Are Healthy Oils Turning Your Food Toxic?


Are Your Heart Healthy Oils Turning Your Food Toxic?

Over the past decade, Americans have traded in saturated fat for their heart healthy counterpart, unsaturated fats. At its core, this is a giant step towards better health. However, when not stored correctly and if heated past their smoke point, unsaturated fats can actually become even more dangerous to your health.

In order to understand this, let’s take a quick step back to High School chemistry (I promise this will be quick!).  The difference between a saturated fat and unsaturated is the amount of hydrogens on the fatty acid chain. As you can see in the image, saturated fats are fully “saturated” with hydrogens. This makes the fat more stable and it’s the reason why it is typically solid at room temperature. Unsaturated fats have some double bonds making the fat a bit more fragile and fluid. Unsaturated fats are typically liquid at room temperature.


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Although the fluidity of the unsaturated fat makes it flexible when passing through your body, it is very fragile and susceptible to oxidation and can quickly become rancid. From a taste standpoint, rancid oils are as appetizing as they sound. From a health standpoint, rancid oils can speed up cellular aging, increase inflammation and are potentially carcinogenic.  (End of the chemistry lesson!)

In order to protect the oils and make sure they are improving rather than damaging your health, there are two main factors to consider – storage and smoke point.

Storage of Cooking Oils

Unsaturated oils are broken down by light and heat and typically have a much shorter shelf life than saturated oils. Here are the most important things to consider when storing your oils:

  • Choose oils in a tinted bottle and store in a dark cabinet to avoid exposure to light.
  • Store away from the stove in a cooler area of your kitchen. Polyunsaturated oils (such as flaxseed) are best stored in the refrigerator.
  • Check the expiration date and make sure to get rid of the oil as soon as it’s expired.
  • Avoid huge bulk versions of oil. I know that it seems cheaper but the oil will most likely go rancid before you use it and you might be tempted to keep it rather than throwing it away.

Smoke Point of Cooking Oils

The smoke point of cooking oil is the temperature at which the oil will start to smoke on the stovetop. This signifies that it has been heated past its safe temperature, is chemically breaking down and becoming rancid. Here is a table with the smoke points for the most popular cooking oils as well as the types of cooking they are best used for.


Different cooking oil smoking points

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Healthy oils can be both a way to pack in nutrients and flavor to your meals. Make sure you are both storing and cooking with them correctly to get the most health benefits and protect both you and your family.



Tara Coleman

Tara Coleman is a Clinical Nutritionist with a private practice in San Diego, CA. She speaks nationally on the topics of health and nutrition and has been cited as a nutrition expert by media such as NBC, FOX, SELF, Cosmopolitan and Dr. Oz The Good Life. Download her FREE 4 Step Nutrition Quick Start Guide and start feeling better today!

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