Final answer:
An essential fatty acid must be obtained from the diet because the body cannot produce it on its own. Omega-3 and omega-6 fatty acids are the only known essential fatty acids that humans need to ingest, and they are vital for normal brain function and growth.
Step-by-step explanation:
Essential Fatty Acids
An essential fatty acid is a type of fatty acid that the body cannot synthesize on its own and therefore must be obtained from the diet. Of the many fatty acids, only two are classified as essential for humans: omega-3 and omega-6 fatty acids. These fatty acids are crucial for normal growth and development and play a vital role in brain function, as well as normal growth and development.
Good sources of omega-3 fatty acids include fatty fish like salmon, walnuts, and flax seeds, which are not as prevalent in the standard diet. Omega-6 fatty acids, which are also essential, can be easily obtained from commonly used cooking oils found in processed foods. As essential nutrients, these fatty acids must be consumed in sufficient amounts to support the body's physiological functions, including the maintenance of cell membranes and the production of signaling molecules.