On a particularly masochistic day, I approach a stranger on the sidewalk and ask for the key to a healthy diet. I quickly find myself trapped in a one-way treatise on fat, carbs, meat, sugar, and for some reason, politics. Already regretting this exercise, I push on.
“What about oils?”, I blurt out.
“Oh, I try not to use too much,” the stranger replies.
“That’s it?”, I ask, surprised by this uncharacteristic brevity.
“Well… oil is fattening, right? Honestly, I haven’t thought about it much.”
Having heard enough, I excuse myself and continue on with my fictional day.
I suspect oil is so often overlooked by otherwise health-conscious consumers for good reason: it’s invisible, and often tasteless. Order a plate of food at a restaurant and many elements are easily discernible—the portion of fruit, vegetable, meat, grain. A smart palette can tease out other important nutritional qualities like sugar and salt content. But you might be surprised to learn that in many instances, the majority of calories on that plate comes from added fats and oils used for cooking, dressing or thickening .
If fats and oils make up the largest portion of our calorie consumption, we better pay attention to their quality.
Vegetable Oil: Good Name, Bad Choice
Speak to 100 nutritionists and you’ll find just one thing they can all agree on: vegetables are healthy. The same cannot be said for the tricky imposters we call “vegetable oils”.
While vegetable oil technically includes any oil extracted from a plant source, in common usage it refers to industrial seed oils like soybean, corn, rapeseed (a.k.a. canola), cottonseed, safflower and sunflower.
The story behind the invention, propaganda and ubiquitous spread of industrial seed oils—in turn fascinating and upsetting—is too long for this post. Here is a concise summary.  For now, let’s look at why these oils are so harmful and what we can do about it.
Fatty acids come in three structural variants: saturated, monounsaturated and polyunsaturated.
In saturated fat (SFA), all carbon bonds are paired with hydrogen atoms, making them extremely stable when exposed to oxygen or high heat.
Monounsaturated fat (MUFA) contains one double bond in its fatty acid chain, while polyunsaturated fat (PUFA) contains more than one double bond, making it the least stable and most vulnerable to free radical damage and rancidity.
Deeper down the rabbit hole we find essential fatty acids (EFA) – “essential” because the body cannot produce them. The two primary EFA’s are Omega-3 and Omega-6. Omega-3 is generally anti-inflammatory and Omega-6 pro-inflammatory. Both are required for optimal functioning, but balance is key. Omega-3’s are found mostly in fish and nuts, while grains and most vegetable oils are chock full of Omega-6. Traditional human diets trended toward an equal ratio of Omega-6 to Omega-3, but modern Western diets average a 20:1 ratio, likely contributing to the elevated inflammation levels many people find themselves battling.
Phew…let’s take a deep breath and look at how this applies to the oils in our diet.
Industrial seed oils are comprised largely of a PUFA called linoleic acid. Linoleic acid is infamously fragile, breaking apart, oxidizing and becoming inflammatory when exposed to heat.
On the other end of the spectrum, oils like coconut, palm, olive and avocado (in addition to animal fats like butter and lard) are rich in stable SFAs or MUFAs, and are also packed with antioxidants that further protect them from damaging oxidation.
The process of extracting oil from a seed requires the use of high heat, deodorizers, de-gummers and chemical solvents like hexane. The resulting oil likely arrives in the bottle at least partially rancid. My choice of fats comes straight from animals or undergoes far more gentle, mechanical extraction.
The heavy processing required to create industrial seed oils results in bland, tasteless oil. Gently extracted oils like olive and coconut retain the rich flavors of the plants, enhancing rather than hiding behind the foods they accompany.
The case against vegetable oil is strong and varied. So why is it that nearly every restaurant in the US (and increasingly, the world) chooses to cook with such inferior product? The answer is part clear and part subtle. First, the obvious: industrial oil is cheap. It is essentially a byproduct of the heavily subsidized industrial agricultural system that shoves corn and soybean into every corner of the Western diet. Oil is invisible and unlisted on menus, and restaurants are always on the lookout for cost-saving measures.
The second (and in my opinion more salient) reason for the ubiquity of these subpar oils is simply the lack of awareness on both the food service and consumer end. When documentaries began to expose the horrors of industrial animal farming, consumers took note and started demanding more humanely raised meat. Food purveyors have responded to that demand, and the growth of grass-fed and pastured meat has been exponential. With added fats and oils comprising the invisible majority of Western diets, it behooves us to pay more attention to where they come from and what they do to our bodies. Start asking your favorite restaurants what oils they use, and they will take note. Buy packaged products that use better oils. Help start an invisible revolution!