Fats are one of the three major macronutrients. Fats are organic molecules composed of carbon and hydrogen that are linked together in long chains known as hydrocarbons. Different fats are formed based on the arrangement of these hydrocarbon chains and their interactions with one another.
A fatty acid is the simplest unit of fat. Fatty acids are hydrocarbon chains with variable hydrogen and carbon configurations. All fatty acids have a methyl group (CH3) on one end and a carboxylic acid group (COOH) on the other.
Saturated fatty acids and unsaturated fatty acids can be formed based on the level of saturation (the number of hydrogens connected with each carbon along the hydrocarbon chain).
Unsaturated fatty acids can also be divided into monounsaturated (just one carbon is unsaturated) and polyunsaturated fatty acids (more than one carbon is unsaturated).
It’s worth noting that the commonly discussed omega-3 and omega-6 fats are actually polyunsaturated fatty acids. The distinction between these two omega fats is that different carbons along the fatty acid chain are unsaturated.
Fatty acids can be combined to generate triglycerides. A triglyceride is formed when three fatty acids combine with one molecule of glycerol. Triglycerides are the most common kind of fat found in the diet. Furthermore, they are the most common type of fat storage found in the body.
Fat in diet
Dietary fat is essential as an energy source (it is the most energy-dense macronutrient), in the production and balancing of hormones, in the construction of cell membranes, in the formation of our brains and nervous systems, and in the transfer of fat-soluble vitamins A, D, E, and K.
In addition, dietary fat contains two important fatty acids that the body cannot produce: linoleic acid (an omega-6 fatty acid) and linolenic acid (an omega-3 fatty acid).
As noted previously, the majority of dietary fat is in the form of triglycerides. Surprisingly, naturally occurring triglycerides often contain both saturated and unsaturated fats.
Remember that triglycerides are composed of three different fatty acids attached to one glycerol backbone. Therefore, different fatty acids can combine to form one of the countless permutations of possible triglycerides. As a result, most dietary fat sources include a mix of saturated, polyunsaturated, and monounsaturated fatty acids.
For instance, most people think that eggs and red meat are high in saturated fat, but eggs have more monounsaturated fatty acids than saturated fatty acids. In fact, 39% of the fat in an egg is saturated, 43% is monounsaturated, and 18% is polyunsaturated. Beef also has 55% saturated fat, 40% monounsaturated fat, and 4% polyunsaturated fat.
Even though most triglycerides are made up of different types of fatty acids, the main type of fatty acid is what gives the food its chemical properties. For example, foods that are higher in saturated fatty acids tend to be solid at room temperature, while foods that are higher in unsaturated fatty acids tend to be softer (or liquid) at room temperature.
Lauric, myristic, and palmitic acids
The balance of fatty acids consumed contributes to general health. A diet heavy in saturated fatty acids (including lauric, myristic, and palmitic acids—three forms of saturated fat) can raise cholesterol levels when consumed in excess and out of balance with a variety of unsaturated fats.
Indeed, these forms of saturated fat are associated with an increased risk of cardiovascular disease (mainly due to their cholesterol-raising effects and the unfavourable shifts they bring about in the overall cholesterol profile).
Moreover, an excess of these saturated fats (an imbalance in the consumption of unsaturated fats) has been linked to Alzheimer’s disease, poor blood viscosity, breast cancer, renal illness, diabetes, multiple sclerosis, stroke, and prostate cancer. Beef, coconut oil, palm kernel oil, butter, cheese, milk, and palm oil all contain lauric, myristic, and palmitic acids.
Nevertheless, these correlations do not apply to all saturated fats. Stearic acid, for example (another saturated fat found in cocoa butter and beef), may actually reduce LDL cholesterol levels. As a result, saturated fat should not be widely recognised as harmful.
Furthermore, it is crucial to remember that the problems linked with saturated fat consumption are not always independent. Indeed, they may appear only when other bad dietary choices are present. Indeed, when saturated fat consumption is excessive and two additional dietary variables are present (a diet heavy in sugar and processed carbohydrates, and a saturated fat consumption that is out of balance with unsaturated fat intake), extra body fat, unfavourable blood lipid alterations, and higher CV disease risk all appear to occur.
As a result, instructions to avoid saturated fat are erroneous. When refined carbohydrate intake is limited and a sufficient quantity of unsaturated fat is present, saturated fat appears to be fine. However, one should not mix a low-saturated-fat diet with a high-saturated-fat, sugar, and refined-carbohydrate diet.
Healthy fats
Due to their distinct qualities, unsaturated fats are frequently referred to as “healthy fats” in common parlance. In this context, polyunsaturated fats, notably omega-3 and omega-6 fatty acids, stand out. These fats are termed chemically depending on the location of their double bonds.
Omega fats and monounsaturated fats (all unsaturated fats) are widely supported these days due to their favourable effects on blood triglycerides and cholesterols, blood vessel health, inflammation, and metabolism. People are getting too much saturated fat relative to unsaturated fat in the current diet, because of the high predominance of animal foods and the low prevalence of plant foods. As a result, their health suffers.
Balance is also vital when it comes to unsaturated fats. Humans really developed on diets rich in omega-3 and omega-6 fatty acids from marine life and inland plants. As a result, the omega-6/omega-3 ratio was around 1:1. This ratio has moved to a severely disproportionate 16:1 in the modern diet. This is utterly out of whack in terms of cellular health and integrity.
This imbalance is caused by a high diet of omega-6 fatty acids from corn oil, safflower oil, and feedlot meat (animals that eat high amounts of corn). As a result, establishing a healthy omega-6 to omega-3 fat ratio is dependent on two factors. One must intentionally consume less omega-6 fatty acid-rich vegetable oils and more omega-3 fatty acid-rich meals.
Of course, omega-6 fats should not be eliminated from the diet. LA (linoleic acid), GLA (gamma-linolenic acid), and AA (arachidonic acid) are the most significant omega-6 fats. These omega-6 fats are responsible for the release of eicosanoids, which promote blood vessel constriction, inflammation, blood clotting, pain, and airway constriction, among other things. While each of these may appear to be harmful, each process is essential to general health.
When there are too many omega-6 fats in the diet and these mechanisms take over, there is a problem. People should try to get an adequate quantity of omega-3 and omega-6 fats in their diets.
Omega-3 fats (ALA, EPA, DHA)
Alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) are the three most crucial omega-3 fats. The most beneficial omega-3 fats, EPA and DHA, are found in fish oils and algae (the original omega-3 sources for fish), whereas ALA is abundant in flax oil and walnuts.
Omega-3 fats are significant because they are incorporated into cell membranes, where they contribute to maintaining cellular “fluidity.” The fluidity of the lipid membranes that surround our cells has several potential benefits.
For instance, neurochemical signals like serotonin are better transferred when the membranes of brain cells are somewhat fluid. Insulin sensitivity also improves when the membranes of muscle cells are more fluid. These necessary fats are also important for cardiovascular function, nervous system function, and immune health.
In addition, studies have linked inadequate DHA consumption (and blood levels) to memory loss, difficulty concentrating, Alzheimer’s disease, and other emotional distress.
Apart from these relationships, omega-3 fatty acids aid in the production of some eicosanoids. Eicosanoids derived from omega-3 fats have been shown to promote blood vessel dilatation, anti-inflammatory effects, anti-coagulant effects, pain relief, airway dilation, and other benefits. As you can see, omega-3 fats have the opposite effect. So it’s the essential balance of omega-3 and omega-6 fats that keeps us healthy.
Trans Fat
Trans fats are another distinct category of fats that are frequently mentioned in the media. The term “trans” refers to the chemical arrangement of the double bond in unsaturated fats. Wherever there is a carbon-carbon double bond, there is the possibility of a “cis” or “trans” configuration. Almost all naturally occurring unsaturated fatty acids are in the cis form. While some fatty acids occur naturally in the trans form, the vast majority of trans fats in the diet are the result of industrial fat processing.
Trans fats are generated by bubbling hydrogen ions through an unsaturated fat (soft or liquid at room temperature). It is “hydrogenated” during this process, causing it to harden at room temperature. Regrettably, instead of preserving a cis structure, the fatty acid adopts a trans form as a result of this action.
In order to improve the flavour and shelf life of oils, companies “hydrogenate” fats to produce “trans” fats.
Yet, because trans fats do not kink or fold onto themselves like cis fats, they pack very firmly into our bodies’ cell membranes. Unfortunately, clinical and epidemiological research indicates that this increases the risk of coronary heart disease, cancer, and other chronic diseases. For example, elaidic acid, a trans-isomer of oleic acid, raises cholesterol and may lead to heart disease.
Trans fats, on the other hand, not only elevate the bad type of cholesterol but also lower the healthy form—a double whammy. Excess trans fat consumption has been linked to:
- An increased chance of Alzheimer’s disease
- An increased risk of lymphoma
- Suppression of bile acid excretion
- Increased cholesterol synthesis in the liver
- Competing for essential fat update
- The exaggeration of essential fatty acid deficiency
Even a single meal heavy in “bad fat” can affect blood vessel function and elasticity. This can potentially lead to heart problems.
It’s important to remember that not all trans fat configurations are bad for you. Certain trans fats are found in nature. CLA is an example of a trans fat that is really good for your health. CLA is produced in the rumens of cows and sheep.
Finally, the ideal strategy for controlling trans fats is to eat a diet rich in natural, unprocessed, whole foods. It is nearly impossible to accumulate high levels of trans fat in such a situation.
The Bottom Line
To summarise, dietary fat is essential for good health and function. Importantly, fat balance is essential for promoting health. The optimal dietary fat approach appears to be a combination of saturated, monounsaturated, and polyunsaturated fats (with a balance of omega-3 and omega-6 fats). Also, like with carbohydrate consumption, dietary fat and dietary carbs should be inversely proportionate. Carbohydrate intake should be reduced when fat intake is high. Carbohydrate intake should be increased if fat intake is low.