250ml, £2.29

They say “Water. Zingy fruits. The legal bit from cannabis. Plant extracts. What could be purer?”

CBD count 15mg

Our verdict “Nice: there was something dry and hempy beneath the zing. I felt a bit spaced out – but was it the placebo effect?”

Themptation CBD Hummus, 190g, £4.75

They say “Packs an anti-inflammatory punch with a delicious herby sage taste.”

CBD count 13mg

Our verdict “I liked the grainy texture, but there was a strange aftertaste. I ate half the pot without thinking about it and felt spaced out afterwards – dinner at my mother-in-law’s was a very relaxed affair.”

Tested by a very chilled Guardian Weekend team

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