Every so often, something catches the attention of the internet and suddenly it's everywhere we look. Be it flossing (a dance craze, if this one passed you by), charcoal toothpaste (yep) or edible crickets (uh-huh), we're bombarded.

Social media, glossy mags and even the breakfast news programmes all go mad for it. Then, just as quickly as it appeared, it vanishes into the ether, consigned to an annual Facebook memory, along with the ice bucket challenge.

However, something that's seducing its way into our lives in a slower, more organic way, is CBD oil. The health benefits of this amazing compound are only just entering the mainstream, and more and more of us are starting to take notice.

With the news that Oxford University is embarking on a £10 million research programme into its potential for a wide range of medical uses, CBD is set to become much more than a passing trend.

You might already be an ardent fan of CBD oil products. If so, congrats, and welcome to MELO. You'll find everything you're looking for here. But if you're new to CBD and are vaguely aware that it's in some way related to cannabis, you might be a bit wary. So, here's our lowdown on the highs, legalities and benefits of CBD oil.

What is CBD oil and how is it different from cannabis? 

Perhaps it's better, to begin with, what CBD isn't. CBD, or cannabidiol, isn't something that will make you high. It isn't addictive and won't have any detrimental side effects on your day to day ability to function, change your state of mind or cloud your thoughts. Even though it comes from the same plant as cannabis, the cannabis Sativa plant.

Cannabis, or marijuana, on the other hand, contains a compound called THC, or tetrahydrocannabinol, as well as CBD. It's the THC that's responsible for the psychoactive properties and euphoric 'highs' of cannabis products. The higher the level of THC, the higher the high.

What about hemp?

Cannabis is produced using the buds and flowers of the female cannabis sativa plant. Conversely, CBD is usually derived from hemp, which is itself sourced from the seeds and fibrous stems of the same plant.

Hemp seeds go on to make hemp seed oil products. Hemp fibres are used to create hardwearing materials and textiles (such as ropes and sacks) and to produce CBD products such as CBD oil and foods infused with CBD oil.

CBD oil is therefore sometimes labelled 'hemp extract oil'. (Incidentally, hemp seed oil contains low levels of CBD and therefore has different health benefits.)

Can CBD be legally sold in the UK? 

CBD (and other hemp-derived products) contain very low levels of THC, typically less than 0.2%. CBD has such low concentrations of THC that it's considered 'THC free'. The sale, purchase and consumption of CBD oil products is completely legal and above-board here in the UK and across most of Europe and the US.

The sale of products containing more than 0.2% THC however, such as cannabis, is illegal in most parts of the world, including the UK.

The stems of the cannabis sativa plant naturally contain high levels of CBD. However, many farmers selectively breed their cannabis sativa plants to produce a higher level of CBD than is found in the plants used to harvest standard industrial hemp. This selective breeding also reduces the THC content further, ensuring they're non-psychoactive.

Many farmers also use organic farming methods, without the use of any pesticides. Along with selective breeding techniques, this allows for a consistent and high quality CBD product.

Those producing the same plant for cannabis purposes (legally or otherwise), generally selectively and cross breed their plants to produce strains with higher levels of THC.

The demonisation and prohibition of the entire cannabis sativa plant has a complicated history, beginning in the early 20th Century. Before then, the whole plant was used for its medicinal properties for centuries.

In the 1920s however, it was added to the UK's Dangerous Drugs Act but was still allowed to be prescribed by doctors for medical reasons. Then, in 1971 the UK's Misuse of Drugs Act saw it added as a 'controlled substance' and it became forbidden for even doctors to prescribe it.

Unsurprisingly, the production, sale and use of cannabis went underground. Which is a shame, because all this meant that the health benefits of CBD, separate from the pros and cons of cannabis, went largely unnoticed until much later.

But thankfully, here in the UK, CBD food supplements containing less than 0.2% THC can now be sold openly, as products derived from the cannabis sativa plant are no longer all grouped under the same umbrella.

That said, it's not legal to grow your own cannabis sativa plants at home, for THC or CBD use. Producers of CBD must be registered with the Home Office and be issued with an official growers' licence. You must also be a registered seller or a seller of nutritional supplements in order to sell CBD.

The reasons to take CBD oil as a daily supplement are far reaching. CBD oils help to promote a relaxed, mellow feeling, that you're totally in control of. Because CBD contains no THC, there's no risk of feeling 'stoned', just less affected by the stresses and strains of modern life and better able to unwind and sleep.

Taken regularly, CBD has also been linked with helping to alleviate conditions such as anxiety, depression, stress and chronic pain and inflammation. It's also been linked with the improvement of inflammatory skin conditions, such as acne. Research also continues into the positive effects of CBD on medical conditions such as diabetes, certain cancers and epilepsy.

Is it any wonder it's now completely legal and making it to the mainstream?