Asking A Drug Expert How You Can Reduce The Harms Of Smoking Weed

Cannabis can be used to heal, but use also comes with harms. However, these harms can be minimised.

Professor Adam Winstock, founder of the Global Drugs Survey and a psychiatrist specialising in addiction, recently spoke to Simon Doherty – drug journalist and content creator – to answer questions on cannabis harm reduction.

Here’s what we learned…

1. Spliffs are the UK’s hidden nicotine gateway

In Britain, rolling up with a mix of tobacco and cannabis is so ingrained that most people don’t even question it. But Winstock doesn’t mince his words when asked whether ditching the baccy makes a difference:

“Yes. If there are two bits of harm reduction advice for people who use weed: one, don’t mix with tobacco.

“In the UK and Europe it’s like 70–80% of people mix with tobacco. You roll a joint with tobacco in New Zealand you’ll be booted out. Same in the States, Australia, Canada. It’s just a no no.”

So why do we do it? Mostly economics. A sprinkle of baccy stretches the weed further, helps it burn more evenly, and – let’s be honest – has just become habit. But the consequences are serious.

“I think nicotine does affect at a receptor level the high you get. And I think cannabis is a gateway drug. It’s a gateway drug to tobacco. For most people now the first time they’re being exposed to tobacco is when they have a spliff. That’s not a good thing.”

It means that thousands of people who might never have picked up a cigarette are being nudged toward nicotine dependence through cannabis use.

2. Holding your breath is total bollocks.

We all know someone who swears that keeping smoke in your lungs for 15–20 seconds makes the high stronger. Winstock calls this out directly:

“People think, ‘Ooh, because I’m holding the smoke in my lungs for 15, 20 seconds I’m absorbing more of the good shit.’ It’s bollocks. Most of the stuff that gets you stoned is absorbed in the first two, three seconds in your upper airways. So, you know, take [a drag]… pass a joint on.”

In other words, the ritual of “holding it” doesn’t give you more THC. It just gives your lungs more punishment.

3. Vapes and edibles are safer

For those serious about reducing harms, vaping stands out as a game-changer.

“The introduction of dry herb vapes – fantastic. If you’re someone who smokes weed at the moment and that’s your drug of choice, move to a vape.”

Vaping avoids combustion, which is where most of the carcinogens and irritants come from. The high feels different – softer, smoother, more body-based – but that’s because you’re no longer mixing with nicotine or burning plant matter.

“Mixing the spliff with nicotine is poly-drug use. Two drugs there, right? … Even if you’re just smoking weed, people will go vaping is… not [the same]. I don’t know whether it’s just the absence of tobacco, or maybe because they’re not getting the hit at the back of the throat. When you’re combusting, burning cannabis, you’re getting some other bits and pieces as opposed to when you’re just releasing the THC in an aerosol. But I think people can adapt to that.”

Edibles are another option, though they come with their own quirks. Smoking tolerance doesn’t translate to eating cannabis, which is something that still puzzles even the experts.

“Weirdly there are people who will say, ‘I can smoke half a gram of 98% THC oil in a vape and I’m fine, but give me a 10 milligram cookie and I’m completely off my face.’ … It doesn’t make sense… but people with huge tolerance for smoking can be laid waste by an average edible.”

The lesson? Respect edibles. They’re potent, unpredictable, and delayed in onset, meaning it’s easy to overdo it.

4. Driving risk

Finally, how after consuming weed should you wait to drive? It’s a question cannabis users hate but need to face.

Winstock doesn’t sugarcoat it:

“Playing it by the book, it would depend on your tolerance and your experience of driving. I think… if this was in court, I’d probably say 48 hours. In practice, I’d probably say 24, assuming you haven’t taken other drugs, you’ve slept well, and you’re not tired. I think the risk reduces a lot after 12.”

But risk reduction doesn’t mean no risk.

“Whether you like it or not, the risk of a fatal road accident after using cannabis goes up probably two, two and a half fold.”

And the danger multiplies when alcohol is involved:

“You could drink a pint, be under the drink drive limit, and then have a little puff on a joint — you’ll be massively impaired. They have a synergistic effect. That combination is dreadful.”

The message is simple: don’t drive stoned. Don’t drive tipsy. And absolutely don’t mix the two.

Final thoughts

Even if you love weed, there’s no point pretending it’s harmless. Acknowledging the risks and making smarter choices makes for a better experience. So…

• Skip the tobacco.
• Don’t hold in smoke.
• Try a dry herb vape.
• Don’t get behind the wheel soon after using.

Cannabis culture has always been full of rituals and habits – some of them helpful, others harmful. As Professor Winstock shows, small changes in how we use can make a huge difference to our health and safety.

Watch the full video here.

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