Lung cancer is the leading cause of cancer death for men and women in the U.S., according to the American Cancer Society. About 164,100 new cases of the disease were expected to be diagnosed in 1997 and 156,900 people were expected to die from the cancer. Smoking avoidance is the most important behavior to reduce lung cancer risk. Researchers estimate that fruit and vegetable consumption may lower risk at best two-fold, while smoking cessation causes a 20-fold decrease in risk.
Apart from smoking cessation, further reduction of risk may be achieved by weight loss (when appropriate), a healthier diet (fruits and cabbage family vegetables), and supplements such as selenium and vitamins C and E. Vitamins C and E work synergistically and a moderate dose of both taken in combination may provide more of a protective effect against lung cancer than either taken separately. Epidemiology[/glossary], 1997;146(3): pp.231- 243]
Conditions that suggest Increased Risk of Lung Cancer
Hyperparathyroidism
When hyperparathyroidism is present, the likelihood of elevated serum calcium being caused by other conditions is obviously reduced.
Risk factors for Increased Risk of Lung Cancer
Cigarette Smoke Damage
In addition to heart disease, cigarette smoking, with an increased consumption of polyunsaturated fatty acids, is the single major cause of cancer death in the United States. Cigarette smokers have total, overall cancer death rates twice that of nonsmokers. The greater the number of cigarettes smoked, the greater the risk. Smoking alone increases lung cancer risk by as much as 40 times.
Hypocalcemia or hypercalcemia or normal total calcium level
Hypercalcemia associated with malignancy, commonly is the result of breast or lung cancer and is caused by increased osteoclastic activity within the bone.
Problem Caused By Being Overweight
Researchers used data from a study of lung cancer patients in New York from 1982 to 1985. They focused on patients who had never smoked, or those who hadn’t smoked in the last 10 years, then took into account physical data on patients’ heights and weight. Researchers found that study subjects who were at the most extreme levels of obesity had the highest risk of lung cancer. The study is a first for linking being overweight to lung cancer; it has previously been shown to play a role in breast, uterine, and colon cancer.
Researchers are unsure why being obese plays a role in lung cancer; some researchers suggest it’s related to hormones such as higher levels of estrogen and insulin. In addition, being overweight puts an added strain on the lungs, reduces lung capacity, and increases asthma risk. [American Journal of Epidemiology Sept. 2000]
Selenium supplementation
History of lung cancer
Significant/severe diesel exhaust exposure
A preliminary report, still undergoing review by experts, states that “for carcinogenic hazard and risk of cancer over a lifetime, the EPA is recommending that exposure (to diesel exhaust) be viewed as likely to pose a risk at low levels, as well as high levels.” The draft report, which can be accessed at the agency’s website at www.epa.gov, is based on an overview analysis of dozens of animal- and human-based studies. It explains that the particulate matter found in diesel fumes is very small in diameter and thus able to penetrate deeply into the lungs upon inhalation. The report authors also note that “light-duty diesel engines emit 50-80 times and heavy-duty engines 100-200 times more particulate matter than catalytically equipped gasoline engines.”
Air pollution exposure
Over many years, the danger of breathing soot filled air in polluted cities is comparable to the health risks associated with long term exposure to second hand smoke, according to a new study funded by the NIH and US EPA. The study assessed the impact of particles smaller than 2.5 micrometers, called fine particulate matter, in cities across the United States. Data was gathered from 500,000 adults who were followed from 1982 to 1998 as part of an ongoing cancer study. The study concluded that a 10mcg / cubic meter increase in fine particulate matter caused an 8% increase in the number of deaths from lung cancer. [Environmental News Service March 6, 20002]
Vegetable oil consumption
Although smoking has been linked to lung cancer, the risk of developing it may be increased more by fatty acid consumption while smoking, rather than by the smoking itself. Lung cancer was not so much of a problem for smokers until polyunsaturated oils such as corn, safflower and sunflower were added to the diet during the 1950s in the United States. Even among smokers, a low fatty acid diet will reduce the likelihood of getting lung cancer.
Counter Indicators
(Lack of) vegetable oil consumption
Although smoking has been linked to lung cancer, the risk of developing it may be increased more by fatty acid consumption while smoking, rather than by the smoking itself. Lung cancer was not so much of a problem for smokers until polyunsaturated oils such as corn, safflower and sunflower were added to the diet during the 1950s in the United States. Even among smokers, a low fatty acid diet will reduce the likelihood of getting lung cancer.
Increased Risk of Lung Cancer can lead to
Recommendations for Increased Risk of Lung Cancer
Cabbage Family Vegetables
Chemicals found in broccoli, cabbage, bok choy and other cruciferous (cabbage family) vegetables may protect against lung cancer, according to a new study conducted jointly with US and Chinese researchers. Although the chemicals did lower cancer risk by 36% in this study, smoking alone increases lung cancer risk by as much as 10 times.
Vegetarian/Vegan Diet
A higher consumption of potatoes, but not leafy green or other vegetables, was associated with a reduced risk of lung cancer in a study in Spain. However, higher fruit consumption was associated with an increased risk of lung cancer. [ Nutr Cancer 2002;43(1): pp.47-51]
LDN - Low Dose Naltrexone
Although lung cancer tissue is low in opiod receptors and thus not so likely to respond to LDN, there may be benefit due to LDN’s abililty to increase natural killer cell function.
Selenium
A double-blind study demonstrated that supplementation with 200 mcg/day of selenium (in the form of high-selenium brewer’s yeast) reduced the incidence of prostate, colorectal and lung cancer, and reduced overall cancer mortality by 50%. [JAMA 1996;276: pp.1957-1963]
However, another study found that selenium supplementation was not associated with the incidence of lung and colorectal cancers. [Cancer Epidemiol Biomarkers Prev 2002;11(7): pp.630-639]
Vitamin B12 (Cobalamine)
See the link between Increased Lung Cancer Risk and folic acid.
Vitamin Folic Acid
Folic Acid and vitamin B12 work together in the body to help cells replicate normally. In a double-blind trial, smokers with precancerous changes in the lungs were given a placebo or the combination of 10,000 mcg of folic acid and 500 mcg of vitamin B12 per day for four months. A significant reversal of precancerous changes occurred in those given vitamin supplements compared with those given the placebo. [JAMA 1988;259: pp.1525-30]
Vitamin K1/K2
The European Prospective Investigation into Cancer and Nutrition – Heidelberg cohort study involving 24,340 participants aged 35 – 64. They were free of cancer at enrollment (1994-1998) were actively followed up for cancer incidence and mortality through 2008. Their vitamin K1 and K2 dietary intake was tracked over these years and compared to cancer incidence and mortality. Vitamin K2, but not vitamin K1, was inversely associated with the risk of cancer and cancer mortality. The benefit of vitamin K2 was greatest for men, with a notable reduction in prostate and lung cancer.
Vitamin E
High levels of alpha-tocopherol (a form of vitamin E) in the blood appear to reduce the risk of developing lung cancer in smokers by about 20%. The researchers attribute the decrease in cancer to vitamin E’s antioxidant properties and anticancer properties. The researchers report that the men most likely to experience a benefit from high serum levels of alpha-tocopherol included those younger than 60, men who had smoked for less than 40 years and men who took vitamin E supplements containing alpha-tocopherol during the study. [Journal of the National Cancer Institute October 20,1999;91: pp.1738-1743]
Key
| Weak or unproven link |
| Strong or generally accepted link |
| Proven definite or direct link |
| Weakly counter-indicative |
| Strongly counter-indicative |
| May do some good |
| Likely to help |
Glossary
Cancer
Refers to the various types of malignant neoplasms that contain cells growing out of control and invading adjacent tissues, which may metastasize to distant tissues.
Selenium
An essential element involved primarily in enzymes that are antioxidants. Three selenium- containing enzymes are antioxidant peroxidases and a fourth selenium-containing enzyme is involved in thyroid hormone production. The prostate contains a selenium-containing protein and semen contains relatively large amounts of selenium. Clinical studies show that selenium is important in lowering the risk of several types of cancers. In combination with Vitamin E, selenium aids the production of antibodies and helps maintain a healthy heart. It also aids in the function of the pancreas, provides elasticity to tissues and helps cells defend themselves against damage from oxidation.
Serum
The cell-free fluid of the bloodstream. It appears in a test tube after the blood clots and is often used in expressions relating to the levels of certain compounds in the blood stream.
Calcium
The body's most abundant mineral. Its primary function is to help build and maintain bones and teeth. Calcium is also important to heart health, nerves, muscles and skin. Calcium helps control blood acid-alkaline balance, plays a role in cell division, muscle growth and iron utilization, activates certain enzymes, and helps transport nutrients through cell membranes. Calcium also forms a cellular cement called ground substance that helps hold cells and tissues together.
Polyunsaturated
Polyunsaturated fats or oils. Originate from vegetables and are liquid at room temperature. These oils are a good source of the unsaturated fatty acids. They include flaxseed with added vitamin B6 (pyridoxine), sunflower oil, safflower oil, and primrose oil.
Fatty Acids
Chemical chains of carbon, hydrogen, and oxygen atoms that are part of a fat (lipid) and are the major component of triglycerides. Depending on the number and arrangement of these atoms, fatty acids are classified as either saturated, polyunsaturated, or monounsaturated. They are nutritional substances found in nature which include cholesterol, prostaglandins, and stearic, palmitic, linoleic, linolenic, eicosapentanoic (EPA), and decohexanoic acids. Important nutritional lipids include lecithin, choline, gamma-linoleic acid, and inositol.
Hypercalcemia
Excess calcium in the blood.
Colon
The part of the large intestine that extends to the rectum. The colon takes the contents of the small intestine, moving them to the rectum by contracting.
Hormones
Chemical substances secreted by a variety of body organs that are carried by the bloodstream and usually influence cells some distance from the source of production. Hormones signal certain enzymes to perform their functions and, in this way, regulate such body functions as blood sugar levels, insulin levels, the menstrual cycle, and growth. These can be prescription, over-the-counter, synthetic or natural agents. Examples include adrenal hormones such as corticosteroids and aldosterone; glucagon, growth hormone, insulin, testosterone, estrogens, progestins, progesterone, DHEA, melatonin, and thyroid hormones such as thyroxine and calcitonin.
Estrogen
One of the female sex hormones produced by the ovaries.
Insulin
A hormone secreted by the pancreas in response to elevated blood glucose levels. Insulin stimulates the liver, muscles, and fat cells to remove glucose from the blood for use or storage.
Asthma
A lung disorder marked by attacks of breathing difficulty, wheezing, coughing, and thick mucus coming from the lungs. The episodes may be triggered by breathing foreign substances (allergens) or pollutants, infection, vigorous exercise, or emotional stress.
Epidemiology
The study of the causes and distribution of disease in human populations.
Carcinogen
Any agent that is cancer-causing.
EPA
Environmental Protection Agency. Also: Eicosapentanoic Acid. A metabolite of the omega-3 fatty acid alpha-linolenic acid.
Microgram
(mcg): 1/1,000 of a milligram in weight.