Highly processed oils derived from soy, corn, canola, and other plants have long been promoted as very healthy, but they’ve recently been a cause of concern for many scientists. These vegetable oils are readily available in home kitchens and supermarkets these days, but they’ve only been in human diets for a short period of time.

The technology needed to process these oils wasn’t established until the early 1900s, resulting in a product that is still seen on grocery store shelves: Crisco. It was a frying fat made from cottonseed oil that looked like lard but was made by Procter & Gamble using a chemical technique and was first introduced in 1911.

Over the course of the 20th century, more refined vegetable oils emerged—they’re now commonly referred to as “seed oils” as a catchall phrase. Seed oils have become something of a nutritional gray zone in recent years.

While most mainstream nutritionists do not consider processed vegetable oils to be particularly unhealthy, several doctors and nutritionists believe that the specific fatty acids found in them cause inflammation and chronic health problems.

So, our question is: Is it necessary to abstain from all seed oils?

Although all cooking oils are made up of fatty acids, some dietitians and health professionals consider seed oils to be undesirable due to their greater quantities of polyunsaturated fats. A healthy person’s body fat has about 2% polyunsaturated fat. Nevertheless, the average person’s body fat contains up to 30% polyunsaturated fat, and apparently the cause is seed oils.

One of the main arguments against seed oils is that the fatty acids in them increase inflammation, which leads to chronic diseases that everyone wants to avoid. However, there is research that shows the contrary. Polyunsaturated fats, in particular, do not produce inflammation.

Keeping it simple

It’s difficult to know what to do with seed oils because there’s so much conflicting information out there. Many seed oils include a greater concentration of trans fats, which have been linked to heart disease. Changing to a different type of less-processed cooking oil is, of course, an option.

For sautéing vegetables or grilling fish or meat, olive oil, coconut oil, and avocado oil are all good choices. But there’s no need to become lost in the weeds of science.

The most essential thing to remember from this discussion on seed oils is that they’re widely present in many processed foods, including some blatantly unhealthy things like cookies, candy bars, and Twinkies, as well as other less obvious foods like pre-made hummus and salad dressing.

So, when it comes to your diet, start by eliminating processed foods, then develop a diet rich in a variety of whole foods and different types of fats.

If you’re looking to learn more about diets, we’ve broken two trending diets, the Galveston diet and the 5:2 diet.

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