It’s time I shared the skinny on fats with everyone. Which fats contribute to improved health, which fats promote a decline in health and why. To this day we are still inundated with conflicting information from seemingly renowned sources.
All fats have a glycerol head and a fatty acid chain of varying length or carbon atoms, how fat is categorized depends on whether there are open bonds in the fatty acid chain.
Saturated fat has a carbon chain with no open molecular bonds. Saturated fats are stable because a hydrogen atom occupies each carbon molecule, meaning that all possible open bonds are closed or “saturated”. This means that saturated fat is stable under heat and not prone to oxidation. Various environmental extremes including heat, light, moisture, and air can oxidize molecules. Below is an example of fully saturated fat, notice how there are no open bonds and therefore no place for oxygen to damage the molecule.
Short Chain Fatty Acids
There are various lengths of carbon chains with all fats, each fat category can have a short, medium and long chain fatty acid. Short chain fatty acids are usually found in full-fat dairy products and are produced in the large intestine from the fiber and starch we eat. The body uses ubiquitously uses Butyric Acid (a short chain fatty acid) throughout the body, butyric acid primarily supports cells in the small and large intestine, and is also the favored source of fuel for the cells lining the interior of the large intestine (17, 24).
Research indicates numerous benefits from the consumption of short chain fatty acids, including relief from gastrointestinal distress caused by leaky gut, irritable bowel syndrome, Chrohn’s Disease and other digestive disorders (24, 3). Short chain fatty acids can also substantially lower circulating triglycerides and production of very low-density lipoproteins (VLDL), an easily oxidized lipoprotein implicated in the development of cardiovascular disorders.
Short chain fatty acids also promote weight loss by sensitizing the body to insulin signaling and favorably altering the gut biome (6, 8). Short chain fatty acids can amplify the benefits of probiotics, help crowd out pathogenic bacteria and favorably change the diversity of the microbiome.
Inflammation modulation is another benefit of short chain fatty acids.
Compounds like butyric acids prevent the recruitment, production, and adhesion of proinflammatory cytokines (20). Cytokines are junk released by our immune system in the process of healing injuries and killing pathogens. In the process of doing its job, the “junk” produced from the immune system not only kills things but stimulates inflammation to signal the recruitment of other immune cells. You experience this recruitment process as “pain”. Often the immune system can become overactive, compounds like short chain fatty acids keep this process from going off the rails.
Medium Chain Fatty Acids (MCT)
This saturated fat is the media darling at the moment and is central to most keto protocols. A medium chain triglyceride (MCT) can have a fatty acid chain of 6–12 carbons (6-Carpoic Acid, 8-Caprylic Acid, 10-Carpic Acid & 12-Lauric Acid). The most abundant sources of MCTs include coconut and palm oil. MCTs are liquid at room temperature, doesn’t require bile acid, lipases, and carnitine for absorption into circulation, and can be converted to ketones easily by the liver (18).
Researchers have associated MCT oil with improvements in brain health through the production of ketones and mitochondrial biogenesis (makes new mitochondria) (2). Ketones are an abundant energy source with the ability to cross the blood-brain barrier. These MCTs also support gut health by balancing pathogenic bacteria and improving the diversity of healthy bacteria throughout the gut.
Weight loss benefits of MCT Oil
The most sought-after benefit of MCT oil is weight loss. MCTs accomplish this by activating the mechanisms required for burning fat (ketosis), lowering circulating triglycerides, suppressing ghrelin production and increasing the body’s sensitivity to leptin (21, 19, 4). When triglycerides are lowered all variety of hormones can reach their receptor sites more easily (e.g. serotonin and dopamine), which is why people also “feel good” when consuming more MCTs and supporting ketosis (and short chain fatty acids).
Long Chain Triglycerides
Long chain saturated fats have carbon chains ranging from 13-21+, are solid at room temperature and have a high melting point. Any oil you see at the store that is solid at room temperature and isn’t hydrogenated, contains some amount of long chain triglycerides. When you read articles about artery-clogging saturated fat, this is the fat they are referring to. It’s not necessarily evil, but it does tax the body a little more than the other saturated fats.
To digest and breakdown long chain saturated fats the liver must produce bile, cholesterol, and lecithin are released to transport and emulsify the fat. Additionally, the pancreas releases lipase to further breakdown fat. Carnitine is also essential to the transport of long chain fatty acids into mitochondria for energy production. There is even more to this process, so you can see how digesting long chain saturated fats taxes multiple systems and processes.
Secretion of bile is necessary for the absorption of fat-soluble vitamins A, D, E, & K. Long chain fatty acids are necessary to stimulate the release of bile and cholecystokinin (which further stimulates bile release), and are essential for absorption of nutrients. Without the presence of long chain fatty acids, bile doesn’t get released and causes problems for the gallbladder and liver.
Cholesterol levels will increase with the consumption of long chain fatty acids. Usually both high density lipoproteins (HDL) and low density lipoproteins (LDL) will increase, although VLDL often doesn’t (hence higher total cholesterol and lower triglycerides). The more we know about how cholesterol is oxidized and used throughout the body, the more we realize that we should focus on oxidized, small dense cholesterol. The only individuals that need to worry about long chain fatty acids are those with a rare genetic disorder that prevents them from metabolizing these fats.
Cholesterol and hormones
Your body requires cholesterol for the production of hormones, maintaining cellular membranes, acting as a secondary immune system, bile creation, and tissue repair. We often find that high cholesterol and triglycerides tightly correlate with numerous inflammatory markers. Therefore, anything that causes inflammation in the body will likely cause an increase in cholesterol, which includes aging, eating simple carbs, rancid fats, and trans fats. This means that cholesterol is not the bad guy, it is the helper and artificially lowering it (in most circumstances) is like trying to put out a fire by shooting the fire department.
Monounsaturated fats are the darling of the Mediterranean diet and like saturated fats, can vary in length. There really is no nutritional camp against monounsaturated fats. These fats can be found in olive oil, palm oil, avocados, avocado oil, AND animal fat. Yup, animal fat is nearly 1:1 split between saturated fat and monounsaturated fat.
The “mono” in monounsaturated fat defines this fatty acid. Monounsaturated fat has a single open carbon bond, which makes it “slightly” less stable than saturated fat. Oleic acid is by far the most prominent form of monounsaturated fat.
Monounsaturated fat has a host of benefits. It has been found to promote a more favorable cardiovascular risk factor profile including increased HDL and lower LDL, lower blood pressure and improved insulin sensitivity (16, 12, 1, 23).
Researchers have also found that oleic acid specifically stimulates the release of diamine oxidase an enzyme that specifically breaks down histamine in extracellular spaces especially in the small intestine, colon, placenta, and kidney (14, 11). Diamine oxidase is stored in cellular plasma membranes and released into extracellular circulation when stimulated, where it scavenges free histamine. It also regulates the body’s response to food and environmental contaminants that either introduce histamine (breathing and digestion) or stimulate its release (citrus, cured meats, and fermented food).
Any fat with more than 2 open bonds is considered polyunsaturated. Vegetable oil, canola oil, corn oil, peanut oil, and fish oil are all high in polyunsaturated fat. The only one you should consider healthy would be the fish oil. Polyunsaturated fats are not terrible unless they are oxidized and these fats are they easy to oxidize. You will also see polyunsaturated fat referred to as omega-3, omega-6, omega-7,8,9, etc., depending on the number of open bonds.
There is an entire enzymatic pathway through which your body can convert polyunsaturated fat into proinflammatory arachidonic acid (which is good in small amounts). The major benefit of omega-3’s is that it will occupy the same enzymatic pathway used by omega-6 fatty acids, which helps the body modulate inflammation (22, 15).
Otherwise, the open bonds that define all polyunsaturated fat make them prone to oxidation and once the fat is oxidized or turned rancid, the fat causes lipid oxidation throughout the body. Damaged polyunsaturated fats generate cyclic fatty acid monomers which promote systemic low levels of inflammation, increased blood pressure, increased triglycerides, increased oxidation of VLDL, increased blood pressure, joint pain and vascular damage (13).
What about Omega-3s?
Even the healthy omega-3 can become the enemy of health once it is oxidized. Therefore, it is important to take a quality fish oil, not overcook your fish, store vegetable oil in a dark, airtight container and store those containers in the fridge. This oxidation is why many people hate fish because most restaurants overcook fish and it oxidizes the fats, giving the fish a bitter, dry taste.
Grass-fed beef vs CAFO beef
The oxidation of polyunsaturated fat is also why some doctors claim saturated fat is unhealthy. One thing to know is that all fat contains every form of fat described above, whatever fat is in the highest ratio is what the fat is categorized as. Animal fat is considered saturated, because it has a slightly higher amount of saturated fat than monounsaturated fat. The ratio of fat in an animal will vary depending on how it was raised. Fat from animals raised in concentrated animal feed operations are fed a diet similar to the standard American diet, have an excess of pro-inflammatory polyunsaturated fat (omega-6) and in some cases, could be categorized as polyunsaturated (the image is an example, not a precise representation) (7).
Don’t overcook your meat!
When you overcook meat from ruminants like a cow, the fat in the beef oxidizes just like the fat in fish. A grass raised and finished cow with a lower amount of polyunsaturated fat will have less oxidized fat and other heat damaged carcinogens than meat from a cow raised in a CAFO with an exceedingly high amount of polyunsaturated fat. I would bet money that the reason researchers believe long chain saturated fats are harmful is because of the polyunsaturated fat that is oxidized when cooking animal meats, because virgin coconut oil (also high in long chain fatty acids) does not have this effect.
Best practice: Eat PROPERLY cooked fish every now and again, and avoid all other polyunsaturated fat.
Hydrogenated Fat and Trans Fat
Now this is the fat we have all grown to hate. Hydrogenation occurs when the molecular shape of liquid short-medium chain fats and unsaturated fats are altered to be solid at room temperature. They originally did hydrogenation to replace evil butter and lard with “healthy” margarine and vegetable shortening. We now know this was a huge mistake.
The hydrogenation process produces an abundant amount of trans fats, which also occur naturally in animal fat to a small degree. Changing the shape of vegetable oil so its stable at room temperature seemed so innocent and yet caused so many problems. Hydrogenated fat and trans fat increase LDL/decrease HDL (in a dose-dependent relationship), damage cellular membranes, interfere with internal phospholipid production (EPA & DHA), promote inflammation, decrease birth weight (crosses the placenta), and lowers insulin sensitivity (10, 9, 5)
Just eat real food! Focus on real sources of saturated and monounsaturated fats, seek pasture-raised animal products, eat fish, fibrous vegetables and low sugar fruits, also don’t overcook your fish and beef.
Food isn’t something you should worry about, let’s work together and take the anxiety out of eating.
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