More and more often, I come across cases of nonsmokers who develop lung cancer. My attention is always drawn to news of this nature because my husband passed away at the age of 51 from brain and lung cancer. He never smoked a day in his life.

The complacency non-smokers have shared over the years is no longer a viable option. Smokers and non-smokers alike are vulnerable to a disease which is largely incurable. Among patients with lung cancer, only about 14% live five years after their diagnosis.

In the face of a disease that seems to have neither rhyme nor reason, what can we do to protect ourselves? First, assess your risk for lung cancer; then take measures to prevent the disease.

What are the risk factors for lung cancer?

Gender: Unfortunately, women seem to be more vulnerable to lung cancer. Research has shown that female smokers are more susceptible to the cancer-causing chemicals found in cigarettes. In another study, a gene linked to abnormal lung cancer cell growth was found to be more active in women than in men. It did not matter whether the women smoked or not.

A family history of lung cancer: Evidence suggests that there is a lung cancer gene which predisposes offspring to develop lung cancer. However, the evidence is far from conclusive as the situation is made difficult by the fact that offspring of smokers have been exposed to a smoking environment since childhood and would therefore have a greater risk for developing the disease.

Scarring from previous lung disease : Scarring in lungs caused by tuberculosis or other lung disease can be a risk factor for lung cancer.

Second-hand smoke: Exposure to second-hand smoke has been shown to be a definite risk factor. Your risk increases by 30 percent from daily exposure to second-hand smoke. This is probably the most significant risk factor for lung cancer in non-smokers.

Exposure to radon: Radon is an odorless gas than can seep out of the soil into buildings. Worse yet, the gas can seep from the soil into water near residential communities. Radon has been implicated as a potential cause of lung cancer.

Air pollution: Long-term occupational exposure to diesel exhaust fumes may increase lung cancer risk by 47%. Air pollution in general is a risk factor in the general population. Swedish researchers estimate that as many as 1 in 10 cases of lung cancer may be caused by air pollution in the Swedish capital city, Stockholm.

Past Cancer Treatment: Researchers in Sweden who looked at the medical records of 140,000 breast cancer patients found that there was an increase of lung cancer 5 to 20 years after breast cancer treatment. Suspicion is that radiotherapy in the chest area may have made the lungs more susceptible to the disease.

Estrogen Replacement Therapy: According to researchers at the University of Pittsburg, estrogen may fuel the growth of non small-cell lung cancer.

What preventative measures can we take?

Diet: An apple a day may keep lung cancer away. A Finnish study suggests that apples not only keep doctors away, but provide protection for the lungs as well. This study found that people who ate the most apples were 58 % less likely to develop lung cancer. Other studies suggest that lung cancer risk is lower among smokers and non smokers who ate at least 5 servings of vegetables and fruits daily.

Beta Carotene: A high intake of beta carotene compounds can lower your lung cancer risk; however, studies also show that the beta carotene is only effective when the compounds are ingested from whole foods such as peaches, melon, carrots, mangoes, dark leafy vegetables, squash etc. The opposite effect seems to take place with beta carotene supplements. A Finnish study reported 18% more lung cancer cases among heavy smokers who took beta carotene supplements. And a National Cancer Study on the effects of vitamin A and beta carotene was halted because smokers taking the supplements had 28% more lung cancer than those taking a placebo.

Selenium and Vitamin C: Taking selenium supplements on a long- term basis has been shown to decrease the incidence of lung cancer. In one study, people taking 55-200 mcg of the mineral daily had a 46% lower rate of lung cancer. As well, studies indicate that people who take less than 90 mg of vitamin C on a daily basis may have a 90% higher risk of lung cancer than those who take 140mg or more.

Avoid second-hand smoke and check your house for radon.

There are never guarantees in life, but it makes perfectly good sense to take some preventative measures as these can not only improve your overall quality of health and life but also prevent lung cancer.