Is It Okay To Reuse Cooking Oil? Experts Explain Why You Shouldn’t!

In an attempt to save on expenses, most of us often reuse oil for cooking. It makes perfect sense, right? And oil seems so costly these days anyway so it must be okay.

Not actually, according to experts. In a Go Ask Alice! post, we learn that doing so exposes us to serious health risks.

Is it okay to reuse grease?

First off, Alice! is not a single person but a team of experts from Columbia University ranging from health professionals, research specialists, and writers. Their team members have “advanced degrees in public health, health education, medicine, counseling, and a number of other relevant fields” so yeah, they pretty much know what they’re talking about!

One reader wrote and asked:

“I am trying to convince my good friend not to save the grease she cooks with for re-use. Instead of draining grease out of a pan after frying it, she saves and stores it to use again. It seems to me that grease that is cooked once is bad enough, twice must be horrible. Am I unjustly picking on her, or am I right that there is an even greater health risk when you cook with pre-cooked oil/grease?”

Alice! responded:

“Although re-using cooking oil and/or grease is a somewhat common practice, it can pose some serious health hazards. The most common danger when recycling cooking oil is that it becomes rancid or spoiled. In addition to having strange flavors and odors, rancid oil may contain possibly carcinogenic free radicals. These pesky molecules are then absorbed into the fried food and ingested by an unlucky eater.”

“Using fresh oil every time you cook is the healthiest option,” according to Alice!

It is possible to reuse, provided you keep certain things in mind.

According to the website, there are “helpful (and healthful)” ways to reusing grease if fresh oil isn’t always available.

Alice! shared 7 tips:

1. 1. Strain it through a few layers of cheesecloth to catch any food particles before storing. Be careful with hot oil, though, because you can easily get burned.
2. 2. Shake off excess batter from food before frying it.
3. 3. Use a good thermometer to fry foods at a maximum of 375°F (or 190°C).
4. 4. Turn off the heat after you are done cooking. Exposing oil to prolonged heat accelerates rancidity.
5. 5. Don’t mix different types of oil.
6. 6. Store oil in a cool, dark place.
7. 7. Avoid iron or copper pots or pans for frying oil that is to be reused. These metals also accelerate rancidity.

Oil safety is very important.

Alice! concluded:

“Here’s another tip on oil safety. Frying foods at or above 375°F can lead to the accumulation of 4-hydroxy-2-trans-nonenal (HNE) in the oil. What’s that, you ask? HNE is a toxic substance that has been associated with an increased risk of stroke, atherosclerosis, elevated levels of LDL cholesterol (the “bad” cholesterol), Alzheimer’s, Parkinson’s, and various liver diseases. It only takes one use to create HNE in the oil, and reusing oil at too high of a heat can cause even more HNE to build-up.

“How to avoid HNE? When heating oil to very high temperatures, use a thermometer to ensure that you’re not heating the oil above 375°F. This is the ideal temperature for frying. Also, stick to oil low in linoleic acid, such as olive oil and canola oil. Researchers found that HNE is more likely to build up in oils with high levels of linoleic acid. Oils with the highest percentage of linoleic acid are safflower oil, grape seed oil, sunflower oil, and corn oil, so you may want to stay away from those if you enjoy a deep fryer.”

So the next time you’re tempted to reuse cooking oil, you might want to think twice.