Reducing the Risk of Lung Cancer

Is it Possible to Lower The Risk of Lung Cancer?

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Globally, cigarette smoking is killing people by the millions every single year.

In the U.S. alone, tobacco-related deaths are close to 440,000 annually. Of those, approximately 160,000 are attributable to lung cancer, accounting for 27 percent of all cancer deaths annually.

Lung cancer kills more men and women than any other form of cancer in the U.S. today, with over 80 and 90 percent of cases for men and women respectively being directly linked to smoking.

Clearly, smoking cessation is a person’s best chance for reducing the risk of lung cancer. Health benefits begin within 20 minutes of quitting, with improvements continuing for years.

Along with a reduced risk of lung cancer, quitting lowers the risk of heart disease and chronic obstructive pulmonary disease, which includes emphysema. The sad truth, however, is that not everyone is able to quit smoking.

Two  studies appearing in the September 28, 2005 issue of JAMA indicate there are actions people can take to lower their risk of lung cancer.

The first study by Godtfredsen et al  looks at the potential for reducing the risk of lung cancer through smoking reduction, rather than smoking cessation. The authors emphasize the fact that while quitting smoking should always be encouraged as the best possible choice for smokers, reducing the number of cigarettes smoked does appear to lower lung cancer risk.

Smoking Reduction Study

This observational population-based cohort study involving 11,151 men and 8563 women was divided into 6 groups according to smoking habit:

  • continued heavy smokers (15 cigarettes or more per day)
  • reducers (reduced by a minimum of 50 percent from 15 or more cigarettes per day without quitting)
  • continued light smokers (1-14 cigarettes per day)
  • quitters(stopped between first and second examination)
  • stable ex-smokers
  • never smokers

All participants underwent physical examinations and completed questionnaires about lifestyle habits. Study participants were watched over a period of up to 31 years by the Copenhagen Centre for Prospective Population Studies.


Smokers who cut back from roughly 20 cigarettes per day to 10 or less per day do appeared to lower their relative risk of lung cancer by 27 percent, compared with continued heavy smoking.

Of note is a factor that inhibits risk reduction, known as “compensatory smoking”. People who reduce the number of cigarettes smoked sometimes draw more puffs out of each cigarette, looking for the maximum effect. Risk reduction might be greater if not for this.

Further, according to the authors, "Participants who were continued light smokers or who quit smoking between baseline and follow-up reduced their lung cancer risk by 56 percent and 50 percent, respectively, compared with persistent heavy smokers.

"Risk of lung cancer among the stable ex-smokers was 83 percent lower than among the heavy smokers, but still significantly higher than among the never smokers."

The second study, by Schabath et al, looked at the effect a diet rich with phytoestrogens has on lung cancer risk reduction.

Phytoestrogens are plant-based chemicals that are similar in nature to the female hormone estrogen. They have numerous health benefits, and act as antioxidants and tumor suppressors. These plant chemicals are found in grains and a variety of fruits and vegetables.

Phytoestrogen Study

This ongoing case-control study consists of 1674 lung cancer patients and 1735 matched healthy controls. Participants were interviewed between July 1995 and October 2003 regarding eating habits and other demographic information in an effort to guage dietary intake of phytoestrogens.


People eating the most phytoestrogens appeared to reap benefits of up to a 46 percent reduction of lung cancer. These advantages were observed in current smokers, but less so in former smokers. Those who had never smoked appeared to see the most benefit from high phytoestrogen intake, further reducing an already low risk of contracting lung cancer.


Indications are that significantly reducing the number of cigarettes smoked and eating a diet with plenty of phytoestrogen-rich foods may reduce lung cancer risk. It is important to note however, that these measures do not reduce a smoker's risk of other forms of smoking-related illnesses such as heart disease and emphysema.

Make no mistake. Smoking cessation completely is still your best option. Smoking is destructive and deadly. With over 7000 chemicals in cigarettes, many of them toxic, the effects on our bodies over time are catastrophic.


American Cancer Society. What are the Key Statistics About Lung Cancer? Accessed January 2015.

Godtfredsen NS, Prescott E, Osler M. Effect of smoking reduction on lung cancer risk. JAMA 2005;294:1493-1504

Schabath MB, Hernandez LM, Wu X, Pillow PC, Spitz MR. Dietary hytoestrogens and lung cancer risk. JAMA. 2005;294:1493-1504

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