Lung cancer is a malignancy of the lung. It is characterized by unregulated replication of cells creating tumors, with the possibility of some of the cells spreading to other sites (metastasis).
This article includes a discussion of studies that have assessed whether certain vitamins, minerals, herbs, or other dietary ingredients offered in dietary or herbal supplements may be beneficial in connection with the reduction of risk of developing lung cancer, or of signs and symptoms in people who have this condition.
This information is provided solely to aid consumers in discussing supplements with their healthcare providers. It is not advised, nor is this information intended to advocate, promote, or encourage self prescription of these supplements for cancer risk reduction or treatment. Furthermore, none of this information should be misconstrued to suggest that dietary or herbal supplements can or should be used in place of conventional anticancer approaches or treatments.
It should be noted that certain studies referenced below, indicating the potential usefulness of a particular dietary ingredient or dietary or herbal supplement in connection with the reduction of risk of lung cancer, are preliminary evidence only. Some studies suggest an association between high blood or dietary levels of a particular dietary ingredient with a reduced risk of developing lung cancer. Even if such an association were established, this does not mean that dietary supplements containing large amounts of the dietary ingredient will necessarily have a cancer risk reduction effect.
Cancer of the lung is the leading cause of death from cancer in both men and women in the United States. Cigarette smoking is by far the most important risk factor for the development of lung cancer. Air pollution is another risk factor. A previous diagnosis of tuberculosis increases the risk of lung cancer by 5 to 10%.
What are the symptoms of lung cancer?
In its early stages, lung cancer usually causes no symptoms. As a result, lung cancer is generally not diagnosed until the disease is relatively advanced. At the time of diagnosis, common symptoms of lung cancer are similar to those of some other respiratory diseases: cough, blood stained sputum, wheezing, and shortness of breath. Lung cancer is sometimes diagnosed from a chest x-ray done for another condition. Pneumonia lasting more than two months may indicate the presence of lung cancer and should be followed-up with further testing. Later symptoms of lung cancer generally result from spread to other parts of the body (metastasis). These symptoms may include chest or shoulder pain, unexplained weight loss, bone pain, hoarseness, headaches, seizures and swelling of the face or neck. Lung cancer is usually a fatal disease, except for the minority of patients diagnosed at the early stages of the disease.
Dietary changes that may be helpful for lung cancer
The following dietary changes have been studied in connection with lung cancer.
Fruits and vegetables
Flavonoids are found in virtually all fruits and vegetables. Onions and apples contain large amounts of a flavonoid called quercetin. Consumption of flavonoids in general, or quercetin-containing foods in particular, has been associated with a reduced risk of lung cancer in some preliminary reports,2 3 although not every study finds an association between flavonoid consumption and a reduced risk of cancer.4
Researchers agree that people who eat yellow and orange fruits and vegetables—good sources of alpha-carotene and beta-carotene—are at lower risk for lung cancer. However, double-blind trials have shown that when nonsmokers supplement with (synthetic) beta-carotene, their risk of lung cancer is not reduced, and when smokers take (synthetic) beta-carotene supplements, their risk of lung cancer increases. These findings suggest that beta-carotene may not be the cause of the low lung cancer risk found in people who eat carotene-rich foods.
A review of published research found that higher intake of tomatoes or higher blood levels of lycopene correlated with a reduced risk of cancer in 57 of 72 studies. Findings in 35 of these studies were statistically significant.7 Evidence of a protective effect for tomato consumption was strongest for several cancers including lung cancer.
Avoidance of meat and saturated fat
Incidence of lung cancer correlates with dietary fat intake from country to country.11 Some,12 but not all,13 preliminary studies report consumption of saturated fat in both meat and dairy fat correlates with the risk of lung cancer, even among nonsmokers.14 Lung cancer risk appears directly related to consumption of foods containing saturated fat––not only from consumption of well-cooked meat.15 In one trial that was unable to find an association between lung cancer risk and total saturated fat intake, people consuming skim milk nonetheless had a 50% reduction in risk compared with people drinking whole-fat milk.16
Avoidance of dietary cholesterol
Avoidance of sugar
Lifestyle changes that may be helpful for lung cancer
The following lifestyle changes have been studied in connection with lung cancer.
Other inhalant pollution
Radon exposure has been reported to contribute to the risk of lung cancer in the general population.27 Radon, a natural radioactive substance, can leak into basements from the surrounding soil. Radon exposure can also occur from the water system of houses, particularly when people take showers. Underground miners are also exposed to varying amounts of radioactivity from radon.
Nutritional supplements that may be helpful for lung cancer
Folic acid and vitamin B12
The researchers who conducted the lung cancer trials have been criticized for not having used the natural form of beta-carotene.33 Preliminary evidence suggests that natural beta-carotene supplementation results in better antioxidant activity34 and anticancer activity in humans35 than does supplementation with synthetic beta-carotene. Nonetheless, much less is known about natural beta-carotene and questions remain about its potential efficacy.36 The effect of natural beta-carotene supplementation on lung cancer risk has yet to be studied.
The strong association between increased intake of beta-carotene from food and a reduced risk of lung cancer37 does not necessarily mean that supplementation with natural beta-carotene supplements would reduce the risk of lung cancer. Dietary beta-carotene may be a marker for diets high in certain fruits and vegetables that contain other anticancer substances that may be responsible for the protective effects. Until more is known, some doctors advise smokers to avoid all forms of beta-carotene supplementation—even natural beta-carotene.
The strongest evidence supporting the anticancer effects of selenium supplementation comes from a double-blind trial of 1,312 Americans with a history of skin cancer who were treated with 200 mcg of yeast-based selenium per day or a placebo for 4.5 years and then followed for an additional two years.53 Although no decrease in skin cancers occurred, a 50% reduction in overall cancer deaths and a 37% reduction in total cancer incidence was observed. A 46% decrease in lung cancer incidence and a 53% drop in deaths from lung cancer also occurred. These findings were all statistically significant.
However, the vast majority of lung cancer patients are diagnosed when the disease is more advanced than stage I. In a trial studying patients with more advanced disease, supplementation with 300,000 IU per day for one year followed by 150,000 IU per day for another year did not reduce lung cancer recurrences.60 Moreover, another trial that studied smokers and workers exposed to asbestos found that daily supplementation with 25,000 IU of vitamin A plus 50,000 IU of synthetic beta-carotene (which can act as a vitamin A precursor in the body) for four years led to a slight increase in the risk of getting lung cancer compared to no treatment.61
These studies suggest that vitamin A supplementation is unlikely to either prevent lung cancer or effectively treat lung cancer patients.
In patients with advanced lung cancer who were given 10 mg of melatonin at night in cycles of three weeks on followed by one week off, survival time was almost twice as long as survival in those not given melatonin—a statistically significant increase.75 Melatonin supplementation was not helpful to patients whose cancer had spread to the liver.76
Coenzyme Q10 supplementation
Vitamin supplement use in general
Are there any side effects or interactions with lung cancer?
Refer to the individual supplement for information about any side effects or interactions.
Herbs that may be helpful for lung cancer
The following herbs have been studied in connection with lung cancer.
Cloud mushroom (Coriolus versicolor)
Asian ginseng (Panax ginseng)
Green Tea and Black Tea (Camellia sinensis)
Dr. Sun’s Soup
Ingredients are listed in order from most to least amount present:
One small preliminary trial found that 6 of 15 people with a variety of mostly advanced cancers who attended the Bio-Medical Center and took the Hoxsey formula claimed to be disease-free after a follow-up period of five years, including two lung cancer patients.101 Average survival was surprisingly long, even for those who did eventually succumb to their cancers.102 Several of these patients appeared to have had a poor chance of survival before taking the Hoxsey formula. Larger, double-blind trials are needed to confirm or contradict these findings. Until it is confirmed in other trials, the Hoxsey formula should be considered unproven.
Limited evidence suggests that some of the components of the Hoxsey formula may have anticancer activity. In animal and/or test tube research, burdock root,103 104 berberine (a constituent of barberry),105 106 a protein found in poke root,107 108 109 110 licorice,111 112 stillingia,113 and red clover,114 have all been found to have anticancer activity. Constituents of alder buckthorn, cascara, and prickly ash bark have produced mixed results in preliminary testing investigating anticancer actions.115 116 117 118
Besides the small trial of cancer patients discussed above, no other human trials have studied the Hoxsey formula. The assertion by the American Cancer Society that the Hoxsey formula has been “extensively tested” and “found to be . . . useless”119 is therefore false.
The original Hoxsey formula is prepared as a water extract and is available only at the Bio-Medical Center in Tijuana, Mexico.120 Other versions of Hoxsey-like formulas are available, primarily from herbal companies that supply physicians. However, most of these are alcohol extracts (tinctures). Although these products may contain extracts from the same herbs, it is unknown whether these products have the same effects as does the original Hoxsey formula.
Cancer patients who attend the Bio-Medical Center in Mexico also are told to make several dietary changes and to take several supplements.121 No scientific evidence supports the use of these dietary changes or supplements in the treatment of people with cancer.
Are there any side effects or interactions with lung cancer?
Refer to the individual herb for information about any side effects or interactions.