It is often reported that Sri Lanka has a high incidence of lung cancer. Between 2,000 and 3,000 patients are diagnosed with the disease every year. Lung cancer has now become the second most common cancer among men. Smoking is widely known as the main cause of lung cancer in men. However, only a very small percentage of women in Sri Lanka smoke. Despite this, data from the National Cancer Control Programme since 2021 shows a clear increase in lung cancer among women as well.
So why has lung cancer increased among both men and women over the past 5–10 years? And how do women get lung cancer without smoking even a single day in their lives?
According to Dr. Waruna Gunathilake, Consultant Physician at the National Hospital of Colombo, recent research from China offers one important answer. The research, conducted with the involvement of the International Agency for Research on Cancer (IARC), points to cooking oil fumes (COFs) as a major risk factor—especially among non-smoking women in Asian countries.
The research shows that when vegetable oil is heated until it starts to smoke, it produces several harmful compounds. These include polycyclic aromatic hydrocarbons (PAHs), which are known carcinogens, and aldehydes, which are mutagenic substances. These compounds can damage cells and significantly increase the risk of lung cancer in people who are exposed to the fumes over long periods.
Dr. Gunathilake explains that in many Asian cultures, including Sri Lanka, food is often fried at very high temperatures, sometimes until the oil smokes. This is especially common in places with poor ventilation. Whether you are a man or a woman, long-term exposure to these fumes increases your risk of lung cancer.
He also points out that in Sri Lanka, many eateries from high-end restaurants to small street food stalls,use large quantities of vegetable oils for cooking. Exposure to cooking oil fumes may also increase the risk of other cancers, such as colon, breast, and prostate cancer.
Different oils produce different levels of harmful compounds, depending on how hot they are heated. One key factor that reduces risk is good ventilation. Cooking in an oven or in a well-ventilated space can reduce the risk of lung cancer by up to 50 percent.
Researchers have given several tips to reduce this risk, especially for women and professional chefs:
Tips to reduce this risk
Ensure that the kitchen or cooking area is well ventilated.
Use oils that can tolerate high temperatures, such as coconut oil, avocado oil, canola oil, or sunflower oil.
Use olive oil only for low-heat cooking or for salads.
Fry food only until it turns golden brown. Do not fry until the oil smokes.
Do not reuse oil that has already been used once. If frying again, coconut oil is the safest option.
Use healthier cooking methods such as boiling or steaming instead of frying whenever possible.
Use oils that can tolerate high temperatures, such as coconut oil
The situation in Sri Lanka may be even more dangerous. In many homes and restaurants, food is cooked without proper safety standards. Chinese-style cooking, which often involves very high heat and a lot of oil, is popular in Sri Lanka too. But how many of our chefs know about the risks? How many hours a day are they exposed to these fumes? There is no proper local research yet.
Most kitchens do not use proper fume extractors, and very few cooks wear protective masks. Food should never be cooked in small, enclosed spaces filled with smoke. If there is no fume extractor, there must be good natural ventilation.
If you look at the walls of many takeaway food stalls in Sri Lanka, they are often covered with thick oil stains. This shows how long food has been cooked in smoky oil. It also shows how much smoke workers and customers may be exposed to every day.
Clean the utensils properly
Another problem is poor cleaning of utensils used for deep frying. If oil layers are not removed properly, they burn again and again. This increases the release of toxic compounds and further raises the risk of lung cancer.
It is time for Sri Lanka to conduct its own scientific study, similar to the one done in China. These facts clearly show the need for urgent research and better awareness to protect both our chefs and our families from a silent but serious danger in our kitchens.
