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CBD: Helping you weed out the facts

You’ve probably seen ads about CBD oil, or other products containing CBD, claiming everything from cancer prevention to clearer skin. But what is CBD? Can these wild claims meet expectations? We help lift the fog over CBD, so you can decide whether it’s something that can help you.

What is CBD? 

A cannabis plant produces several chemical compounds known as cannabinoids. The two most well-known compounds are called CBD (cannabidiol) and THC (tetrahydrocannabinol). 

THC is the compound that provides cannabis with its psychoactive properties, which produce the high received from using cannabis. CBD, meanwhile, provides most of the medical benefits of cannabis, without any of the mood-altering effects.

There are a number of studies and medical trials that indicate CBD has the ability to relieve pain, reduce stress and help with specific ailments. Better still, so far the evidence only points towards low-risk side effects, such as drowsiness. 

What is CBD?

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The commercial sale of cannabis is a growing industry in the USA, with many states legalizing over-the-counter sales of cannabis-based products for both recreational and medical use. However, many government departments, like the FDA, are concerned that the rapid commercialization of cannabis is outpacing both the regulations and research needed to make sure it’s safe for consumers. 

Is the FDA right to be concerned? We've investigated the CBD industry to understand its marketing practices, the depth of the medical and health research cited, and the quality of CBD products available. Here's what we found out...

The types of cannabinoids present, and the amount produced, vary across different species of cannabis plant. Hemp has low amounts of THC, roughly in the region of 0.03%, whereas marijuana has higher amounts of THC that can reach 30%. 

Because cannabis oil extracted from hemp has extremely low amounts of THC, it falls outside of the FDA regulations due to the 2018 Farm Bill. This means that CBD products that contain 0.03% THC, or less, are legal. 

Some CBD products have higher levels of THC. The status of their legality depends on an individual state’s legislation – but because almost every state has different legalization, this can be a confusing and complex issue. The FDA maintains cannabis products with a higher THC are prescription drugs, and not approved for over-the-counter purchase or recreational use. Just how legal the CBD product is might even depend on whether it's classed as a cosmetic product, food or medicine. 

CBD products legal gavel

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In general, more states are in the process of legalizing cannabis products with a higher level of THC, and the legalization of cannabis products for recreational use is a growing trend. 

To know which cannabis products are legal in your state (opens in new tab), it's best to check the local regulations – and assess this against the level of THC in the product (opens in new tab)

As the use of CBD oil exists in a grey area, the FDA is still mapping out the law and regulations in the industry through a series of public hearings (opens in new tab)

CBD: Is it too good to be true? 

Our review of the CBD industry has highlighted some worrying practices. Both the scientific health claims promoted and the goods produced raise concerns. 

Let’s start with the science. 

Many of the studies cited for the health benefits of CBD are small-scale experiments that haven’t been ‘replicated’ or ‘falsified’. These are important steps in establishing the validity of results. If results can be replicated – and previous experiments disproved – you can feel confident in the findings, and be sure you’re not wasting your money on something that doesn’t work.

There are also reports of some alarming practices in the industry. Some CBD goods marketed as “all-natural, no high” are anything but. Some of these “CBD” products have powerful synthetic cannabinoids inserted: these are man-made chemicals, and they can produce a high with unpredictable side effects, including rapid heart rate, vomiting, agitation and hallucinations. The unexpected chemical high is especially risky if you're a recovering addict and could trigger a relapse. However, there is very little long-term research available on synthetic cannabinoids, so we don’t fully know how dangerous they are yet. 

And it's not just the brand you buy: it's also about where you buy it from. Counterfeiting happens in all industries these days and CBD products are no exception.

As regulation is still lacking, you need to be extra vigilant when it comes to purchasing products advertised as containing CBD. But all that said, there are many people who extol the virtues of CBD to relieve their symptoms.

Are CBD products safe? 

The safety of CBD products depends on the method used to extract the cannabis (opens in new tab) from the hemp plant. Some manufacturers use chemical solvents to remove the cannabis oil from the plant, and this can leave behind chemicals that are dangerous when heated. This is especially dangerous when vaping cannabis oil or using it as incense. If you're going to heat a CBD product, we’d recommend you buy a CBD designed for that purpose, as it's less likely to have combustible chemicals that may cause more harm than good. 

When buying CBD oil, it's best to buy products that have gone through a C02 extraction process. This usually makes them more expensive, but they're the safest on the market – leaving no harmful chemicals behind in the process. 

The FDA also warns against using synthetic cannabinoids (opens in new tab) like Spice and K2, as the chemicals present can cause serious illness. As we've mentioned, some CBD manufacturers insert synthetic cannabinoids into products to create a high without the THC. There have been numerous reports of CBD brands caught offering 'all-natural products' that have actually been inserted with man-made highs ranging from cough syrup to rat poison. 

The legal use of CBD and cannabis-related products is also relatively new. This means there aren't many studies conducted on the long-term effects of using CBD. No one knows whether you might suffer unwanted problems after decades of regular use. 

We advise that you always check with your doctor before using CBD products. 

CBD health benefits

CBD health benefits

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There are many claims around CBD oil concerning which health conditions it can help with, prevent or even cure. Most of these claims are based on a small selection of studies that are often unreliable because the results are inconclusive, and haven’t been reproduced in other experiments. 

We’d caution against buying CBD products based on these studies, and advise you check with your doctor before using CBD oil in any medical capacity. 

CBD oil and cancer prevention

The claim that CBD products can be used to prevent cancer (opens in new tab) is based on a very small experiment conducted in 2016. There were some promising results in this study that showed CBD oil does suppress tumor growth. However, in some cases it actually increased the growth of cancer because it suppressed the immune system. The study was also undertaken on animals – meaning the results in humans could be very different. Based on this study alone, it's very unlikely that CBD prevents cancer. We’d advise you to avoid using any CBD products that make this claim. 

CBD oil and cancer pain treatment 

The use of CBD as a pain management tool is one of the areas in which there is more conclusive research. CBD has anti-inflammatory properties that can ease pain in cancer patients. This has been well documented in studies that show CBD bounds to specific receptors in the body to prevent swelling (opens in new tab) and reduce subsequent pain. Using CBD oil to reduce pain from swellings seems to be one of its major health benefits. 

CBD and pain relief from central nervous disorders

Marijuana has been documented to help ease pain from people suffering with pain from nerve disorders and damage. This is largely due to THC, which bounds to a different type of receptor than CBD (opens in new tab). Double-blind studies conducted on patients with multiple sclerosis indicated that CBD only had a slightly better reported effect than a placebo (opens in new tab). This means we’d recommend products with a higher THC level for nerve damage – in states where it's legal. 

CBD and arthritis 

There has been a wealth of studies conducted on arthritis and CBD oil, most of which finding it to help reduce the swelling and pain produced from swollen joints. The results are extremely promising, to the point that even the Arthritis foundation is happy to publish guidance on how to use CBD to relieve joint pain and inflammation (opens in new tab). The foundation advises that you start with low doses and increase them slowly over time to find the right dose for you; use CBD-only products; and use it once a day at night. 

CBD oil and anxiety 

Research suggests that CBD can aid people with anxiety problems, helping them to unwind and relax. There's a lot of evidence to support CBD usage as an anti-anxiety medication from scientific studies (opens in new tab), however a great deal of this comes from animal studies again. There are human trials, but we've failed to uncover one that uses a double-blind (opens in new tab) method of investigation, which reduces the potential of inaccuracies entering the test. 

So while there's a lot anecdotal evidence for CBD’s use in managing anxiety, without a double-blind study it's hard to tell if this is a result of the powerful placebo effect (opens in new tab) or direct results. Overall, we think there's enough evidence to suggest that CBD may help some people with the management of anxiety. 

CBD and skincare 

There are many lotions being sold on the basis of CBD helping with skin conditions like Eczema. Again, the evidence for this is based on results from very small studies conducted on rats, but the science behind the claim is solid in theory. That's because the majority of skin conditions are created from inflammation, and CBD is an anti-inflammatory. Whether this theory holds up in reality remains to be seen. 

CBD oil is also reported to have high levels of antioxidants. 

CBD and recovering addicts 

CBD is treated with great caution by a number of recovering addicts. They fear it could trigger a relapse, and associate it with their previous drug-use habits. However, there are no psychoactive properties and many recovering addicts do use CBD without it triggering addiction. 

In fact, some studies conducted on CBD as therapeutic to prevent relapses (opens in new tab) have yielded potential support, indicating that CBD can help with addiction and drug recovery, rather than causing a relapse.

We’d caution recovering addicts to follow their instincts. If you're concerned it might cause you to relapse, or trigger responses from behavioral S-R links, do not use it. But because there's no high, pure CBD products alone won’t trigger a relapse.

CBD and epilepsy

Epilepsy is the one area CBD use as a medication is officially endorsed by the FDA. The FDA has sanctioned the use of a CBD-derived drug called Epidiolex. Epidiolex is an oral solution that's used to help control the seizures produced from epilepsy (opens in new tab). There are only a small number of studies in this area, but all have been replicated with the same results. 

We recommend you only taking CBD to manage epilepsy if recommended by your doctor, and not in addition to any other kind of epilepsy medication – as there are a small number of drug interactions. These interactions can cause your medication to become less effective and toxic material to build up.

Is CBD treatment covered by Medicare?

CBD is not covered by Medicare, so your Medicare insurance (opens in new tab) won't cover the costs even if you find it works for you and helps with a health condition. This is because CBD is still not approved by the FDA. 

CBD oil for dogs

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CBD oil for dogs 

Anecdotal research regarding CBD medication for dogs looks very promising on the surface. Many dog owners report positive medical application for numerous ailments, including controlling seizures, as well as the medication of pain. 

However, there is little scientific evidence – or very few studies done – on the  effects of CBD use in dogs (opens in new tab). Possible side effects can include dry mouth, lowered blood pressure and drowsiness. 

One thing to remember when giving CBD to dogs is to change the dose of CBD according to the dog's size. Getting the dose right might be tricky, though, because there is no official guidance on what CBD dosage to give dogs due to their size (opens in new tab). The best advice we've come across is to start by giving a dog small amounts, and slowly building up the dose over time until an improvement is seen, or the dog starts to become drowsy. We always recommend consulting with your vet before giving your dog new medication. 

Should I use CBD oil? 

CBD research is still very much in its infancy. Another decade’s worth of research into CBD is needed before we can ascertain any concrete conclusions about health benefits or long-term side effects (opens in new tab)

If you're totally set on using CBD, we’d advise you to only use it occasionally – and not on a habitual basis unless prescribed by a medical professional. Some research has shown hormonal imbalances in rats while they were using CBD: if this happens in humans, it could result in long-term side-effects.

We’d also advise you to research any study used in marketing by a CBD seller. Often, the results aren't as conclusive or clear as they're stated. 

Before using any CBD product, consult your doctor. Your doctor should have the latest information on CBD, and will be able to advise you as to whether it'll be a benefit or detriment to your treatment plan. 

Richard is a writer and editor. He published his first technology related piece about a Spectrum Sinclair 128K at ten years old, when he was a runner up in a dyslexic poetry competition. He has been writing or researching in and around science and technology since – although the work is usually less lyrical. He has worked on everything from technical manuals for users to white papers and reviews.