There are many cancer risks which might be hidden from our bare eyes. For instance, constant exposure to harmful sun rays, pollution, smoking, chronic health problems and foods like processed and red meats. Cooking oil is also one of them.
Undoubtedly, vegetable or cooking oils are the major part of our Indian lives. These oils are the base of Indian cuisines. It is used for frying, stir fry, saute, baking, dressing, extrusion and marinating purposes.
Some people's love for fried food is also omnipresent. Deep frying of vegetables and many other foods is one of the most common practices for preparing the foods.
However, repeatedly heating cooking oil at high temperature is not good. Deep frying needs oil in large quantities, but all oil can't be used at one time. This is the reason, people use that cooked oil again and again for cooking, which is not good for health at all. It is associated with an increased risk of getting high blood pressure, elevated cholesterol levels, atherosclerosis and other cardiovascular problems.
It is also one of the major risk factors for cancer development. Many cancer researchers found that reheated oils produce mutagenic, carcinogenic and genotoxic effects.
Do you know why this repeat use of vegetable oil is so harmful? Let's take a look:
When we heat the oil at temperature 170 to 220ºC, it goes through many reactions like hydrolysis and oxidation. This degrades the oil into many components. The repeated heating of such oil can generate free radicals, lipid radicals, and increase the acid value of oil.
Let's understand this with a diagram (Adapted from Critical Reviews In Food Science And Nutrition) -
Repeatedly heated oil produces polycyclic aromatic hydrocarbons. These molecules are highly lipid-soluble. These are known mutagenic and genotoxic molecules, which cause mutations in healthy cells.
They react with DNA, cause mutation alters lipid and protein structures. This disturbs the omega 3 and omega 6 healthy ration in the body and increases the amount of frying food by-products. All together known to create a suitable environment for cancer cells to grow and progress.
This is the reason, the consumption of fried food is associated with many malignancies like breast, colon, kidney, rectum, and pancreas.
Association of repeatedly heating cooking oil and cancer risk
It has been evaluated from an analysis that the intake of fried food in large proportions is associated with 1.3 to 2.3-fold rise in the risk of prostate cancer.
One more analysis has also shown a relation between rancified cooking oil and prostate cancer. It showed that deep fried carbohydrate-rich foods like potatoes are associated with higher risk of prostate cancer as these produce acrylamide, a carcinogen.
It has been reported that harmful fumes (containing mutagenic compounds) and other hazardous components produced by repeatedly heating vegetable oil known to cause breast cancer.
It is evaluated that the most of the oils used for cooking in homes contains trans fatty acids, which can be a major risk factor for breast cancer.
It is found that females who are exposed to fumes emitted from reheated cooking oil are at high risk of lung cancer.
The heterocyclic amines (HCAs) generated during the deep frying of foods containing proteins like eggs, meat or fish are known as potent mutagens and carcinogens.
This can be evident how dangerous the reheated cooking oil is for overall health. It can be a potent risk factor for various types of cancers. So, avoid using already used oil again and again and at high temperature as it can lead your health towards the path of diseases and infections. Throw it or keep it to lighten emergency lamps, biofuels or as ant poison.
What type of cooking oil should I prefer?
Along with knowing what not to use, you should also be aware of what type of oils should use for cooking. Saturated and trans fats are not good for health. This will contribute to reducing your risk of developing many health problems like high blood pressure, cholesterol, and heart attack. This also helps in lowering the risk of developing cancer.
Most of the cooking oils are known to contain saturated fat. Oils that contain low levels of saturated fats contain high unsaturated fats.
If you are looking for a healthy option then go for low saturated and trans fat oils. Tropical oils, for example, coconut oil and palm oil are rich in saturated fat, therefore avoid using these. Use oils rich in monounsaturated fats and polyunsaturated fats. Olive, canola, and sunflower oils are best to add.
How to use every type of oil?
One more reason to get problems from cooking oils is their wrong use. Every oil has specific smoke points. This decides whether the oil should be used for frying or as dressing. Let’s explore the types of oils as per their smoke points -
- For Frying - Use oils having a high smoke point. For instance, avocado oil, refined olive oil, canola oil, safflower oil and peanut oil.
- For Sauteing and Searing - Choose oil with a low smoking point like extra virgin oil and sesame oil.
- For Baking - Use oils with neutral tastes like canola or olive oil.
- For Dressing - The best oil for dressing is virgin oil. However, you can use any oil of your choice.
These are the points you all should take in mind while using cooking oils. This will significantly help you to use these in a healthier and safer way. Adopt these things in your daily cooking and see a change in your health.
You might also be interested in knowing other healthy lifestyle habits to adopt to keep cancer at bay. Read here to know these ‘5 mandatory lifestyle modifications for cancer patients to be adopted after-treatment’.