O.k., it looks like I’m going to break up my Vegetable Oil & Sugar post into two posts, one on vegetable oil and the other on sugar. There’s just so much information. I’m going to do my best to condense the information that I learned from Catherine Shanahan in her book Deep Nutrition. The best thing to do would be to read the book but if you don’t have time I hope my condensed version will at least get at the “whys” – why vegetable oil is bad, why we should avoid it 100% of the time.

The section on Vegetable Oil in the book Deep Nutrition starts off with an interesting question. If an unknown lipid (fat) scientist proved that the fake fat (trans fats) found in margarine, and pretty much all other processed and refined foods found in the grocery store was a deadly toxin and presented this information to congress would that toxin be removed from our food supply? Sadly, the answer is no.

Back in 1977 Dr. Mary Enig (read more here) presented scientific findings to congress with a warning that the trans, found in hydrogenated oils were dangerous. It took decades before the American public was warned of the dangers of trans fats and that only happened after trans fats were outlawed in European countries.

Why did this take so long? Catherine Shanahan suggests that, “scientific discoveries that are incompatible with commercial interests have a tough time making it to the papers.” She cites cigarettes and asbestos as two other examples.


Now, on to vegetable oil – where does it come from?

“Vegetable oil is the lipid (fat) extracted from corn, canola, soy, sunflower, cotton-seed, safflower, rice bran and grapeseed.”

Vegetable oil is made up of polyunsaturated fats (PUFAs). Polyunsaturated fats are heat-sensitive, which means when they are heated they “turn into toxic compounds including, trans fats”. “If we could somehow get canola oil out of the seed without exposing it to heat, it would be good for us. But nobody can. (Shanahan)”

“This means that vegetable oil, and products made from vegetable oil, contain trans fat – even when the label seems to guarantee them trans fat free.” (more on this below)

One thing that was cleared up for me while reading Catherine Shanahan’s information about vegetable oils was why everyone recommends seeds as a healthy snack but seed oils are bad.

“Unfortunately, refining these oils ultimately destroys both healthy PUFAs and their complimentary antioxidants, converting them into distorted, unhealthy molecules. So what was healthy in the seed isn’t healthy in the bottle.”

The processing of the seeds into vegetable oil creates mutated fat molecules – “trans fat, cyclic hydrocarbons (carcinogens) and oxyphytosterols (highly damaging to arteries)” (Shanahan). Natural fats are safe to eat so before the seeds are processed and refined and their fats mutate they are safe to eat as a healthy whole food snack.

We have all heard that trans fat is bad and now we know that vegetable oils are a primary source of trans fat, a man-made fat that challenges our bodies metabolically. The problems that can arise from a diet high in trans fat (any trans fat is too much) can “range from neurological problems to cancer” (Gedgaudas). You can read a list of the adverse effects of trans fats here (the whole article is good but you can scroll down to “Bad Fats” for the list).

O.k., so I think we get that trans fat is BAD. Catherine Shanahan goes one step further. She says, the real trouble start after you eat the toxic trans fat.

“The real trouble has to do with the fact that after you eat these distorted, mutated fatty acids, they can reproduce inside you.”

Catherine Shanahan states that the mutated, bad PUFAs you ingest through the consumption of vegetable oil or products made with vegetable oil use free radicals to turn normal, healthy PUFAs in your body into bad, dangerous PUFAs “at the rate of billions per second”. That does not sound good.

What are free radicals? This is how they are described in Deep Nutrition:

 “Free radicals are high-energy electrons that are involved in every known disease. They behave like molecular radiation, burning everything with which they come into contact, inside your body or out.”

Again, that sounds really bad.

Catherine Shanahan refers to the bad trans found in vegetable oils (mutated, bad PUFAs) as MegaTrans because of their ability to damage normal PUFAs in your body on contact. Some of the technical names for “MegaTrans” are peroxidized fats, lipoxygenases, oxidized fat, lipid peroxides, and lipid hyroperoxides.

So, where do the free radicals that the MegaTrans team up with come from? Heat.

“In the frying pan, MegaTrans reacts with oxygen to generate one free radical after another. Frying in vegetable oils doesn’t so much cook your foods as blast them with free radicals – fusing molecules together to make the material solid. Chemists call this series of reactions a free radical cascade.”

“Just a little MegaTrans in the bottle of canola oil can become a lot of MegaTrans after you – or the cereal/donut/frozen dinner manufacturers – cook with it.”

Vegetable oils are bad. They are a primary source of trans fat. They cause chaos and damage through out our bodies. To really understand how the damage is done you are going to have to read Deep Nutrition or another book of your choice that explains the process. It would take me days to write about it and my information wouldn’t be even close to as clear as what you can learn from an expert.

The last thing I want to say is read food labels. The most important part of the food label, when it comes to trans fat is the ingredient list.

The FDA guidelines only require food manufacturers to list trans fats if there is .5 gram or more in 1 serving. That means, if there is .49 grams in a single serving they can state in bold letters on the front of their packaging that the item is “Trans Fat Free”. Have you ever noticed how ridiculous a “serving size” is? Most people, especially when it comes to processed foods eat more than a single serving at one time. This means, they think they aren’t eating any trans fats when in fact they could easily be ingesting several grams. Here is a link to the FDA’s page on trans fat labeling guidelines.

Here is a list of some well know “trans fat free foods” that actually have trans fats (source)

  • Microwave Popcorn
  • Saltine Crackers
  • Ritz Crackers
  • Special K Bars
  • Girl Scout Cookies
  • Animal Crackers
  • Sugary Breakfast Cereal

*I just checked the old microwave popcorn and cereal in my pantry. None had trans fats and I’m happy to report the oil used was palm oil.

So, if it says 0 trans fats how can you tell if the product actually contains trans fats?

“Consumers can know if a food contains trans fat by looking at the ingredient list on the food label. If the ingredient list includes the words “shortening”, “partially hydrogenated vegetable oil” or “hydrogenated vegetable oil,” the food contains trans fat. (source)

The whole point of this post was to convey the dangers of vegetable oil. Hopefully you all have the same feeling I had when I finished reading about vegetable oil in Deep Nutrition – never eat vegetable oil and make sure to read labels and not buy/eat anything made with vegetable oil. There are far better things to eat, no need to include a toxic substance in your diet when you can make the choice not to.

I haven’t cooked with vegetable oil for almost a year. Reading labels has become my obsession. I scan everything for vegetable oil. Turns out, it’s in EVERYTHING! I bought some “made fresh” pesto at Whole Foods thinking it couldn’t be bad – wrong. They used canola oil, not olive oil. And, as I’ve mentioned several times because it really irks me, most of the pre-made food at Whole Foods has canola oil in it.

If you are wondering what you can cook with since you just threw out all of your vegetable oils you can read my post on Fats for some healthy alternatives.

Eat Well, Feel Good, Have Fun!

I’ll try and tackle sugar next.

Book sources:

Deep Nutrition by Catherine and Luke Shanahan
Primal Body, Primal Mind by Nora T. Gedgaudas

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4 Responses to Trash The Vegetable Oil

  1. amyd says:

    So, what about olive oil? Is it considered a vegetable?
    Very good, though disturbing, article. Thanks, Amy!

  2. amy says:

    It comes down to oxidation. Saturated fats are the best to heat because of the way they are shaped, no way for oxygen to sneak in and mutate. Monounsaturated fats have room for 1 oxygen molecule to sneak in (mono) but it’s not easy for that oxygen to get in there and really mess them up. Olive Oil is a monounsaturated fat so it can be heated but if you are going to use high heat you should always use a saturated fat that can’t be mutated and damaged by oxygen.

    • amyd says:

      Thanks, Amy. I often have a “problem” with getting my fats too hot & they smoke (beef tallow & coconut oil is what I use). I think it’s cause I have a hard time getting the heat set just right for the pan, then I’m pretty bad about turning the pan on to heat & getting busy chopping or the like and next thing I know it’s smokin’!

      I haven’t yet tried palm oil, but want to at some point.

  3. Craig Abernethie says:

    It is best not to fry or cook with Mono’s such as Olive oil as stated above. I think Coconut oil and Ghee (clarified butter I think) is the best to cook with. I also think Palmitic oil is very good from a stability to heat point of view. I do also think frying or deep frying is very detrimental to any fats in the Food because the temperature corrupts those fats “on the inside” of the Food concerned, so it’s probably just best not to do either of those processes. Happy Trails.

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