Vegetable oil is one of those ingredients you can find in most home kitchens. It seems harmless—after all, it has the word “vegetable” on the label, and vegetables are healthy, right?
But there are some hidden dangers lurking in those vegetable oil bottles that I’d like to bring to light. While I could use a lot of “science speak” to explain the potential harms, I’ll instead just gloss the basics and get right to the information that matters most to you.
Whole, unprocessed foods (like bananas) contain more nutrients than foods that have been processed (like chips). Vegetable oil falls into the processed category. Pretty much all vitamins and nutrients are removed from it, which means it’s full of “empty” calories. It’s also full of trans fats (unsaturated fats that have been chemically modified to be solid at room temperature), which are hugely unhealthy.
Additionally, vegetable oil contains an excessive amount of Omega-6 fatty acids. Omega-3 and Omega-6 have been termed “essential” fatty acids because our bodies can’t produce them. So, in moderation, we need to consume them because they play a role in our bodies’ inflammation, immunity and blood-clotting processes. The catch is that we need to get Omega-3 and Omega-6 in a certain balance. When we have more of one than the other, we get all out of whack. Unfortunately, many people’s diets heavily favor Omega-6, and vegetable oils are the biggest source of it in the diet by far.
One particular Omega-6 fatty acid – linoleic acid – tends to cause the most problems when consumed in excess. It also happens to be the main fatty acid in several vegetable oils. Linoleic acid accumulates in our fat cells and cell membranes, leading to actual structural changes within our bodies’ tissues.
So what does all of this mean for our health? Let’s a take a look.
Inflammation is one of the body’s natural defense mechanisms, and in healthy situations, it’s a good thing. However, chronic, out-of-control inflammation can not only be hazardous to your gut, joints, skin, gums, and lungs, it can also disrupt your sleep, trigger depression, and lead to heart disease, obesity and even cancer.
While Omega-3 fatty acids tend to be anti-inflammatory, Omega-6 fatty acids (which we now know are prevalent in vegetable oil) tend to be pro-inflammatory. Linoleic acid, specifically, has also been shown to cause inflammation.
Cholesterol and Heart Disease
Nearly one-third of adults in the United States have high cholesterol, and heart disease is the world’s most common cause of death.
One of the primary reasons vegetable oil is (erroneously) thought of as healthy is that it can lower total and LDL cholesterol levels. And if you think back to health class, you’ll recall that LDL cholesterol is the “bad” cholesterol. What isn’t often reported, however, is that vegetable oil has also been shown to lower HDL, or the “good” cholesterol. This is bad because high HDL levels are associated with a lower risk of heart disease.
And speaking of heart disease, vegetable oil appears more likely to cause it than prevent it, though evidence is admittedly a bit mixed. The common claim is that essential fatty acids help prevent heart disease. But this mistakenly lumps together both Omega-3 and Omega-6 fatty acids. When the two are consumed in balance, there’s indeed a protective effect. However, when people eat a disproportionate amount of Omega-6 (as found in vegetable oil), their risk of heart disease increased by 16 percent.
Cancer is a disease that many of us are all too familiar with, and among its many contributing factors could be consumption of vegetable oil.
As we mentioned, linoleic acid (heavy in vegetable oil) builds up in our fat cells and cell membranes. Over time, this damages important structures like proteins and DNA, and leads to the formation of carcinogenic compounds. Put simply, it contributes to increased cancer risk over time.
In fact, even the simple act of cooking with vegetable oil can contribute to our cancer risk. Compared to heat-stable fats like saturated and monounsaturated fats (think real butter, ghee, olive oil and coconut oil), cooking with vegetable oil forms large amounts of disease-promoting compounds. Some of these harmful compounds vaporize and may contribute to lung cancer when inhaled. In other words, just sitting in a kitchen where vegetable oils are being used may raise your risk of lung cancer.
So, based on all of vegetable oil’s potential dangers, I encourage you to purge it and all of the unhealthy oils (e.g., soybean oil, canola oil, corn oil, safflower oil, cottonseed oil, peanut oil) from your kitchen and replace them with some better alternatives. A few of my favorites are avocado oil, coconut oil and ghee. These are exceptionally healthy in the context of a balanced, whole-food based diet and have all the same applications. You won’t miss a thing, and your body will thank you!