About Omega 3
Essential Building Blocks!
Omega-3 fatty acids are an essential building block for the human body and brain. They have been linked with cardiovascular and mental health as well as the prevention of inflammation and cancer. But what are they, and how do they work?
So, we have essential vitamins, minerals, amino acids… and fatty acids! These essential nutrients are required by our bodies, yet our bodies cannot synthesize them. Typically, these essential nutrients are necessary for the body to synthesize a multitude of other crucial molecules. In the case of fatty acids, there are two that are considered dietary essentials: α-linolenic acid (ALA) and linoleic acid (AL). The latter, AL, is a precursory omega-6 molecule from which our bodies can synthesize the other necessary omega-6 molecules. The former, ALA, is the omega-3 precursor molecule.
Currently, omega-3 and omega-6 fatty acids are both considered required nutrients. Unfortunately, it’s often difficult to talk about (or study) one without the other. Omega-3 and omega-6 fatty acids tend to be antagonistic to each other. For example, some eicosanoids derived from omega-6 fatty acids are inflammatory, while those eicosanoids derived from omega-3 fatty acids act as anti-inflammatory agents. Part of the anti-inflammatory effect of omega-3-derived eicosanoids comes from them replacing the omega-6-derived eicosanoids! However, we’ve known since the 1930s that a diet without either of these fatty acids has serious harmful effects.
Technically, α-linolenic acid (ALA) is the only “essential” omega-3. However, research on the health benefits of omega-3s tends to focus on docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Supplementation with (or deficiency in) these two omega-3 fatty acids has been found to have effects on rheumatoid arthritis, triglyceride levels, mental acuity, visual acuity, and more. But, while considered necessary, neither DHA or EPA are classified as “essential.”
The human body is suppose to be able to convert ALA to EPA and DHA, making DHA and EPA non-essential. ALA can be metabolized down to EPA, and it is actually EPA that is metabolized to DHA (making it impossible to study EPA supplementation without DHA!). However, the efficiency of this process is not ideal. Young men, for example, have been found to not convert ALA to DHA and EPA in any measurable amount. For this reason, Omega-3 IQ focuses on making sure you get enough EPA and DHA, rather than just ALA!
Fats as Building Blocks
Maybe you think fat is only good at increasing the numbers on the scale. Maybe you recognize fats as an important source of energy. But did you know fats and fatty acids are crucial to life as we know it? Fats are a simple lipid comprised of glycerol and three fatty acids. When we are talking about whether a fat is saturated or unsaturated, we’re actually talking about the fatty acids!
Fats are synthesized and then broken down into those four components over and over again within our bodies. These components are major sources of cellular energy, but they are crucial as more than just cellular fuel.
Fatty Acids in Cell Membranes
When one of the fatty acids of the fat is replaced by a phosphate molecule, a phospholipid is created. Phospholipids are crucial to all life as we know it; without phospholipids, we would have no cell membranes… or cells! A bilayer of phospholipids forms the cell membrane, with proteins embedded in the cell membrane to allow the passage of molecules into and out of the cell.
There are, however, a lot of different phospholipids – all based on what kind of fatty acids they use. These different phospholipids affect the functioning of the cell membrane. You may have heard that, as a general rule, solid fats like lard are mostly saturated while liquid fats like canola and olive oil are mostly unsaturated. This principle also applies to cell membranes; phospholipids formed with unsaturated fatty acids tend to be more “fluid.”
There are many additional effects of particular phospholipids within the cell membrane. Some, we know; many are yet to be discovered.
We do know that DHA is incorporated in high concentrations into the cell membranes of neurons, and this is assumed to cause many of the positive mental effects associated with DHA supplementation. Moreover, we have found that the omega-6 docosapentaenoate acid competes with DHA for presence within neurons. Studies have increasingly found that the ratio of omega-3 fatty acids to omega-6 fatty acids in the diet was just as important as getting enough of either (with a higher amount of omega-3s being preferred for good health). This is one possible reason for that effect!
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