What Are Seed Oils And Should You Avoid Them? | Zero Acre Farms

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What Are Seed Oils And Should You Avoid Them?

May 8, 2022
WRITTEN BY: Emily Ziedman, MS

Article at a Glance

Introduction

If you look at most ingredient lists on your favorite packaged foods, you'll likely see at least one type of vegetable oil. From chips to popcorn to granola bars, vegetable oils are everywhere, and overall consumption has increased dramatically over the last 100 years.

In fact, global production of vegetable oils has increased over 1600% since the early 1900s, has doubled in the last 20 years, and is expected to grow 30% in the next four years. In the U.S., the consumption of soybean oil alone has grown 1,000-fold since 1909.

And with this increase in vegetable oil consumption, chronic diseases like obesity, heart disease, cancer, and diabetes are also on the rise.

Today, at least 60% of American adults suffer from chronic illness — a 700% increase since the first survey on the topic in 1935. Before modern diets and lifestyles, chronic diseases were rare. Could the rise in industrial seed oil consumption have anything to do with it?

In this article, we’ll define what seed oils are, how they’re made, what they do in your body, and why avoiding them is crucial for cellular health.

What is Seed Oil?

Seed oils, often called industrial seed oils, are a type or subset of vegetable oils that are derived from seeds and are typically higher in linoleic acid, and therefore, may be worse for your health.

These oils are almost always derived from the seeds of crops and include:

Vegetable oils, on the other hand, are all oils or fats derived from plant matter, whether it’s from fruits, grains, seeds, or nuts. In other words, vegetable oils are a broad category that includes all plant-based oils. Some of the most popular “vegetable” oils include:

A Quick History of Seed Oils

While fat has always been a part of the human diet, seed oils were only introduced to the food supply in significant quantities about 100 years ago. First, in the form of shortening (Crisco), and soon after as the myriad of cooking oils we know today, from soybean oil, corn oil, and canola oil, to safflower oil, sunflower oil, and more.

Not surprisingly, it took the American public a few decades to trade in traditional fats for seed oils, but over time (with the help of plenty of creative, health-oriented, and sometimes patriotic marketing campaigns), these new oils won their way into the hearts and homes of people across the United States.

What catapulted the popularity of seed oils, however, was a new surge of research published in the 1950s that unveiled the connection between saturated fat and heart disease. Traditional forms of dietary fat like butter and lard are rich in saturated fat, while seed oils are primarily made up of polyunsaturated fats.

What’s the Difference Between Saturated And Unsaturated Fat?

Structurally, saturated fats are stable and less flexible than unsaturated fats. This is because they are "saturated" with hydrogen atoms, making them solid at room temperature, able to withstand higher heat, and therefore, more "stable."

On the other hand, unsaturated fats have one or more double bonds. Double bonds refer to an area on the fatty acid chain where hydrogens are missing, creating more flexibility and making them more susceptible to oxidation or rancidity.

When there is more than one double bond, the unsaturated fat is called polyunsaturated, named after the first bond on the chain. For example, if the first double bond is on the third link of the chain, it's an omega-3 fatty acid.

If the first double bond is on the sixth link on the chain, it's an omega-6 fatty acid. The more double bonds, the more susceptible the fat is to oxidation via exposure to air, light, and heat.

Seed oils are particularly rich in the omega-6 fatty acid known as linoleic acid, a fat that humans didn’t eat in high quantities until the last 100 years or so.

How Seed Oils Are Made

Most food you eat, from bacon and butter to pure pea protein, are processed before they hit store shelves. The processing of food isn’t inherently bad or dangerous, but the type of processing and the addition of certain chemicals and preservatives can pose serious threats to your health over time.

In order for seed oils to get from the seed to the bottle, manufacturers use high temperatures and harsh chemicals, often resulting in harmful byproducts like trans fats.

Here is the step-by-step process of making most seed oils:

  1. Seeds are gathered from plants such as corn, soybean, safflower, sunflower, rapeseed, and so on.
  2. The seeds are heated to extremely high temperatures, causing oxidative damage and transforming some PUFAs into damaging trans fats.
  3. The seeds are extracted with a chemical solvent, such as hexane.
  4. High-heat deodorization occurs, which may further damage the unstable PUFAs.
  5. Chemical preservatives are sometimes added to enhance shelf life, including BHT and BHA.

6 Top Dangers Of Seed Oils

As the consumption of seed oils has steadily increased throughout the world, so has the incidence of several chronic diseases, including cardiovascular disease, diabetes, autoimmune disease, macular degeneration, and neurological disease.

Too Many Omega-6 Fatty Acids

Your body requires a variety of different types of fats to function. Polyunsaturated, monounsaturated, and saturated fats all play a vital role. But too much of one kind of fat can throw off fatty acid balance and result in health issues.

Omega-6 and The Cell Membrane

Every single cell in your body is made up of a protective membrane called the lipid bilayer.

With that being said, the dynamic nature of the membrane is reliant on its composition. Cell membranes need saturated fats for stability and structure, while unsaturated fats allow for fluidity and flexibility.

Inflammation

While you need dietary omega-6 fatty acids in extremely small amounts, soaring levels of linoleic acid consumption can trigger a cascade of inflammation in the body.

Oxidative Stress

High levels of omega-6 fatty acids can also trigger oxidative stress, leading to cellular damage.

Trans Fats

Another danger of seed oils is the presence of trans fatty acids. Even moderate levels of trans fats can wreak havoc on cell membranes.

Harmful Chemical Additives

During the processing of seed oils, harmful chemicals are added to enhance yield and promote the longevity of the product's shelf life.

Health Issues Associated With Seed Oils

Autoimmune Disease

Research suggests that vegetable (seed) oils may contribute to autoimmunity by impacting antioxidant systems and inflammatory pathways.

Heart Disease

Research shows that seed oils rich in linoleic acid can promote several factors that set the stage for cardiovascular disease.

Alzheimer's Disease

Evidence suggests that fatty acid levels are linked to cognitive health, with higher levels of omega-6 fats leading to reductions in cognition.

Obesity

Seed oils are a significant cause of unwanted fat gain that you can easily remove from your diet.

Diabetes

Research suggests that omega-6 fats increase insulin secretion while also reducing its breakdown, leading to impaired insulin action.

Macular Degeneration

AMD is the leading cause of blindness globally and one of the only conditions where it's widely recognized that excess omega-6 fatty acids are the culprit.

Top Seed Oils to Avoid

With that in mind, here is a list of the worst offenders when it comes to high-linoleic seed oils:

What to Use Instead

Vegetable oils like avocado, coconut, and olive oil are known for their slightly lower linoleic acid content and decent smoke points.

Avocado Oil

Extra virgin avocado oil boasts a high smoke point between 428-482°F.

Coconut Oil

Coconut oil is low in polyunsaturated fats (PUFAs), containing only 2% linoleic acid.

Olive Oil

Olive oil is known for its high monounsaturated fat content and relatively high smoke point.

Zero Acre oil

Zero Acre oil is a cooking oil without many compromises. High in heart-healthy and heat-stable monounsaturated fat, Zero Acre oil has a sky-high smoke point of 485°F and a clean neutral taste.

The Takeaway

With something as pervasive as seed oils, it can be easy to overlook the harm and assume they must be safe if they're included in so many foods and used so freely.

Unfortunately, that's not always the case — certainly not when it comes to oils rich in linoleic acid.

If it feels overwhelming to try to avoid all seed oils at once, begin by just noticing what types of fats you consume on a daily basis. Check your favorite packaged snacks, and don’t be shy about asking restaurants what kinds of oils they use in dressings, sauces, and deep fryers.