The American Cancer Society recommends the following:

The best way to reduce your risk of lung cancer is not to smoke and to avoid breathing in other people's smoke.

Radon is an important cause of lung cancer. Exposure to radon can be reduced or eliminated by having your home tested and treated, if needed.

Avoiding exposure to known cancer-causing chemicals, in the workplace and elsewhere, can also be helpful. When people work where these exposures are common, they should be kept to a minimum.

A healthy diet with lots of fruits and vegetables may also help reduce your risk of lung cancer. Some evidence suggests that a diet high in fruits and vegetables may help protect against lung cancer in both smokers and non-smokers. But any positive effect of fruits and vegetables on risk would be much less than the increased risk from smoking.

Attempts to reduce the risk of lung cancer in current or former smokers by giving them high doses of vitamins or vitamin-like drugs have not been successful so far. In fact, some studies have found that beta-carotene, a nutrient related to vitamin A, appears to increase the rate of lung cancer in these people.

Some people who get lung cancer do not have any apparent risk factors. Although we know how to prevent most lung cancers, at this time we don't know how to prevent all of them.