It is common knowledge that fried foods are not good for us.  The first reason is most fried foods are cooked in unhealthy oils that create a significant inflammatory response within our bodies that causes disease.  The oils typically used are soybean, sunflower, corn, canola, etc. Even worse, these oils can be hydrogenated (trans fats) which can cause greater inflammation and high cholesterol.

Another reason fried foods are bad is because when these oils are heated and reheated over and over again, high levels of toxins called aldehydes are released in the oil and into the food.  Researchers from Spain found when certain cooking oils are heated, the fatty acids degrade significantly. This degradation results in the production of toxic aldehydes and upon consumption, these toxins react with human proteins, enzymes, and hormones, which can lead to serious health problems. Aldehydes are chemicals known to cause neurological disease and cancer. 

The researchers tested sunflower, flaxseed and olive oils by heating them at temperatures of 374 degrees Fahrenheit.  They discovered that sunflower oil was the worst offender for toxic aldehydes, followed by flaxseed oil, also known as linseed oil, and olive oil. They also found the more times these oils were reheated, the worse their concentrations of toxic aldehydes became.

Another recent study has found that regular consumption of deep fried foods increases the risk of prostate cancer by one-third.

What We Have To Say:  Completely avoid fried foods (including french fries) when eating out!  Sautéing your food in a skillet or making “oven fries” at home is healthier.  Use olive oil or coconut oil and keep temperatures at 350 degrees or below.

Sources:

https://www.eurekalert.org/pub_releases/2012-02/f-sf-tad022212.php

https://www.deepdyve.com

https://cameochemicals.noaa.gov/chemical/2330

https://www.sciencedaily.com/releases/2013/01/130128142849.htm