There are many foods that are labeled “unhealthy”, and these depend largely on the nutrition paradigm you follow.

However, there is one food that is universally not good for you and should be avoided as much as possible. And that food is vegetable oil.

Avoiding vegetable oil can be challenging, as vegetable oil is in many prepackaged and processed foods, as well as takeout and restaurant meals. It is everywhere.

However, as you’ll soon see, it’s so important to avoid it, as it’s probably affecting your health more than you realize.


There are several reasons why vegetable oils are so bad for us:

Vegetable oils are rich in omega-6 fatty acids. While these acids, like omega-3 fatty acids, are important to our health and must be obtained through diet, we are consuming too much of them. These omega-6s upset the omega 6:omega 3 balance and cause inflammation.

Vegetable oils are a relatively new addition to our diet: oils like butter, lard, and coconut oil have been around for much longer, creating what’s known as “evolutionary incompatibility.”

These oils are incredibly unstable, meaning they can easily oxidize and produce harmful by-products.
This oxidation leads to the production of free radicals, which are molecules that can damage our cells, as well as cause inflammation and disease. This is dangerous for the brain, as the brain is especially vulnerable to free radicals.

Chris Kresser highlights the terrifying production process of vegetable oils:

“First, seeds are gathered from the soy, corn, cotton, safflower, and rapeseed plants. Next, the seeds are heated to extremely high temperatures; this causes the unsaturated fatty acids in the seeds to oxidize, creating byproducts that are harmful to human and animal health. The seeds are then processed with a petroleum-based solvent, such as hexane, to maximize the amount of oil extracted from them. Next, industrial seed oil manufacturers use chemicals to deodorize the oils, which have a very off-putting smell once extracted. The deodorization process produces trans fats, which are well known to be quite harmful to human health. Finally, more chemicals are added to improve the color of the industrial seed oils.”

As you can see from this process, these oils have numerous chemical additives and contain various toxic by-products created by this process.

Consuming these oils leads to chronic inflammation and has been linked to nearly every health condition, from asthma and diabetes to autoimmune diseases and depression.

Action Steps

Oils to avoid:

  • Canola
  • Corn
  • Cottonseed
  • Soybean
  • Sunflower
  • Safflower
  • Peanut oils

Cook with these oils:

  • Olive oil
  • Butter
  • Coconut oil
  • Lard