From The Desk of Josh Gitalis

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Vegetable Oils

Fat is one of the most misinterpreted topics in the nutrition field and it’s an area that I am frequently asked about. We are still suffering the fallout from years of health advocates promoting low-fat this and low-fat that, when in truth all of that low-fat advice has proved to be completely wrong.

Often in the health field, we are faced with all-governing statements that try to establish clear-cut rules like, “All fats are bad.” More frequently, the truth lies in a more complex ruling. In this case, there are fats that are good, and fats that are bad. But how do we know which ones to choose?

Our brains are 60% fat, and every single one of the trillions of cells in our body is surrounded by fat. We build these tissues with whatever fat we consume, so the types of fat we select are incredibly important.

Today I’d like to reveal the dangerous side of white vegetable oils and show you how and why these ubiquitous fats are potentially damaging our health. Armed with this knowledge, you’ll be fully equipped to make better decisions at the grocery store to support your health.

The Dangerous Side of Vegetable Oils: The Processing

Clear white vegetable oil, like white sugar, white flour and white salt, is devoid of the nutrients we need to properly metabolize it. There is a complex process that converts these oils from a healthy whole oil to a health-degrading white oil. Here is what happens in oil processing *:

Step 1: Obtain the seeds, nuts or beans.

Step 2: Extract oil (either by mechanical pressing or chemical extraction). Chemical solvents like hexane or heptane may be used to extract the oil and the oil is distilled at 150 degrees Celsius. During this step, the oil loses protein, fibre, vitamins and minerals.

Step 3: Degumming. In this step, oil producers remove the phospholipids – fats that line our cell membranes – as well as calcium, magnesium and iron. One specific fat extracted during this process is called lecithin, a crucial lipid for brain health and memory.

Step 4: Refining. The oil is mixed with a corrosive called sodium hydroxide to further remove phospholipids and free fatty acids.

Step 5: Bleaching. During bleaching, filters remove pigments like chlorophyll and beta carotene. Cholophyll is the plant pigment responsible for photosynthesis, and it has anti-inflammatory and immune-boosting properties. Beta carotene is the pre-cursor to Vitamin A, which is important for our vision, skin and immunity.

Step 6: Deodorizing. By this point, all of the oil processing has impacted its smell and taste. If you were given a teaspoon of oil after Step 5, you definitely wouldn’t want to consume it. That’s why oil producers need to deodorize the product by heating it high temperatures (240-270 degrees Celsius) and filtering out the strong odours and flavours. During this process we lose Vitamin E, an antioxidant that protects our cells from damage.

Before the oils are ready to be sold, preservatives are added to boost shelf life.

Step 7: Hydrogenation. During this step, liquid oils are chemically altered so they are semi-solid or solid. This extends shelf life and makes inexpensive vegetable oils spreadable like butter. Unfortunately, our bodies aren’t able to recognize and use these fats, which can lead to deleterious health effects – which we’ll get to momentarily. Not all vegetable oils go through this process, but many of them do.

* Reference: Erasmus, Udo. “Chapter 16: From Seed to Oil.” Fats That Heal Fats That Kill: The Complete Guide to Fats, Oils, Cholesterol and Human Health. Burnaby, BC: Alive, 1996. 93-99. Print.

Steps in oil processing

As you can see, we start off with a whole food and through oil processing we end up with something that is the complete opposite. Instead of nutrient-richness, what we’re left with is a processed, non-food product that can be damaging to our health.

How Vegetable Oils Affect Our Health

Clear white vegetable oils impact our health and wellness in a variety of ways. Here are some important things to consider.

Trans Fats

You’ve probably heard a lot about trans fats in the media and they are vilified for good reason. Trans fatty acids occur when liquid oils are hydrogenated at high temperatures. Normally, the chemical bonds in liquid, polyunsaturated fats are quite fluid and floppy. During hydrogenation, those chemical bonds are packed with hydrogen atoms. This transforms the fat into something stiff, solid and shelf stable. Hydrogenation turns the fat rancid and makes it into a strong free radical. Free radicals promote cancer and heart disease.

Trans fats have been well studied and their negative health effects are numerous, including:

They are associated with systemic inflammation in women, as well as weight gain.

In the United States, the FDA has banned trans fats and companies must remove them from their products by 2018. In Canada, where I am, trans fats must be listed on labels but there is no ban in place as of yet.

The Omega 6: Omega 3 Ratio

Omega 3 and Omega 6 fatty acids are essential fats that our bodies need for brain health and development, nervous system health, hormone production, cellular health, skin health and more. These key fats must be obtained from the diet in the proper balance

The ideal ratio of Omega 6 to Omega 3 is between 4:1 and 2:1. Unfortunately, many of us consume far too many Omega 6s in a ratio that is closer to 20:1. Excessive Omega 6 consumption can lead to inflammation and promote a variety of diseases such as cardiovascular disease, cancer, arthritis, Alzheimer’s, inflammatory bowel disease and other autoimmune diseases.

Processed vegetable oils are much higher in Omega 6 fatty acids, which can lead to a pro-inflammatory response throughout our bodies.

Genetic Modification

The source of many vegetable oils – corn, soybean, cottonseed, palm, rapeseed, safflower, etc. – are highly genetically modified foods.

Genetically modified organisms are a burden on the immune system. Our immune system has developed and evolved over thousands of years. When we introduce a genetically modified food to the immune system, it’s like speaking Chinese to an English-speaking person and expecting them to understand it. Our immune system doesn’t recognize the language of “genetically modified” and, as a result, identifies it as foreign and executes an immune response.

GMOs are linked to a range of health issues, including:

  • Allergic reactions
  • Reproductive issues
  • Liver problems
  • Cancer
  • Antibiotic resistance – persistent use of GMOs, which are bred to be impervious to chemicals that will kill them, may impact the effectiveness of antibiotics in humans.

Genetic modification is a controversial topic, but at this point we don’t have enough long-term data that conclusively proves that GMOs are safe. If we can reduce our exposure by eliminating vegetable oils, we’ll be better off in the long run.

Processing, Additives and Preservatives

We’ve already discussed the extensive processing involved in oil production that transforms it from food into something that is essentially non-food.

A popular vegetable oil product is margarine and other ‘butter-like’ products. Margarines not only have these unhealthy oils, but also contain added preservatives, emulsifiers, colours, flavours, sodium and synthetic forms of vitamins that aren’t easy for our bodies to absorb and use.

You can read more about the negative health effects of margarines like Becel here.


Vegetable oils, if they haven’t been completely hydrogenated, will contain some polyunsaturated and monounsaturated fats. These fats are sensitive to heat, light and air, making them more unstable and a poor choice for medium or high heat cooking. Unfortunately, that is what most households, restaurants and companies use them for.

Nowadays vegetable oils have omega 3s added to them for additional health benefits. But when we cook with omega 3s on high heat, they are destroyed and create free radicals – so not only are the benefits lost, but new harmful toxins are created.

How to Choose Beneficial Oils

So what oils should you consume?

  • Choose oils that are found in dark glass bottles.
  • Buy organic, cold-pressed oils.
  • For high heat cooking use coconut oil or ghee; these are very stable at high temperatures.
  • Eat plenty of nuts and seeds, raw and unsalted.
  • Make your own salad dressing with flax or olive oil.
  • For the visual learners among you, consult this handy infographic.

Every choice we make either contributes to disease or builds our health. By eliminating dangerous vegetable oils from our diet, we can support the latter.