Lung cancerPatient friendly summary
- People who work outside often have a lower risk of lung cancer. This may be due to increased ultraviolet-B (UVB) light and more vitamin D production.
- Vitamin D may lower the risk of lung cancer and improve survival rates if lung cancer develops.
Lung cancer is a cancer starting in the lungs.
Lung cancer is the leading cause of cancer death in the United States. Annually, it affects approximately 220,000 and kills about 157,000.
The primary risk factor for lung cancer is:
Other risk factors include:
- Air pollution (coal-fired power plants, diesel-fueled vehicles, wood fires, industrial chemicals, and smoke)
- Indoor cooking fires (especially in China)
- Asbestos fibers (industrial sites such as shipbuilding and manufacturers of brake linings)
- Radon (radioactive element that escapes from the ground into homes)
- Dietary fat may be a risk factor.
The risk of lung cancer may be lowered by calcium. This mineral can be added by diet (green leafy vegetables or milk) or supplements.
Sunlight exposure and lung cancer risk
According to studies, an increase in solar ultraviolet-B (UVB) light lowers the rate of lung cancer and resultant deaths:
- Three studies found a lower risk of lung cancer in those living at higher elevations. UVB light is stronger at higher altitudes.
- Farmers have a much lower incidence of lung cancer and less resultant deaths than the general population. Farmers work outside and get a lot of UVB light.
- Geographical studies of populations often found those living in regions with higher solar UVB levels had lower rates of lung cancer.
Vitamin D and lung cancer
Vitamin D levels
There are no reported studies researching a possible link between vitamin D levels and the incidence of lung cancer.
Two studies in Europe found higher 1- to 2-year survival rates for those diagnosed with lung cancer in the summer compared to diagnosis in winter. Higher vitamin D levels in the summer may account for this finding. This is also true for several other types of cancer.
How vitamin D works
Vitamin D has been shown to block the growth of cancer tumors. The active form of vitamin D, calcitriol, provides numerous benefits against cancer. This form of vitamin D encourages cells to either adapt to their organ or commit apoptosis (cell suicide). Calcitriol also limits blood supply to the tumor and reduces the spread of cancer.
Based studies of breast and colorectal cancer and some evidence regarding lung cancer, it appears that lifetime vitamin D levels above 40 ng/mL (100 nmol/L) may reduce the risk lung cancer.
Vitamin D and calcium
Obtaining vitamin D from sunlight and/or supplements and increasing calcium intake may reduce the risk of lung cancer.
A number of studies have connected lung cancer survival rates with vitamin D blood levels, seasons, and vitamin D plus calcium intake. These studies strongly suggest that vitamin D can play an important role in improving prognosis of those diagnosed with lung cancer. However, more studies are required to confirm these findings.
People with early stage non-small cell lung cancer and high vitamin D levels had better survival outcomes. However, no effect of higher vitamin D levels was seen for people with advanced non-small cell lung cancer.
Find out more...
Do you want to find out more and see the research upon which this summary is based? Read our detailed evidence summary on lung cancer.
Page last edited: 05 August 2011