Smoking and Lung Cancer

By Richard Dowson

According the Government of Canada Website, “Tobacco and lung cancer”, Lung Cancer is “… the uncontrolled growth of cells in the lung or airways, leading to the formation of a tumour.”

The Canadian Government site, “Tobacco and lung cancer” states;

“An estimated 72% of lung cancer cases in Canada are caused by smoking.”

(It is believed the other 28% may be caused by a virus and/or environmental factors.)

Tobacco and Lund Cancer Website:

1 People who smoke are 25 times more likely to die from lung cancer

2 This risk increases sharply with the number of cigarettes smoked, the number of years spent smoking

3 In 2022, it was estimated there would be … 20,700 deaths from lung cancer in Canada, accounting for 24.3% of deaths due to cancer

4 Quitting is the most important thing someone who smokes can do to improve their health

Did people always know about the dangers of smoking?

No.​It wasn’t until 1964, in the United States Surgeon General’s Report, that the link between lung cancer and smoking was officially recognized,

Were the Dangers of Smoking known before the 1964 Surgeon General’s Report?

Yes. ​In his 2013 article, “The history of the discovery of the cigarette–lung cancer link…”, Dr Robert N Proctor, History Department, Stanford University, wrote:

1 “Cigarettes were recognised as the cause of the epidemic in the 1940s and 1950s, with the confluence of studies from epidemiology, animal experiments, cellular pathology and chemical analytics.

2 “As late as 1960 only one-third of all US doctors believed that the case against cigarettes had been established.”

Prior to 1900 and before the increase in smoking, lung cancer was rare.

In their 1951 study, British epidemiologists Richard Doll and Austin Bradford Hill linked smoking to lung cancer.

Anna Wagstaff’s article, The ‘smoking gun’: the studies that proved tobacco was the culprit behind the rapid rise in lung cancers in ‘Cancer Epidemiology’ (January 2025) notes that early discoveries were dismissed; that the medical world was skeptical of the smoking-lung cancer findings.

Wagstaff writes that the studies “… did not meet all of Koch’s criteria for causality…”.

Who is Koch?

In 1884 Robert Koch and Fredrich Loeffler developed Four Postulates for identifying a disease. The first of Koch’s criteria for causality was most often used to dismiss research into smoking and lung cancer. The postulate is: “The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy organisms.”

Koch, himself, eventually dismissed this causality ‘postulate’ as too broad and also because research showed many people suffering a disease were asymptomatic. They were ‘infected’ but showed no signs of the infection. For example, some people whosmoked, didn’t have lung cancer.

Unfortunately, this Koch Postulate was often used to dismiss other medical research.

Robert N. Proctor wrote, “The cigarette is the deadliest artefactin the history of human civilisation.” (Above Reference)

Writer Richard Dowson is a retired educator.

He is known for his frequenting local coffee shops and other places seniors gather.

In a previous life he wrote comedy for CHED in Edmonton.

As usual all views are that of the writer and may or may not reflect the views of MJ Independent