January 9, 2019

Cooking Oils: why PUFAs need to Stay Out of the Kitchen & your Body.




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A post shared by ecofolks (@ecofolks) on Aug 10, 2018 at 5:00pm PDT

What do you like to cook with?

Could your oils be turning rancid from heat or is all that too much health food hype and worry? There is some new and surprising research to help us with these dinnertime decisions, which, over the years, add up to our health and longevity.

Saturated, Polyunsaturated, and Monounsaturated

First, let me explain the basics: we’ve all heard the terms saturated, polyunsaturated (PUFAs), and monounsaturated. Since the 1960s, the FDA has told us that saturated fats (animal fats, butter, ghee, and coconut oil) are unhealthy, and that polyunsaturated fats (vegetable seed oils) are best, while monounsaturated fats (extra-virgin olive oil) are healthy, but are not to be used for cooking.

These recommendations are extremely controversial and, while due for a revision, they are still receiving hard-line support from organizations like the American Heart Association. Let’s take a closer look at what oils are truly best for cooking.

PUFAs are extremely foreign to an ancestral human diet. The exceptions are omega-3 polyunsaturated fatty acids from fish (DHA and EPA) and ALA (alpha-linolenic acid) from nuts and seeds.

PUFAs are made from pressing oil from grains, seeds, and beans like sunflower, safflower, corn, and soybeans, which is possible only with extremely high pressure, heat, and a multimillion dollar press. Clearly, these seed and bean oils are a recent introduction to the human diet, but why are they bad for us?

The answer is that the oils in seeds, grains, and beans are volatile. They quickly and easily turn rancid from sunlight or heat. The clear plastic bottles of cooking oil we were told were so healthy have been heated to over 400 degrees Fahrenheit, degummed, refined, bleached, boiled, and deodorized, leaving the oil indigestible with no nutritional value

The Chemistry of Fats

Fats are carbon chains connected by either single or double bonds. When the bonds are saturated, the bonds between the carbons are single (with hydrogen atoms making up the remaining bonds). All the available bonds are taken, so the chain is saturated and therefore stable.

In an unsaturated fat, the chain of carbons is connected with double bonds. The single hydrogen bonds are replaced with an addition carbon bond, making a double bond between the carbons (which looks like: c=c=c).

If there are many such double bonds in a chain, it is called a polyunsaturated fat or PUFA. The double bond means that the chain of carbons lacks the hydrogen atoms that strengthen and stabilize the fat, rendering the fat unstable compared to its more stable, saturated cousin.

In a monounsaturated fat, the chain of carbons are mostly single bonds or saturated, except for one unsaturated double bond. Monounsaturated bonds are healthier because they are mostly stable and saturated (which would look like this: c-c-c-c=c-c-c).

When fat is saturated, the bonds are stronger, which is demonstrated by solidity at room temperature: think butter, ghee, or coconut oil. In the refrigerator, they get rock-hard, and in the heat, they melt. PUFAs (vegetable oils) are weaker unsaturated bonds, which are liquid regardless of the temperature and much more susceptible to damage. A monounsaturated fat (like olive oil) would be liquid at room temperature but would thicken up in the fridge, suggesting that the bond is stronger than a PUFA but weaker than a saturated fat.

So logically, the best cooking oils are the most stable saturated fats like butter, ghee, and coconut oil, which would be the most heat tolerant. That said, it is always wise to use lower heat whenever possible. Enough heat can damage or oxidize any oil, changing healthy fats into unhealthy fats.

Smoke Point

The smoke point is when oil is heated to the point of oxidizing and releasing toxic compounds. A smoke point chart can be misleading because the more refined and processed the oil, the higher the smoke point. Using the oil with the highest smoke point like almond, sunflower, or avocado does not take into consideration how highly refined these oils may be. Unsaturated fats or vegetable oils will generally have a higher smoke or flash point because they are more refined than the more stable, saturated fats.

In the lists below (adapted from the book Superfuel), you can see which oils are most saturated and therefore most heat tolerant. It lists the oils from highest to lowest percentage of unsaturated fats. Notice that high oleic sunflower oil is low in unsaturated fats but is extremely high in monounsaturated fats (81 percent), making it a heat tolerant cooking oil, like extra-virgin olive oil, which is 73 percent monounsaturated fat.

Percentage Polyunsaturated Fat in Cooking Oils (High to Low)

Safflower: 80%
Flaxseed: 74% (high in omega-3)
Grape-seed: 73%
Sunflower: 69%
Soybean: 62%
Corn: 59%
Cottonseed: 52%
Sesame: 43%
Canola: 28%
Peanut: 26%
Chicken fat: 18-23%
Olive: 11%
Lard: 11%
Palm: 9%
High oleic sunflower: 4%
Butter: 4%
Coconut: 3%

Percentage Monounsaturated Fat in Cooking Oils (High to Low)

High oleic sunflower: 81%
Extra-virgin olive: 73%
Canola: 65% (GMO product and highly refined and processed)
Peanut: 56%
Chicken fat: 48-50%
Duck fat: 50%
Beef tallow: 42-48%
Lard: 45%
Sesame: 41%
Butter: 30%
Corn: 27%
Cottonseed: 19%
Sunflower: 18%
Flaxseed: 17%
Grape-seed: 16%
Safflower: 11%
Coconut: 6%

To determine the best cooking oils, take the oils with the least amount of polyunsaturated fat and the highest amount of saturated fats (and a high monounsaturated fat content as well). Since high oleic sunflower oil is hard to find and sourcing is unreliable, I suggest cooking primarily with coconut oil, olive oil, and ghee. Ghee is purified butter with all the milk solids (which can be damaged by heat) removed.

The Magic of Olive Oil

Interestingly, new research has emerged suggesting that high-quality extra-virgin olive oil may be the best cooking oil of all because of its extremely high-polyphenol antioxidant content and relative stability in high heat. High-polyphenol content olive oil has been shown to reduce LDL damage and oxidation and raise healthy HDL levels. A recent study finds that both coconut oil and olive oil increase healthy HDL levels and reduce LDL.

Because all cooking has oxidizing effects, we should be cooking with the most stable saturated fats like ghee and coconut oil or a high-quality monounsaturated fat like extra-virgin olive oil, which carries powerful antioxidants to mitigate heat damage. Lipid researcher and author of Superfuel, Dr. James Dinicolantonio makes the case that high-quality extra-virgin olive oil may be the best cooking oil. He even suggests cooking meat coated with a thin layer of olive oil to protect the fats in the meat from oxidizing.

Sourcing the best olive oil can be tricky, as 60 to 90 percent of the oil sold in grocery stores and used in restaurants may have been adulterated or diluted with PUFAs or cheap, unhealthy, unstable vegetable seeds oils. (I will get to my favorite olive oil shortly.)

New Research on Cooking with Olive Oil

There has been much confusion around the safety of cooking with olive oil, as many studies found the smoke point of olive oil to be quite low. New research suggests that high-grade extra-virgin olive oil is stable at high heat and has a smoke point approaching 400 degrees Fahrenheit.

Most smoke point tests have been done on low quality, likely adulterated olive oils purchased off a supermarket shelf. Studies done on verified high-quality extra-virgin olive oil have demonstrated low acidity, more stability, higher smoke point, higher resistance to oxidation, and longer shelf life compared to the inferior counterfeit oils on the market.

The stable properties of a high-quality extra-virgin olive oil are primarily due to high content of naturally occurring antioxidants called polyphenols. Refining the oil or taking lower quality oil from later stages of pressing significantly reduces the polyphenol content of the oil, which is why getting the highest quality olive oil is so crucial. In one study, certain store-bought olive oils had as much as five times the polyphenol content as others.

In a 2015 study on cooking with extra-virgin olive oil, researchers found that frying with olive oil and water preserved the antioxidant content of the oil and the vegetables that were cooked and, in fact, boosted their antioxidant content.

Guarantee the Best Olive Oil

When sourcing olive oil, look for a harvest or press date. It is ideal to ingest the current year’s harvest.

If it is a California olive oil, make sure it is certified organic by California Certified Organic Farmers (CCOF) and certified extra-virgin by the California Olive Oil Council (COOC).

If the oil is from Italy, look for a DOP seal (Protected Designation of Origin), which means the olives are from where they say they are.

Impressive Olive Oil Facts

  1. Seven tablespoons of high-polyphenol olive oil raised HDL levels by three percent.
  2. Two tablespoons of high-polyphenol olive oil significantly improved endothelial function.
  3. High-polyphenol olive oil enlarged HDL cholesterol particles, making them more heart-healthy.
  4. High-polyphenol olive oil lowered blood pressure in adults aged 55 to 80.
  5. High-polyphenol olive oil has been shown to cause toxic and unhealthy cells to self-destruct instead of divide.
  6. New studies suggest that high-quality extra-virgin olive oil may protect against cognitive decline, bone density concerns, skin aging, and premature death.

I hope I’ve given you some food for thought next time you pick up your skillet. Treat your body right by cooking with ghee, coconut oil, or high-quality olive oil. Your food will taste better, too!


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