Reusing cooking oil is detrimental to health: New research shows increased risk of colon cancer and colitis

Your choice of food determines how healthy you will be. Bad diet and insufficient nutrition are the risk factors for several chronic diseases. Frying is a preferred style of cooking in most Indian households. Often the same oil is used to fry multiple times. This is precisely what the researchers are warning against. Once the cooking oil is heated, it undergoes thermal degradation leading to the formation of free radicals (uncharged oxygen molecules) which cause oxidative stress that in turn cause destruction at the cellular and molecular levels in the body. The damage caused by free radicals is devastating for the body.  According to a paper published on Aug 23 in the journal, “Cancer Prevention Research”, the researchers Jianan Zhang, Guodong  Zhang and Eric Decker have stated that there was exacerbated inflammation in the colon (a part of the large intestine), increased tumor size, increased gut leakage and surge in bacterial infection when they fed fried oil to mice. The researchers additionally caution people suffering from exacerbated colon inflammation and colon cancer to keep away from deep-fried foods. For the experiment, the researchers provided a combination of frying oil with fresh oil (unheated oil) mixed with the powdered diet to one group of mice. For another group, they provided a powdered diet mixed with only fresh oil. They tried to copy a normal human being’s diet with mice population. The result indicated that the mice group that was fed with a combination of frying oil mixed with fresh oil showed aggravated inflammatory symptoms of the intestines. Two Indian researchers Rekhadevi Perumalla Venkata and Rajagopal Subramanyam wrote a paper on ‘Evaluation of the deleterious health effects of consumption of repeatedly heated vegetable oil’ that was published in a peer-reviewed journal, ‘Toxicology Reports’. The paper says, 48% of people consume fried food 1-6 times a week and snacks account for 21% of all meals with the major type of snacks that are consumed constituting shallow and deep-fried foods. Repeated heating of oils at high temperatures (160–190°C) changes the viscosity, colour, foaming and decreases the smoke point (a temperature after which oil begins to generate toxic fumes and free radicals with gaseous vapours which is a marker of oil decomposition), thereby making it damaging for human health. These decomposed oils or fats is a risk factor for mutation and alteration in the gene which can initiate cancer spread. The number of free radicals is higher in oil heated three times than oil heated just once. So, the next time before eating those fried foods just pause and think about where and how it was cooked. Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health. To know more on this topic, please visit https://www.myupchar.com/en/tips/fat-sources-benefits-side-effects-in-hindi