The diet has a significant impact on liver health, and the way cooking oil is used plays an important role.
Cooking oil is refined from plant or animal sources, exists in liquid form, and has a greasy texture when in contact with skin membranes in normal environments. The use of cooking oil in food preparation is increasingly popular, becoming an essential item in most kitchens. For the liver, the choice and use of cooking oil are also very important.
The Role of Cooking Oil in Liver Health
Considering the importance of cooking oil for the liver, it is an essential nutrient in our daily diet, especially for absorbing and utilizing fat-soluble vitamins. Notably, studies by the WHO indicate that selecting the right cooking oil can alleviate the burden on the liver, helping to protect liver health.
Firstly, cooking oil contains a certain proportion of essential fatty acids, such as linoleic acid and linolenic acid, which are necessary for cells to synthesize and secrete bile and lipids. Secondly, cooking oil contains beneficial compounds for the human body such as unsaturated fatty acids, sterols, carotenoids, and antioxidants, which can reduce the risk of atherosclerosis.
Moreover, choosing and using cooking oil properly can also reduce the burden on the liver. For instance, selecting oils that are low in fat, low in cholesterol, and easy to digest and absorb can decrease the overall oil consumption, thus avoiding liver function damage caused by excessive intake over long periods. People should also pay attention to an appropriate amount of cooking oil in their diet, avoiding excessive consumption that increases the burden on the digestive system to protect liver health.
Because the way cooking oil is used has such a large impact on liver health, the WHO recommends avoiding or steering clear of the following three types of cooking oil to prevent liver damage:
1. Reused Cooking Oil
Repeatedly using cooking oil is far more harmful to health than we often think. It is not only a misguided way to save money but also a habit that brings diseases to the body, especially to the liver.
When cooking oil is reused multiple times, it can release harmful chemicals such as acrolein, acrylamide, and tetrahydropyran. These are considered significant contributors to liver cell damage.
Repeatedly reused cooking oil is very harmful to the liver, potentially leading to liver cancer. (Illustrative image).
Additionally, fried foods contain high levels of fat and sugar, and consuming too many fried foods over time can lead to chronic diseases such as obesity and metabolic syndrome, subsequently causing liver damage. It can also harm blood vessels and increase the risk of cardiovascular diseases. Therefore, you should blacklist repeatedly reused oils to protect your health.
2. Homemade or Small-Scale Pressed Oils
Although homemade oils from small presses are very cheap, they pose certain health risks. This is similar to making cooking oil at home.
This is due to the risk of using moldy ingredients for extraction; the oil extracted is easily contaminated with mold, leading to reduced oil quality. Additionally, if fermentation tanks, oil storage tanks, and other equipment are not cleaned and sanitized promptly during extraction, the oils can easily become contaminated.
Meanwhile, homemade oils or those pressed at small workshops are prone to hygiene issues, insufficient sterilization, and lack of quality assessment according to standard regulations. They also have shorter shelf lives or may not be clearly labeled, making it easy to consume them after their expiration dates.
Commercially processed oils often have benzopyrene levels that do not meet standards due to poor quality raw materials or contamination during processing. Long-term use can increase the risk of cancers such as stomach cancer and esophageal cancer.
Moreover, because oils from small workshops are improperly sealed, during transportation, exposure to air, light, and microorganisms can cause peroxide values to exceed standards. If used during this time, it can lead to various diseases such as stomach cancer, liver cancer, and cardiovascular diseases.
Therefore, it is best not to press your own oil or purchase oil from small, untrustworthy sources to avoid a large amount of harmful substances entering your body, which can stimulate liver cell damage and increase cancer risk.
3. Expired Cooking Oil
Continuing to use cooking oil even when it has passed its expiration date is a not uncommon habit. Some people even believe this is a virtue, demonstrating thriftiness and avoiding waste. Others may be too busy or indifferent to pay attention to the expiration date of cooking oil when cooking.
Cooking oils left for too long often have a hazelnut smell, which is a sign of rancidity. This is because cooking oil contains linoleic acid, which can oxidize to form aldehydes or ketones. Excessive absorption can increase the burden on digestive organs, particularly the liver. Additionally, when cooking with rancid oil, it can produce smoke containing epoxy propionaldehyde, which can cause poisoning if inhaled in large amounts.
In addition to opened oils that have gone rancid, expired cooking oil can also harm health as they will produce lipid peroxides. This substance not only poses a cancer risk but can also damage blood vessels.
Therefore, we should pay attention to the storage and use of oil within the appropriate time frame, avoiding the use of expired and substandard oils.
