Most ingredient lists for your favorite packaged items contain at least one vegetable oil. Vegetable oils are everywhere, from chips to popcorn to granola bars, and overall consumption has increased considerably over the past 100 years. Moreover, global vegetable oil production has expanded by over 1600% since the early 1900s, has doubled in the previous 20 years, and is predicted to increase by 30% in the next four years. Since 1909, the consumption of soybean oil alone has increased 1,000-fold in the United States. Chronic disorders such as obesity, heart disease, cancer, and diabetes are all rising as vegetable oil use rises. In this post, we’ll explain what seed oils are, how they’re made, what they do in your body, and why avoiding them is essential for cellular health.
What is Seed Oil?
Seed oils, also known as industrial seed oils, are a kind or subset of vegetable oils generated from seeds that are often higher in linoleic acid and, therefore, may be harmful to your health. These oils, which are almost always derived from crop seeds, include:
- Rice bran
What Is the Difference Between Saturated and Unsaturated Fat?
Before we go into how seed oils influence your health, we must understand the distinction between saturated and unsaturated fats. Saturated fats are more stable and less flexible structurally than unsaturated fats. This is because they are “saturated” with hydrogen atoms, which causes them to be solid at room temperature, able to endure higher heat, and hence more “stable.” Unsaturated fats, on the other hand, have one or more double bonds. Double bonds are parts of the fatty acid chain that lack hydrogens, giving them greater flexibility and more prone to oxidation or rancidity. When there are many double bonds, the unsaturated fat is called polyunsaturated after the first bond on the chain.
It’s an omega-3 fatty acid, for example, if the initial double bond is on the third link of the chain. It’s an omega-6 fatty acid if the initial double bond is on the sixth link in the chain. The more double bonds there are, the more susceptible the fat is to oxidation caused by air, light, and heat exposure. Seed oils are notably abundant in linoleic acid, an omega-6 fatty acid that humans did not consume in large quantities until the last century. To function, your body requires both saturated and unsaturated fats. Yet, newer fat sources, such as seed oils, can disrupt the body’s natural fat balance and lead to unprecedented levels of health issues, ranging from increasing obesity levels to heart disease and more.
How Are Seed Oils Made?
Most foods, from bacon and butter to pure pea protein, are processed before they reach the grocery store. Food processing isn’t necessarily harmful or hazardous in and of itself. Still, the processing and the inclusion of certain chemicals and preservatives can pose substantial health risks over time. Manufacturers use high temperatures and harsh chemicals to extract seed oils from the seed to the bottle, which often results in harmful byproducts like trans fats. In many situations, synthetic antioxidants are added to extend the shelf life of the unstable fats in seed oils. Synthetic antioxidants such as TBHQ, BHA, and BHT have known carcinogens. The following is a step-by-step process for producing most seed oils:
- Plants such as corn, soybean, safflower, sunflower, rapeseed, and others provide seeds. Regrettably, more land is allocated to vegetable oil crops than to all vegetables, fruits, legumes, nuts, roots, and tubers combined, resulting in record deforestation rates – a major contributor to climate change.
- The seeds are heated to extremely high temperatures, resulting in oxidative damage and the transformation of certain PUFAs to harmful trans fats.
- The seeds are then extracted with a chemical solvent, such as hexane, for a higher yield.
- The seed oils are then deodorized at high temperatures, which may further degrade the unstable PUFAs and increase trans fat formation.
- Lastly, chemical preservatives such as the carcinogenic compounds BHT and BHA are occasionally added to extend the shelf life of the oils.
Top Dangers of Seed Oils
As the global use of seed oils has grown, so has the incidence of chronic illnesses such as cardiovascular disease, diabetes, autoimmune disease, macular degeneration, and neurological disease. What’s the connection here? The dangers of seed oils are classified into various categories:
- Unusual amounts of omega-6 fats
- Disrupts the composition of cell membranes
- It increases oxidative stress and inflammation.
- Trans fats
- Harmful chemical additives
- Obesity, heart disease, diabetes, autoimmune illness, Alzheimer’s disease, and other conditions have been linked to it.
Top Seed Oils to Stay Away From
You should try to reduce your seed oil consumption as much as possible. Yet, our food supply is already riddled with these oils, and eliminating them may be difficult. Especially when practically every restaurant, from fast food to five-star, uses them in almost every dish.
With that in mind, here is a list of the worst high-linoleic seed oil offenders.
- Grapeseed oil (between 66.0% and 75.3%)
- Safflower oil (70% linoleic acid)
- Sunflower oil (66% linoleic acid)
- Soybean oil (55% linoleic acid)
- Cottonseed oil (53% linoleic acid)
- Corn oil (60% linoleic acid)
- Rice bran oil (30% linoleic acid)
- Peanut oil (25-29% linoleic acid)
- Canola oil (17-21% linoleic acid)
What to Use Instead
Vegetable oils with lower linoleic acid content and higher smoke points include avocado, coconut, and olive oil. Each of these, however, comes with trade-offs.
Extra virgin avocado oil has a high smoke point ranging from 428 to 482°F, making it an excellent choice for high-heat cooking. In addition, it has more monounsaturated fats and vitamin E than many other industrial seed oils.
Coconut oil is low in polyunsaturated fats (PUFAs), with about 2% linoleic acid, and it is rather heat stable, having a smoke point of around 375°F. Unfortunately, its rich coconut flavor might cause your food to taste the same after a while. Moreover, coconut oil production, like many other oil crops, has a large environmental impact and is connected to the loss of tropical biodiversity.
Olive oil is well-known for its high monounsaturated fat content and low smoke point. It is also more resistant to oxidation during frying than other vegetable oils.
When it comes to something as prevalent as seed oils, it’s easy to overlook the dangers and believe they must be safe because they’re in so many foods and used so freely. Sadly, this is not always the case, especially regarding linoleic acid-rich oils. If avoiding all seed oils at once seems overwhelming, start by observing what fats you consume regularly. Examine your favorite packaged foods, and don’t be afraid to ask restaurants what oils they use in their dressings, sauces, and deep fryers. It’s not about perfection, but your cells will appreciate you for every step you take away from overly processed seed oils. We hope this post answered all your questions regarding what seed oils are and whether or not you should avoid them.