Fat is without doubt one of the most controversial and confusing components in our diet. Is it good for you or isn’t it? Does it make you fat, or doesn’t it? How about cholesterol? Beware of saturated fats, or not? In the past 50 years or so we have gone from eating a diet relatively high in fat to eating a diet low in fat and we are now back to understanding that fat is an essential macro nutrient and an integral part of our diet. Our bodies need it for energy, growth and development. It cushions our organs and it helps with the absorption of the fat soluble vitamins A, D, E and K. Fat gives flavor and texture to our food and as it takes longer to digest it helps us feel satisfied longer.
Although there is consensus amongst health experts and scientists alike about the dangers of eating trans-fats, not everyone seems to be on the same page when it comes to saturated fats and more importantly vegetables oils. Through personal research as well as experience I have come to a few conclusions about the consumption of vegetable oils. These views are backed up by many experts in the field of nutrition but have still not been widely accepted and understood by all. In this article I will explain what vegetable oils are and why they are best left out of our diets.
What are vegetable oils?
Vegetable oils, or also called industrial seed oils, are oils extracted from seeds such as corn, safflower, sunflower, grape seeds, canola, soy, and cottonseeds. They mostly contain omega 6 poly-unsaturated fatty acids (PUFAs). Omega 6 fatty acids are critical for healthy brain function, metabolism, growth and development and because they are not made by our bodies they are an essential component in our diet. The problem with omega 6 fatty acids lies in over-consumption which promotes inflammation. I will go into more detail on this later.
The vegetable oil extraction process
Until the early 1900s vegetable oils were practically non-existent in our diets. When new chemical extraction processes were invented these oils were allowed to be extracted more easily and cheaply making them an increasingly popular oil to cook with.
Unlike for example olive oil, vegetable oils can’t be extracted just by pressing the seed. They have to be removed chemically, deodorised and altered. Most commercial seed oils are processed under high heat, pressure and with the help of industrial solvents.
There are many problems associated with this extraction process which I will discuss next but first and foremost I would like to point out that having undergone all this, vegetable oils can hardly be called a whole, natural food anymore. And eating a whole, natural food diet is what I consider to be the basic requirement for achieving excellent health.
Oxidation and free radicals
Whole oily seeds have inbuilt compounds in the form of anti-oxidants that protect them from oxidation. You can compare this to apples which have a skin protecting them. Once you peel that apple it takes only minutes for the insides to start turning brown which is through the same oxidation process. Once seeds have gone through the oil extraction process most of the protective anti-oxidants are removed, making the oil vulnerable to oxidation and rancidity. Furthermore the high heat involved in the chemical extraction process speeds up this process.
Oxidation leads to the formation of free radicals which are highly reactive molecules that in small amounts play an essential role in the body’s biological functions such as immunity and cellular repair. Too many free radicals lead to an imbalance which causes damage to cells. It has been linked to Alzheimer’s, high blood pressure, cancer and inflammatory conditions.
Cooking with vegetable oils
Bottles of industrial seed oils, partly oxidized and rancid and extremely vulnerable, promoted as healthy, are now waiting for us to cook with.
Cooking and especially frying with these oils at high heat causes further oxidation and exposes your food to all these free radicals, essentially fusing molecules together in what chemists also call a free radical cascade. Furthermore the cooking process destroys complex nutrients.
Once consumed, oxidized PUFAs have the ability to damage normal fatty acids in your bloodstream at an unbelievably high rate, turning them into what Dr. Cate Shanahan called Mega Trans. In her book “Deep Nutrition” she explains in detail the effect of eating vegetable oils on our bodies and how the Mega Trans eventually lead to inflammation, arterial damage and heart attacks.
Omega 6 overdose
In the early days of human existence where our ancestors obtained their food through hunting and gathering, fats provided the largest source of energy. In those days omega 6 fatty acids were consumed in small amounts and at about the same ratio as omega 3 fatty acids, another essential, healthy PUFA that we all need for healthy brain function, growth and development and that are anti-inflammatory in nature. The ratio of consumption of Omega 6 to Omega 3 in those days was around 1:1 or 2:1. Nowadays our omega 6 intake is disproportionally large compared to our omega 3 intake. The current ratio has been estimated to be in the region of 12:1 and upwards.
Vegetable oils are simply everywhere. In most processed foods, in the foods we eat outside and in the foods we cook at home because these same oils have been touted as “healthy”. According to scientists, it is this shift in fat composition in our diets that has played a significant role in the increase of inflammation related conditions such as obesity, insulin resistance, heart disease, diabetes and cancer.
How to reduce your consumption of vegetable oils
1. Avoid eating processed foods.
Commercially produced chips, biscuits and other processed foods are all made with industrial vegetable oils. Similarly, french fries and other deep fried foods are cooked in these unhealthy oils. By avoiding these foods you can reduce your exposure to oxidized, rancid vegetable oils as well as substantially reduce your omega 6 intake.
2. Choose healthier fats for cooking
Get rid of those big bottles of industrial vegetable oils. No more canola, sunflower, safflower, soy, corn, grape-seed or cottonseed oils. Instead cook with extra virgin olive oil, ghee or coconut oil. Long thought to be unhealthy because of their high levels of saturated fats, ghee and coconut oil have been rediscovered by health experts world over because of their high levels of saturated fats! Please read my article on saturated fats to understand why: “The Truth About Fat.”
3. Bring your omega 3 fatty acids back in balance.
They are an essential component in our diet, supporting healthy brain function, growth and development and countering the inflammatory 6 omega fatty acids with strong anti-inflammatory action.
Eat fatty fish such as mackerel, sardines and salmon. Although there are some vegetarian sources of omega 3s, such as walnuts, flax seeds, chia seeds, hemp seeds etc. their conversion to a usable form in our bodies is relatively low.
Because most of us don’t eat fatty fish on a daily basis, it is a good idea to supplement with a high quality fish oil or a plant based oil if you are vegetarian to ensure adequate intake of omega 3.
I hope this article helped clear up some of the confusion around the consumption of vegetable oils.
Be Well.
Monique
