Written by Jessica Patella, ND. In a study of 4543 persons, those with the highest intake of raw garlic had a 44% reduced risk of lung cancer.
Lung cancer is the second most common cancer in both men and women, but it is the leading cause of cancer death in the United States (1,2). Worldwide lung cancer causes 1.4 million deaths per year (18.2% of the total) (3). A recent case-controlled study found eating raw garlic more than two times per week was associated with lower rates of lung cancer (1).
Past research in the lab and in animals (in vitro and in vivo) has shown garlic has a protective effect of reducing cancer in the lungs (1, 4, 5). It is thought this could be due to the high levels of chemicals called organosulfur compounds, which are excreted in the lungs when we eat garlic (1, 6).
The current research included participants with a diagnosis of lung cancer within the past 12-months (n=1,424). Control participants were chosen from the same area and matched by gender and age (+/-5 years; n=4,543) to the lung cancer participants. All participants underwent a face-to-face interview and completed an epidemiological questionnaire, which gathered basic information about their daily lives, including a food frequency questionnaire (1).
Based on the questionnaire, the most common causes of lung cancer were found to be (in decreasing order): tobacco smoking, exposure to environmental pollution, indoor exposure to high-temperature cooking oil, frequently eating fried foods and a family history of lung cancer (1).
Overall, there was an inverse relationship between eating raw garlic and lung cancer. This means that the more raw garlic that was consumed, the lower the risk of lung cancer (1). Eating raw garlic more than two times per week was more effective (OR=0.56; 95%CI 0.44-0.72) than eating raw garlic less than two times per week (OR=0.92; 95%CI 0.79-1.08), compared to individuals who never ate garlic (1). Consumption of raw garlic less than two times per week was measured as 8.4 grams/week (about 1.5 cloves) and consumption of more than two times per week was measured as 33.4 grams/week (about 5.5 cloves) (1).
A significant association between raw garlic consumption and a lower risk of lung cancer in smokers was observed (OR=0.67; 95%CI 0.43-1.05; Ptrend=0.002 for over 30 years of smoking, Ptrend=0.046 for less than 30 years of smoking), while only a borderline association was observed in those who had never smoked (Ptrend=0.137) (1).
In conclusion, there was a correlation between consuming raw garlic and a reduced risk of lung cancer (1). This was a large population-based case controlled study, but a further investigation of how this might occur is still needed (1). This was one of the first studies in humans and the largest population-based study that is known at this point in time (1).
Source: Jin, Zi-Yi, et al. “Raw garlic consumption as a protective factor for lung cancer, a population-based case–control study in a Chinese population.” Cancer Prevention Research (2013).
© 2013 American Association for Cancer Rresearch
Posted August 20, 2013.
Jessica Patella, ND, is a naturopathic physician specializing in nutrition and homeopathic medicine and offers a holistic approach to health. She earned her ND from Southwest College of Naturopathic Medicine in Tempe, AZ, and is a member of the North Carolina Association of Naturopathic Physicians. Visit her website at www.awarenesswellness.com.
References:
- Jin Z-Y, et al. Raw Garlic Consumption as a Protective Factor for Lung Cancer, a Population-Based Case-Control Study in a Chinese Population. Cancer Prev Res 2013 6(7): 711-8.
- Lung cancer statistics. American Cancer Society.
- Parkin DM, et al. Global cancer statistics, 2002. CA Cancer J Clin 2005;55:74–108.
- Thomson M, Ali M. Garlic [allium sativum]: a review of its potential use as an anti-cancer agent. Curr Cancer Drug Targets 2003;3:67–81.
- Hong YS, et al. Effects of allyl sulfur compounds and garlic extract on the expression of bcl-2, bax, and p53 in non small cell lung cancer cell lines. Exp Mol Med 2000;32:127–34.
- Cerella C, et al. Chemical properties and mechanisms determining the anti-cancer action of garlic-derived organic sulfur compounds. Anticancer Agents Med Chem 2011;11:267–71.
