Dr Ian Walker on Smoking: ‘The killer behind the counter’

The link between smoking and cancer was first established over 60 years ago. Some of those early studies have been further validated across years of research. 

We now know that cigarette smoke contains over 5000 different chemicals, of which we know at least 70 are carcinogenic. This toxic cocktail of chemicals has huge impact on the health of people exposed to tobacco smoke.  

Smoking is linked to at least 15 different cancers, as well as many other medical problems, including heart disease, respiratory disorders and fertility issues.  

But what is so different about cigarettes?   

There are many things we that we know are risk factors for cancer – such as obesity, UV radiation and alcohol.

Why are cigarettes any more dangerous?  

Well, cigarettes are a uniquely toxic cause of cancer. They are a targeted consumer item that, if used exactly as intended by the manufacturer, will ultimately kill two thirds of people who use them if they don’t stop smoking. Yes, really.  

In fact, smoking causes an estimated 125,000 deaths each year in the UK – around a fifth of all deaths from all causes.  

The science behind this is clear and indisputable. World-leading researchers from across the globe have spent decades identifying the different ways that smoking tobacco can cause cancer.  

One such example, is the chemical called Benzo[a]pyrene (BP), which is created when tobacco is burned and then inhaled into the lungs. This compound causes damage to the DNA within cells and generates mutations which can lead to many different types of cancer.  

In addition to these direct DNA mutations, many carcinogenic chemicals in tobacco cause DNA to behave abnormally. This can disrupt the usual replication of a cell, which again can lead to the development of cancer.  

So, we know that tobacco is chemically dangerous for our physical health. But its danger also lies in the way it is sold as a consumer product. The business model is based on addiction. This addiction is caused by nicotine, a chemical in tobacco, which is easily absorbed via the lungs and into the blood. 

After it’s in the blood, it is distributed around the body and causes the release of dopamine in the brain. This is the body’s “reward’ mechanism, and our brains are wired to want more. Very soon, we have the desire for another reward and then another, until we can’t function normally without it.  

Nicotine is very addictive, but despite this, you can simply nip to your local corner shop to buy a 20 pack. 

We know that most who smoke become addicted to cigarettes when they are younger. In fact, nearly all those who smoke, start smoking before the age of 21, become addicted and then spend many years trying and failing to stop.  

The problems that smoking will cause for people can seem so distant, and once a physical addiction has taken hold, these reasons alone are often not enough to stop.  

In fact, we know that most people who smoke want to quit, but they need support to do it successfully. This is on top of social inequalities and barriers beyond people’s control which can impact someone’s likelihood to start smoking, and their ability to stop.  

But the sad truth is that for most people who smoke, the effects of their addiction will eventually catch up with them.  

Indeed, my grandfather fits this story exactly. He became addicted to smoking as a child in Ukraine, before emigrating to the UK after the Second World War.  

He smoked almost all his life and paid the ultimate price because of the addiction he developed as a child, when he died from cancer. This impact was felt widely across my family and represents just one of the estimated 9 million deaths caused by smoking since the 1960s in the UK.  

This may seem like a hopeless cycle, but we have the research to prove that there is a way out of it.  

Brave political leadership today, could prevent tens of thousands of cancer deaths from tobacco each year, and help to remove this terrible burden from the next generation. We could realistically see the day when none of our children become addicted to smoking – a legacy that any Government could be proud of. I’ll be explaining just how vital this action is in next week’s article.  

Ian Walker is executive director of policy, information and communications at Cancer Research UK