Vegetable Oils: The Undervalued Health Crisis of Modern Nutrition
The dangers of vegetable oils have somehow flown under the radar for many years, recognized only by few, as seemingly if the world knew the truth they wouldn’t be found in nearly all food products available today. Their introduction to the food industry had little to do with human health and all to do with profit. They even disguised themselves as the “heart healthy” alternative during the distorted demonization of saturated fat in the 1960’s and that has stuck with us for all this time. Though, we must give credit to the industry’s marketing referring to them as “vegetable” oils, fooling us into believing these fats were somehow more natural and pure than those truly found in nature. From here on out we will refer to them as industrial seed oils.
This sad story began by turning what was then considered an industrial waste product (crude oil) into now what’s considered a “food” product. Enter Crisco - hydrogenated cottonseed oil developed in the 1880’s later to reach the cupboards of every American household by 1911. This article however, is not about the history of these oils, it is for you to understand why they should be avoided. Just know that the industry was driven by financial opportunities and not the well-being of consumers.
Examples of industrial seed oils:
Canola oil (or Rapeseed oil), Corn oil, Soybean oil, Cottonseed oil, Safflower oil, Sunflower oil, Peanut oil, Rice bran oil
So, what’s the issue?
They have no place in the human diet
The SAPIEN diet is focused on ancestral patterns of eating and without a doubt, industrial seed oils lack any relevance. These oils have been consumed by humans for under 100 years, a mere sliver in human history, with most only being introduced within the last 50 years. Industrial seed oils were not a part of human evolution and we are simply not biologically equipped to deal with them in our diet.
Today, soybean oil is the most consumed industrial seed oil in the US. In 1999, soybean oil accounted for over 7% of calories in the average American’s diet  despite only being considered “edible” in the 1980’s.
The diet-heart hypothesis – based on epidemiological studies from the 1960s – catapulted the industrial seed oil industry. Vilified for their high saturated fat content, traditional fats such as those in, and made from, animal products were largely replaced by these oils. The industry had everything they needed to market their oils as the “healthier alternative”.
Fatty Acid Profiles
Further considering ancestral eating, the fatty acid profiles of industrial seed oils are strangers to the body. They are composed primarily of polyunsaturated fatty acids (PUFAs) with a high proportion of omega-6 (linoleic acid) relative to omega-3 (EPA & DHA). It’s clear that this is a massive issue in the Standard American Diet (SAD), threatening the integrity of our cellular components, the very essence of what we are made up of. In this way, you literally are what you eat. Not only does the SAD lack quality sources of omega-3s, but it is excessively high in omega-6s due to the over-consumption of these seed oils, a destructive combo. The average American consumes a ratio of ~20:1 omega-6 to omega-3, when optimal health is typically achieved at a ratio closer to ~1:1.
It should be noted that omega-6 is in fact an essential fatty acid that we need to consume since our body doesn’t produce it itself, but the amounts we need are very small and covered with proper nutrition. Since the SAPIEN diet embraces fat, you do not need to worry about getting enough omega-6, it will happen naturally.
Susceptibility to Oxidation
Polyunsaturated fats, based on their chemical structure, are the least stable of all fats, meaning they are highly susceptible to oxidation. Lipid peroxidation creates toxic by-products which can contribute to inflammation  and DNA damage . Moreover, oxidized omega-6 PUFAs have been associated with atherosclerosis, neurodegenerative diseases, cancer, and more . These effects are exacerbated by high temperatures, making it even more dangerous to use these oils for cooking.
Taking a deeper dive, a high dietary ratio of omega-6 to omega-3 creates an imbalance in our cell membranes, whereby arachidonic acid (AA) predominates, occupying prime real estate that could otherwise be home to the omega-3s EPA and DHA. In general, AA is the precursor to pro-inflammatory mediators, namely the pro-inflammatory eicosanoids and cytokines. On the other hand, EPA and DHA (the omega-3s) are precursors to the anti-inflammatory eicosanoids, in addition to compounds that fight inflammation (e.g. resolvins and protectins). Altogether, excess omega-6 promotes inflammation while omega-3 fights inflammation.
How they are produced
Industrial seed oils are anything but natural. They require intensive extraction methods given their naturally low-fat content, unlike olives or coconuts that can be pressed into oil without such processes.
Prior to oil extraction, the material must be processed into “flakes”:
We are pretty confident that our ancestors didn’t have the machinery required such as this to get oils from their crops.
Following this preparation, the material is then exposed to hexane to dissolve the oil, heated to separate the oil from the hexane, degummed, refined, bleached (this is just with clay so it’s not as scary as it sounds), and deodorized to remove off-flavors and odors . The end product is then bottled to fill the shelves of our homes and grocery stores.
High heat, exposure to chemicals, and a man-made “food product” later, industrial seed oils have revolutionized our food systems for the worse and we can’t emphasize enough how important it is to remove them from your diet as best you can.
Blasbalg TL, et al. 2011. Changes in consumption of omega-3 and omega-6 fatty acids in the United States during the 20th century. Am J Clin Nutr. 93(5):950-62.
Kanner, J. 2007. Dietary advanced lipid oxidation endproducts are risk factors to human health. Mol Nutr Food Res. 51:1094-1101.
Lim, P et al. 2003. DNA damage and mutations induced by arachidonic acid peroxidation. Biochemistry. 42:15036-15044.
Tao, L. 2015. Oxidation of polyunsaturated fatty acids and its impact on food quality and human health. Adv Food Technol Nutr Sci Opin J. 1(6):135-142.
Muth MK, et al. 1998. Vegetable Oil Production: Industry Profile. Retrieved from https://www3.epa.gov/ttnecas1/regdata/IPs/Vegetable%20Oil_IP.pdf