Vegetable Oils – The Really Bad Fats



Who knew more than 50 years ago that we would still be talking about fats today, and whether or not they are bad for us? Although this debate has been ongoing for many decades, the hard work in research has finally started to pay off. Lipid (fat) scientists are now able to explain the reasons why certain oily foods may be toxic to the human body. Now, we actually have a reason to avoid fried foods for reasons other than the “They’re bad for you” pitch!

If you have ever heard that vegetables themselves are bad for you, then you probably would argue back! And in almost every other case you would be right to do this. However, the difference between whole-food vegetables and highly-processed vegetable oils is tremendous.

Before we dive too deeply into this, we need to talk about how the science wouldn’t be so significant if we didn’t love to cook so much. Cooking introduces the element of heat, which can improve the texture, flavor and consistency of food. But because cooking involves heat, fragile fats can turn toxic in the body when they are used in the cooking process. These toxic fats are called polyunsaturated fats, and the types of foods that contain the most of them are vegetable oils such as: canola oil, soybean oil, safflower oil, sunflower oil, grape seed oil and hemp oil.

 To explain, let’s take the sunflower for example…

Out in a crop field, where sunflowers would grow, the center of the flower head holds many small seeds protected by dark and thick shell casings. In this whole-food form, they are protected from both heat and air. When cracked open to eat, sunflower seeds are not exposed to these elements for a very long time before they are consumed and digested.

Now let’s take a look at what happens when sunflower oil is made, in a technique called cold-pressing. A machine extracts the sunflower oil from the seeds through crushing and filtering in order to separate out the bulk of the seed from the fatty oil substance. Now that this delicate oil is out in the open, and exposed to air and heat, its molecule structure slowly starts to degrade. This is done in a process called oxidation, which causes the oil to turn rancid.

An oxidized oil is toxic to the human body once it is consumed. Once a meal with these oils has been eaten, they form free-radical cascades in the body. Free radicals mutate our DNA and can cause damage to our blood vessel linings and our overall health.  A very large amount of toxic oils exists in the food industry. The vast majority of restaurants, grocery stores, bakeries and public food distributors (large and small) use these oils in fried foods, breads, salad dressings, pre-made deli dishes, and many other food products. It is even in some of our chocolate milks! By consuming these body damaging oils in so many different foods on a regular basis, we may be increasing our likelihood of developing diet-related diseases just for the sake of convenience.

However, there is good news when it comes to fats – there are oils other than polyunsaturated vegetable oils that can be used in cooking. These heat-stable fats have a much less detrimental effect on our health. Heat-stable fats/oils have stronger molecule structures to protect them from heat and oxygen. These fats are found in avocado oil, olive oil and yes, coconut oil. If we use these heat-stable fats in our everyday meals, then we can significantly reduce the damage that occurs in our bodies, and we may also improve the integrity of our health by eating foods that are cooked with these fats. One of the reasons restaurants and other food distributors do not use these higher-quality oils is because they can cost significantly more than inexpensive vegetable oils do. This is also one of the reasons fast food costs so little and the perceived value can be so much higher than it actually is.

Now that you know which fats are making a significant impact on health, I encourage you to do some experimenting in your own kitchen. Cooking foods in oils that are heat stable can often times produce a very comparable (if nearly identical) product when compared to foods that are cooked in vegetable oils.  The best part about all of this is you can still enjoy the foods you love! It is all about making the switch from more conventional to high-quality products. Before you know it, you’ll be one step closer to eating a higher-quality diet!

Jenna Moore, RD

Michele Bergh