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Non-Smokers and Lung Cancer
Lung cancer is a common type of cancer primarily linked to cigarette smoking (Schabath & Cote, 2019). Men have higher rates of lung cancer than women because of greater usage of smoking products (Schabath & Cote, 2019). There are two categories of lung cancer, non-small cell or small cell lung cancer (LoPiccolo et al., 2024). These differences depend on appearances under the microscope, and can affect disease progression (Robinson, 2022). For example, small cell lung cancer cells are rounder and more pronounced (Robinson, 2022). This type of lung cancer is more aggressive and likelier to spread to other areas of the body (Robinson, 2022).
Tobacco smoking causes 80% of cancer cases in the United States (LoPiccolo et al., 2024). Despite this, >30% of Hispanic and >55% of Asian female lung cancer patients identified as non-smokers. Lung cancer among non-smokers is the fifth most common cause of cancer worldwide (LoPiccolo et al., 2024). Women make up a disproportionate two-thirds of these cases (LoPiccolo et al., 2024). In particular, Asian women comprised the largest non-smoking group affected by lung cancer, regardless of geographic location (LoPiccolo et al., 2024). Several factors contribute to the disparity but one is rather unexpected: cooking oil.
The Problem with Cooking Oil
Several studies show that long-term exposure to cooking oil fumes may lead to lung cancer (Chen et al., 2020). Chen et al. (2020) performed a study on the Han Chinese ethnic group. Results showed that 79-86% of male lung cancer patients used tobacco. Yet, only 9-10% of female patients used tobacco. Nearly 90% of non-smoking females regularly cooked traditional family meals. This often involved heating oils until temperatures reached the smoke point and released fumes. Heating oil can release fumes containing various carcinogens, which increases the risk of inflammation, DNA damage, and cell death. This makes it a strong risk factor for lung cancer and chronic bronchitis (Chen et al., 2020).
Figure 1. This graph depicts the odd ratios for lung cancer based on cooking time-years (Chen et al., 2020). Odd ratios refer to the likelihood of getting lung cancer compared to someone with no cooking exposure. For example, an odd-ratio of “2” means someone is two times likelier to get lung cancer than a non-exposed person. A cooking-time year of “1” corresponds to no cooking time and “5” to extensive cooking time. The graph shows an increase in lung cancer risk with increased cooking exposure.
What Can We Do?
You might be wondering, how can we lower exposure to cooking fumes? After all, everyone deals with cooking oil fumes in the kitchen. Vegetable oil can be a better choice because it produces fewer carcinogenic aldehydes upon heating (Chen et al., 2020). Cooking style also impacts the release of fumes. Deep-frying releases more fumes than stir-frying (Chen et al., 2020). One can use a fume extractor to reduce fume exposure. Chen et al. (2020) noticed nearly a 50% decline in cancer rates in patients upon using a fume extractor. It is important to note that factors like diet, environmental pollution, occupational exposure, and socioeconomic status can also impact outcomes. Nonetheless, next time you cook, keep these points in mind!
References
Chen, T.-Y., Fang, Y.-H., Chen, H.-L., Chang, C.-H., Huang, H., Chen, Y.-S., Liao, K.-M., Wu, H.-Y., Chang, G.-C., Tsai, Y.-H., Wang, C.-L., Chen, Y.-M., Huang, M.-S., Su, W.-C., Yang, P.-C., Chen, C.-J., Hsiao, C.-F., & Hsiung, C. A. (2020). Impact of cooking oil fume exposure and fume extractor use on lung cancer risk in non-smoking Han Chinese women. Scientific Reports, 10(1), 6774. https://doi.org/10.1038/s41598-020-63656-7
LoPiccolo, J., Gusev, A., Christiani, D. C., & Jänne, P. A. (2024). Lung cancer in patients who have never smoked — an emerging disease. Nature Reviews Clinical Oncology, 21(2), 121–146. https://doi.org/10.1038/s41571-023-00844-0
Robinson, K. M. (2022). Small-Cell and Non-Small-Cell Lung Cancer: What’s the Difference? WebMD. https://www.webmd.com/lung-cancer/small-cell-vs-non-small-cell-lung-cancer
Schabath, M. B., & Cote, M. L. (2019). Cancer Progress and Priorities: Lung Cancer. Cancer Epidemiology and Prevention Biomarkers, 28(10), 1563–1579. https://doi.org/10.1158/1055-9965.EPI-19-0221
About the Author
Arvan is a second-year student in the Honours Biochemistry program at McMaster University. He is an editor for the McMaster Health Technology blog. He also loves playing badminton and can’t live without coffee!
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