The problem arises when the vegetable oil that is used for frying food is later reheated to fry other foods. The study, which appeared in Cancer Prevention Research, found that mice with breast cancer who consumed reheated cooking oil had a sharp rise in metastatic lung tumor formation.
The mice had been fed a low-fat diet for a week prior to being given the oils. Soybean oil was used in the study because it’s one of the most popular choices for frying food in the restaurant industry.
Twenty days after being injected with tumor cells, the mice who had eaten the reheated oil noted a metastatic tumor growth rate that was four times higher than those who ate fresh oil. They also had twice as many lung tumors, and their tumors were more invasive and aggressive than those who consumed fresh oil.
Reheating vegetable oil releases high amounts of acrolein, a toxin that has been linked to heart disease and neurological disorders. Unfortunately, many restaurants deep fry food using vegetable oils like soybean oil, which was used in the study, and they also tend to reuse it multiple times in order to save money and make their operations more efficient.
Meanwhile, a previous study published in the journal The Prostate revealed that the regular consumption of foods that have been deep fried raises a man’s risk of prostate cancer, particularly the more aggressive varieties of the illness.
In that study, researchers tied eating foods like French fries, donuts, fried fish and fried chicken more than once per week to a higher risk of the disease compared to those who ate such foods less than once per month.
In fact, eating these foods at least once a week raised the risk of prostate cancer anywhere from 30 to 37 percent in the study, even after controlling for factors like body mass index, age, a family history of prostate cancer, and race.
Frying food also adds a lot of calories to it. For example, a small baked potato weighing 100 grams has 93 calories and 0 grams of fat, which is not too bad on its own. However, that same amount of potatoes fried in the form of 100 grams of French fries has 319 calories and 17 grams of fat. Meanwhile, 100 grams of baked cod has 105 calories and a single gram of fat, but frying that same amount of fish will bring it up to 232 calories and 12 grams of fat.
Fried foods also tend to be rather high in trans fats, which have been associated with a higher risk of a laundry list of diseases, including cancer, obesity, diabetes and heart disease.
If this study is enough to make you shun fried food forever, that’s a good first step – but you might consider avoiding vegetable oils in all types of cooking, not just frying. Instead, try coconut oil, avocado oil, or olive oil, which can withstand high heat without deteriorating better than the unhealthy oils used in restaurants like canola, soybean, corn, sunflower, and cottonseed oil.
When it comes to preventing cancer, your diet can be incredibly powerful. It’s one of the biggest factors impacting your cancer risk that you can actually control, and giving up fried foods could be one of the best health decisions you ever make.
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