“Nutrition is a six-way teeter-totter. Have you ever tried to balance such a device?”
-C.C Furnas, Man Bread and Destiny: The story of Man and his Food, 1937
Fat comes in many varieties, including saturated, monounsaturated, polyunsaturated, cis and trans
I am a huge advocate of fat because it is vital for any healthy organism to thrive. However, not all fat is created equal. If you have a choice, consume fats that are mainly saturated and monounsaturated. So we’re talking steaks and coconut oil here. An example of polyunsaturated fat is canola oil and soy oil. Besides being highly processed, these oils are easily oxidized both inside and outside of the body, which turns them rancid, and in turn, you rancid. They are called polyunsaturated because they contain more then two double-bonded carbons. A saturated fat has no double bonds and a monounsaturated fat only has one double bond. The terms cis and trans simply refer to the position of the hydrogen in reference to the double-bonded carbons. If the hydrogens are on the same side of the carbon, then they are a cis-fat. If the hydrogens are on opposite sides of the carbon, then they are called a trans-fat.
Cis Bond
Trans Bond
Trans fats have gotten a bad rap recently and most people assume they are all created equal
However, they are not, and it is more nuanced then that. It all depends on which carbon the trans bond occurs. Trans fats occur naturally on the 11th carbon of certain animal fats.1 This is not a problem because our body possesses an enzyme perfectly capable of breaking that bond and converting that trans fat into something useful, CLA (conjugated linoleic acid). However, the vast majority (over 90%) of fats found in nature are cis fats, therefore, the bulk of our enzymes and fat metabolism systems are designed to deal with cis bonds. This becomes a problem when food manufacturers use a process called hydrogenation to turn polyunsaturated fats into saturated fats. This creates trans bonds on the 8th, 9th, 10th, 11th and 12th carbons
Our enzymatic systems are not capable of metabolizing these bonds properly which leads to issues, including structural problems with cell membranes and deficiencies in essential fatty acids.2
Food manufacturers were forced to do this when saturated fats were demonized, starting in the 1970’s, so they had to remove most of the saturated fats in their products to appeal to public demands. However, using polyunsaturated fats yielded poor results in both taste and texture of their food. The benefits of saturated fats is that structurally, they are straight, and they can stack perfectly, creating a crystalline structure, which we perceive in the food as having a good consistency and mouth feel. Polyunsaturated fats are not straight. Each double bond inserts a bend in the fat, so they cannot stack together tightly, resulting in food that is oily and does not have the desired consistency. Through hydrogenation, the cis bonds are forcibly shifted to the trans position which straightens out the hydrocarbon chain. Therefore, it’s not that all trans fat are bad- it depends on where the trans bond occurs on the carbon chain.
As stated earlier, fat is necessary for a healthy individual to thrive because many of our key organs and systems rely predominately on fat
Our myelin sheath, which insulates our nerves, is made primarily of fat. The primary fuel for our heart is fat. The key ingredient in every single one of our cellular membranes is fat.
At least fifty percent of our cellular membrane is fat with cholesterol mixed in to provide structure and to act as an antioxidant in order to resist reactive oxygen species.3
Every organelle in our body is surrounded by a cellular membrane, called a phospholipid bilayer, which is made up of fat, cholesterol, and phospholipids. Our bodily functions all work because we are able to separate the inside from the outside and that’s all due to healthy, intact cellular membranes. It gives our cells the flexibility needed to thrive. It has been shown that the major fat consumed through our diet will be the primary source of fat used to construct our cellular membranes. This is a key reason why you want to consume saturated fat. A carbon that is bonded four times is a stable carbon, which is the case in saturated fats. These happy carbons are chemically stable, meaning they resist oxidation (loss of electrons or addition of oxygen) very well. However, if you consume more polyunsaturated fats, (vegetable oils, canola oil, soy oil) your cell membranes will be made up of these types of fats and each “poly” bond is a point of weakness. This means that not all the carbons are bonded to four separate entities, resulting in the carbons being easily oxidized. An oxidized cell can become damaged and no longer function properly, leading to cell death. This process is called lipid peroxidation. It has three steps, which include initiation, propagation, and termination. In the initiation step, a free radical (reactive oxygen species) comes along and steals a hydrogen from the double bond location, creating a unstable lipid radical. Then the second step, propagation, occurs. Since this lipid is chemically unstable, it reacts quickly with oxygen to create another radical called a lipid peroxyl radical. This radical reacts with another normal free fatty acid in the cell, turning it into another unstable lipid radical. This causes a cascade of radicals to occur. The final stage, termination, only occurs when two radical lipids interact with each other resulting in a normal functioning healthy fatty acid. Think of it as basic math, where two negatives make a positive. However, this only occurs once the radical versions of the fatty acids take up a considerable amount of the total percentage of fatty acids in that particular cellular membrane.
“In one analysis, a total of 130 volatile compounds were isolated from a piece of fried chicken alone.”5
These volatile by-products range from various aldehydes, including the infamous formaldehyde used to preserve dead bodies. Also acrolein, which is a toxin found in cigarette smoke.6 People now understand how bad smoking is for you but people still don’t fully understand the damage there doing to their bodies by consuming these types of polyunsaturated of oils.
To further support the fact that natural fats are healthy and also our bodies’ preferred fuel, lets look into a little basic biology
First, consider that the earth has been around for about 4.5 billion years. In all that time, only two types of cells have evolved: prokaryotic and eukaryotic. As humans, we are lucky to have evolved eukaryotic cells. The major difference between the two is that eukaryotic cells contain organelles. These are specialized systems designed to make the cell more efficient. One of these organelles is the mitochondria. Our mitochondria are specifically designed to metabolize fat. The mitochondria are the power plants of the cell, responsible for ATP production. The fat we eat is transported directly into the mitochondria on the back of an L-Carnitine amino acid, no pre-processing required. However, carbohydrates have to first get broken down into glucose and then in the cytosol (the soup in which all organelles are contained) has to be converted into pyruvate before it can be transported into the mitochondria. This releases reactive oxygen species in the cytosol that have to be cleaned up by peroxisomes (an organelle). However at this point the pyruvate can be converted into lactate before it even enters the mitochondria. So the part of the glucose that is converted into pyruvate is then transported into the mitochondria to be converted into ATP. Just comparing these two systems it’s clear that fat is metabolized much more efficiently than glucose. On top of this, on a per carbon basis, you get more ATP from fat metabolism than glucose. You get 8 ATP per carbon from fat and only 6 ATP per carbon from glucose. In every way, fat is a superior fuel.
I also want to touch on the idea that “fatty acids” are something special
This term had to be created to create distance from the traditional term “fat.” Whether you know it or not, every “ fat” is a fatty acid. They all have a carboxyl end (COOH acid) and a methylated carbon on the other end. A methylated carbon is simply a carbon attached to three hydrogen atoms. It is the fundamental make up of fat. Also, the term “omega” makes certain fats seem especially unique. However this isn’t true either. All fats have an “omega” end and a “alpha” end. It’s just a fancy term for saying the right or left side of the fat. The methyl end is omega and the carboxyl end is alpha, nothing else. It just gives you a frame of reference needed to properly identify characteristics of the fat.
So an omega 3 fatty acid is a normal fat that has a double bond on the third carbon from the methylated end
A better way to distinguish fats that are vitally important are to look into fats that are essential. Essential fats can’t be created by the body and there are two of them. An omega 3, called alpha-linolenic acid and an omega 6, called linoleic acid (complaint from author: I really wish these two didn’t sound so similar!). Without an adequate supply of these fats, our body will not be able to produce the proper prostaglandin levels, which are locally-produced hormones, and simply will not function properly. Something to consider is the source of these essential fatty acids. The omega 3 alpha-linolenic acid is important because our body will convert that through a series of enzymatic reactions into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are vital nutrients. And in reality, these are the omega 3 fats that take credit for the health claims made by the omega 3 name.
Unfortunately ALA which is found in seed oils and flax seeds in high amounts is only converted to the beneficial forms EPA and DHA in very small amounts, 0-9%. So you can eat flaxseeds till you’re blue in the face, but you still wont be getting adequate amounts of EPA and DHA.4
To get the adequate amounts of these fats, you have to eat animal-sourced fats. You’ll find both EPA and DHA in meats and eggs. They are especially high in sea food, salmon, and other fatty fish.
You might be worried to add animal fats into your diet after being bombarded with negative information about their content for years, but here is some information that will hopefully change your mind
Through the media, most people have been convinced that olive oil is healthy because it is predominately a monounsaturated fat. This fact is true, however, most people have been tricked into believing that beef fat, or animal fat, in general is saturated.
This isn’t true, because beef fat is 54% unsaturated, and lard is 60% unsaturated. So they should both be called unsaturated fats.
Just like olive oil. So don’t be afraid to cook in lard or beef tallow. They are perfectly natural and chemically stable fats.
References
- Enig, Mary. Know Your Fats. Pg 46. Published by Bethesda Press. 1st Edition.
- Enig, Mary. Know Your Fats. Pg 27. Published by Bethesda Press. 1st Edition.
- Enig, Mary. Know Your Fats. Pg 64. Published by Bethesda Press. 1st Edition.
- Daniel, Kaayla T.. The Whole Soy Story: The Dark Side of America’s Favorite Health Food (p. 179). National Book Network – A. Kindle Edition.
- Teicholz, Nina. The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet (p. 279). Simon & Schuster. Kindle Edition.
- Teicholz, Nina. The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet (p. 281). Simon & Schuster. Kindle Edition.