These are the five most addictive drugs in the world

These are the five most addictive drugs in the world

While many don't openly talk about it, especially when it comes to family, there are plenty of people out there indulging in recreational drug use. Whether it's a joint after a stressful day of work or lines of coke before a Saturday night out - odds are there are plenty of people you meet each day that are spending their time and money on this sort of thing.

But what are the most addictive substances? We are often warned about the addictive qualities of hard drugs from a young age, but what exactly does science say?

A group of addiction experts got together to figure this out. Chemists, forensic scientists, and pharmacologists analyzed the addictive qualities of various drugs, ranking them to see which five substances topped the list. The group was headed by Professor David Nutt, who works in neuropsychopharmacology at Imperial College London, and is one of the world's best experts on drugs in terms of their effects on the human brain and international drug policy.

The research team looked at three factors: the pleasure given by use, psychological dependence, and physical dependence. They ranked each drug from zero to three, with zero being the least addictive and three being the most addictive. So what topped the list?

Unsurprisingly, it was Heroin that was number one on the list, with a score of 3 out of 3. Following close behind with 2.4 was Cocaine, but here's where things get interesting. The third, fourth and fifth entries into the list are actually legal to purchase unlike the first two.

Nicotine came in at number three with a score of 2.2, and Barbiturates (which are often prescribed to treat seizures and anxiety) had a score of 2. At the end of the list, unfortunately, is alcohol - a commonly-consumed substance that got a score of 1.9 out of 3.

Despite the fact it is likely the most socially acceptable recreational drug, alcohol is actually far more dangerous than many of us know - The World Health Organisation even estimated that around 5.9% deaths worldwide are attributable to alcohol consumption.

Professor Nutt also wrote a paper on the harmfulness of various drugs available in the UK, both illegal and legal. The 2010 study looked at various drugs and their direct and individual effects on the user and others around them. They considered everything from death rates, dependence, criminal activity and financial losses to the damage and cost to the country.

From these tests, which were confirmed by further tests at a European level, it turned out that alcohol was the most dangerous out of all them. Heroin and crack cocaine were next on the list, tobacco was 6th, and cannabis was 8th.

"There are two elements to it," Nutt said. "Deciding on the various harms – the 16 parameters – most experts agree on that. The more interesting question is how much you care about each of these different rankings; this is where the weightings come in. This could vary greatly depending on the group’s opinions."

Seeing as even the legal and most commonly-used drugs out there, such as tobacco and alcohol, can still be incredibly addictive and dangerous - it's worth keeping things in moderation, giving it more thought than you might have before.