Person lighting a cigarette

The Double Whammy of Tobacco and Cannabis

This is a sample from our ‘Quit Cigarettes’ mission, which is currently live in the UK. Our goal is to increase the amount of people in the UK who quit cigarettes. Read more about our first mission here.

From DNA changes to the blues: You risk getting more than you bargained for when you skin up. The explanation is in the mix.

They’re two of the most-used drugs in the world, and they have an almost unique relationship. If you’re a cannabis user then there’s a 90 percent chance you’ll be a tobacco smoker too.

The reason for this is practical as much as anything. Although you can smoke marijuana on its own or ingest the resin, many people prefer mixing cannabis leaf or resin combined with tobacco in a joint. Unfortunately, tobacco and cannabis smoke both contain harmful chemicals, including mutagens. These can lead to changes in DNA, which can cause cancer, which are absorbed when inhaled.

THC Increases Nicotine Craving

But this may not be the whole story. Some studies suggest that pot smoking makes you more likely to become addicted to nicotine. However, because the study was conducted in mice, it’s not clear whether the findings translate to people. Some animal studies have shown that exposure to THC (Tetrahydrocannabinol) – the substance in marijuana that creates the ‘high’ – makes someone more likely to have an enhanced response to other addictive substances, such as morphine or nicotine.

Studies suggest that pot smoking makes you more likely to become addicted to nicotine

Unfortunately for people who combine use of marijuana and tobacco, there is evidence that the two together can create a double whammy effect on health. In particular, the structure in the brain called the hippocampus, which deals with memory, can become a lot smaller over time if someone smokes tobacco and cannabis combined.

Poorer Memory

Although individual use of either substance on their own is linked to a smaller hippocampus, using both together results in lowest hippocampus volumes. A study published in the October 2015 issue of Behavioural Brain Research found that tobacco and marijuana users had smaller hippocampus structures than people who stuck to one or other but not both. The researchers said there was a complex interactions between marijuana and nicotine which needed more investigation. A newer study, published in 2017, did find that cigarette smokers lost more hippocampus volume and this might explain why other studies have shown smokers have memory impairment.

Users can feel tired and sometimes depressed

And both drugs have profound impact on your body apart from releasing dopamine in the pleasure and motivation area of the brain. Research has found that taking marijuana on its own can raise the heart rate by between 20 and 100 percent for up to three hours. Research also indicates that use raises the heart rate by 20-100 percent shortly after smoking; this effect can last up to three hours.

When THC levels start to drop, users can feel tired and sometimes depressed. Nicotine can also push up blood pressure, heart rate and breathing rate because it causes your body to release more of the hormone epinephrine which is the ‘fight or flight’ hormone.

I was Failing at Exams

Josh (not his real name) is 25 years old and lives in Surrey. He started using cannabis at school and says he began smoking at "pretty much the same time". It was partly because of circumstances: "we couldn’t always get hold of the cannabis so smoking straight cigarettes was like an easy alternative. I hated smoking at first of course but once I got used to it, it was fine" he says.

He says he stopped smoking pot, and quit cigarettes for good, when his exam results started to suffer. He was also suffering from racing heart which could last for hours. "I had heard about memory loss linked to smoking joints and I was worried that it would happen to me. It was really hard to quit because I really craved the high. But my memory did start to improve after several months of not smoking joints and my heart stopped pounding which was a big relief."

Head photo by Joseph Ngabo