When you follow a keto or low carb diet, you get all of the sugar and refined carbs out of your diet. But, if you replace those foods with seed oils, you may be doing more harm than good. This blog post explains why you should be just as concerned, if not more so, about getting rid of seed oils as you are about sugar.
The Problem with Seed Oils – At-A-Glance
- Examples of seed or vegetable oils: soybean oil, canola oil, corn oil, cottonseed oil, peanut oil, sunflower oil, and safflower oil.
- Many of these refined seed oils are high in inflammatory omega-6 fatty acids.
- Seed oils are often hard to extract and must be pulled out using harmful chemicals or heat that causes them to degrade.
- Seed oils can be manipulated to give us trans fats.
This Food is Worse than Sugar on a Keto (Low Carb) Diet [Video]
In this video, you’ll learn…
- Examples of seed oils.
- Health problems these oils cause.
- Ways to protect yourself from them.
It’s Not Just Saturated vs. Unsaturated
For many years, we thought we had cracked the code on which fats are good for us and which are bad, and the code was simple. Saturated fats are bad and unsaturated fats are good, especially polyunsaturated seed oils or vegetable oils as they are often called.
Eating was made simple. Stop eating saturated fats and switch to seed or vegetable oils extracted from plants like soybeans, canola, corn, cotton seeds, peanuts, and sunflower or safflower seeds.
We went along with this simplified approach for many years, but then some problems started to arise that blurred the line between what we had thought to be good and bad fats. For one example, coconut oil is mainly composed of saturated fatty acids.
However, it is high in a special type of fatty acid known as lauric acid. Lauric acid has been shown to significantly increase high-density lipoproteins or HDLs. We think of HDLs as the good cholesterol (1).
Despite the fact that we’ve been trained to think that eating saturated fat increases your risk of cardiovascular disease, here we have a saturated fat that has a protective effect.
We also started to see a growing body of research, furthering this idea that saturated fats are not the direct path to heart disease that they were once thought to be (2).
Saturated fats don’t get a complete pass when it comes to health. Saturated fats may raise LDL cholesterol, and how your body handles a diet high in saturated fats may be determined by your genes. However, when the goal is to reduce saturated fat, the answer that was offered was to increase unsaturated seed oils.
This concept took hold and grew rapidly. In fact, if you go to your pantry right now, you will likely find many foods with soybean oil or other seed oils listed prominently on the ingredient list. Even foods that are promoted as healthy, like salad dressing, peanut butter, and packaged diet foods, contain them making it hard to avoid these unhealthy oils.
What’s the Problem with Seed Oils?
What is so bad about seed oils? There are three main issues. First, many of these refined oils are high in inflammatory omega-6 fatty acids. Second, these oils are hard to extract and must be pulled out using harmful chemicals or heat that causes them to degrade. Third, these oils can be manipulated to give us trans fats. Let’s look at each of these issues.
Chronic inflammation is the root cause of many diseases and starts to show itself in a variety of ways. If aches, pains, fatigue, depression, anxiety, and unexplained weight gain bother you, inflammation may play a role. Seed oils create inflammation because they are high in omega-6 fatty acids.
Before seed oils became so prevalent in our world, the typical human diet provided omega-6 and omega-3 fatty acids in a balanced ratio of about 1:1. Today, it is estimated that the ratio is closer to 20:1 (3).
It is this rise in omega-6 relative to omega-3 that is thought to create inflammation and may play a role in the growing obesity epidemic that we face.
Prone to Degrade
I also mentioned that these oils are hard to extract and must be pulled out using harmful chemical solvents or heat that cause them to degrade. What does it mean to degrade, and why is that bad?
Seed oils are high in polyunsaturated fatty acids (PUFAs), which means their chemical structure contains multiple double bonds between carbon atoms.
Having a double bond in its chemical structure is kind of like having the two carbons shaking both hands with each other, which is awkward. So, these molecules are less stable and are looking for a free atom to grab onto, like an oxygen atom.
This lack of stability is enhanced when the fatty molecules are exposed to elements like light and heat. If this oxidation happens, it changes or degrades the oil in ways we don’t want. For instance, oxidation can cause the oil to release oxidation products like free radicals that damage cells.
Here we have unstable seed oils that have already been exposed to heat during the extraction phase that we are pouring into super hot deep fryers to cook french fries and chicken nuggets. So the cell-damaging oxidative products are multiplied.
Even more challenging, this cell damage does not show itself right away. You can consume fried foods and eat out of a box for years before you find yourself dealing with heart disease, cognitive decline, inflammatory bowel disease, and other chronic disorders associated with these inflammatory omega-6-rich foods (4).
Curious about cooking with saturated fats, olive oil, and avocado oil? See my blog post on the best cooking oils for a low-carb and keto lifestyle.
Another problem with vegetable and seed oils is that their available bonds allow them to bind to hydrogen through a process known as hydrogenation. Food manufacturers like to hydrogenate seed oils because it turns the liquid oil into a solid fat. This greatly increases the shelf-life of the food.
However, your body does not like this because this is where trans fats come from, which are well-known for their health risks. These hydrogenated oils are found in things like Crisco and Margarine, which puts those ingredients and the foods made with them in the not-good column.
When you follow a low carb/high fat diet, like keto, it’s easy to see that sugar doesn’t have a place in your diet. However, seed oils are pure fat, so excluding them is not as intuitive. These oils are cheap, so they are the oils restaurants and packaged food companies typically use. Despite being in so many convenience foods, there are ways to protect yourself from them.
First of all, cook at home. It is a great skill to learn. You know what’s in your food, and it saves you money.
Next, eat whole foods. If it comes in a box, look at the ingredient list for the presence of a seed oil or keywords like “hydrogenated” or “partially hydrogenated oil.” As a bonus, when you eat whole foods, you take in cell-defending antioxidants. These antioxidants counteract the oxidative stress that junk foods can create.
Thank you for reading and have a wonderful week!
(1) Chinwong, Surarong, Dujrudee Chinwong, and Ampica Mangklabruks. “Daily consumption of virgin coconut oil increases high-density lipoprotein cholesterol levels in healthy volunteers: a randomized crossover trial.” Evidence-Based Complementary and Alternative Medicine 2017 (2017).
(2) De Souza, Russell J., et al. “Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies.” Bmj 351 (2015).
(3) Simopoulos, Artemis P. “An increase in the omega-6/omega-3 fatty acid ratio increases the risk for obesity.” Nutrients 8.3 (2016): 128.
(4) Patterson, Elaine, et al. “Health implications of high dietary omega-6 polyunsaturated fatty acids.” Journal of nutrition and metabolism 2012 (2012).