Scientific Evidence Portal
Diet as a potential major confounder of the relationship between ETS exposure and lung cancer risk in non-smokers | P. N. Lee
Article Published: 1994/02/21
Further Information Statistical frauds and hysteria on obesity aside, diet is important for all of us. A good diet where all is eaten in moderation and with balance can be said to be a probable key to a healthy life without false guarantees of health.
When extremely weak associations (such as that between lung cancer and passive smoking) are guessed, what is the role of confounders such as diet? Extremely important to say the least.
Already in 1994 P.N. Lee’s meta-analysis strongly indicated that, for non smokers, diet plays a far more important role than exposure to passive smoking in the development of lung cancer, and detailed reasons and data analysis of many studies is provided in these notes.
Already, however, “public health” had quite different political programs than that of public health, and these observations were (and are) ignored. To push smoking bans and pharmaceutical cessation products, “public health” had and has to convince people that, if it were not for ETS, non-smokers would not get lung cancer at all, thus smoking has to be eliminated — and confounders ignored. In that way, another terrible disservice is done to public health, let alone to freedom of choice, self-determination, and lifestyle.
Nevertheless – and after reading this analysis – it is clear that the points highlighted are inescapable and that diet – not exposure to passive smoking – is the main driver of lung cancer in non-smokers.
There is strong evidence that various aspects of diet are associated with an increased risk of cancer of a wide range of sites, including of the lung.
Evidence has recently accumulated that diet is an important risk factor for lung cancer specifically in non-smokers.
There is strong evidence that smokers differ markedly from non-smokers in their diet, and that these differences tend to be in a direction that would predict a higher risk of lung cancer.
Evidence is accumulating that, just as smokers have poorer diets than non-smokers, so do ETS-exposed non-smokers have poorer diets than non-ETS-exposed non-smokers.
The association between ETS and lung cancer is weak.
Few studies of ETS and lung cancer have taken the possibility of confounding by diet into account.
Though confounding by diet has not yet been shown directly to be important in ETS/lung- cancer studies, there is strong indirect evidence that it is.
Unless proper adjustment for dietary differences is conducted, reports of an association between ETS and lung cancer are uninterpretable.