Michael Nicolos
3/2/14
Health
What is Fat?
Fats have acquired a very negative connotation over time. Through our misunderstandings, we have incorrectly labeled “Fat” as an unwanted part of our anatomy. While it is true that excess fat can be harmful and sometimes lead to fatal consequences, we simply could not survive without it. In biological terms, fats provide energy storage, protection as well as other functions necessary to sustain life. The most common type of fat molecule we encounter on a daily basis is called Triglyceride. Triglyceride is found in products such as butter or olive oil. The Triglyceride molecule has a head (composed of Glycerol) and three fatty acid tails (composed of Hydrocarbons). It is the breaking down of these tails by enzymes called Lipase's that provides energy so that our bodies can store it and use it for a later time. The fatty acid tails attached to the Glycerol head are made up of a chain of Carbon and Hydrogen atoms. These atoms are arrange in different structures depending on whether or not double bonds are present between the Carbon atoms in the molecule. For example, a chain of Hydrocarbons with no double bonds presents itself in a linear formation and is said to be Saturated. A chain of Hydrocarbons with only one double bond presents itself with a kink at a point in the chain resulting in an obtuse formation and is called Monounsaturated. Furthermore, a chain with multiple double bonds results in multiple kinks throughout its molecular structure and is said to be Polyunsaturated. The terms Saturated, Monounsaturated and Polyunsaturated refer to the saturation of Hydrogen atoms within the fat molecule. A linear, Saturated molecule of Triglyceride means that the molecule has the most amount of Hydrogen atoms it could possibly have without gaining another Carbon atom. Carbon atoms have four valence electrons, meaning that they naturally want to make four bonds to become stable. In a chain of Saturated Hydrocarbons, with the exception of the first and last Carbon atoms, each Carbon atom is attached to two Hydrogens and two Carbons to form a chain. Therefore, every bond that can be made to a Hydrogen atom is made; hence Saturated (with Hydrogen atoms!) In a Monounsaturated fat molecule, one of the Carbon atoms at some point in the chain is double bonded with another Carbon atom instead of a single bond with a Hydrogen atom; hence Mono-Unsaturated. This double bond changes the trajectory of the rest of the chain giving it a kink. Similarly, a Polyunsaturated fat Molecule has multiple double bonds between Carbon atoms, giving it multiple kinks and even less Hydrogen atoms. Due to the linear nature of the Saturated fat molecule, Saturated Triglycerides are able to stack upon each other in a very dense fashion causing them to be solid at room temperature. This is what we know as butter. Conversely, due to the kink-full nature of Unsaturated fats (Mono and Poly), these fats are unable to make themselves as dense and are liquid at room temperature known as oils (corn, olive...etc). A fourth state of fat that has been introduced to the world due to human ingenuity is called Trans Fat. Man is able to take Unsaturated fats and shoot loose Hydrogen atoms through them. At high temperatures, this causes the double bonds between Carbons to break and are replaced with single bonds to Hydrogen atoms, essentially turning the oil into Saturated fat. This process is called Hydrogenation. While cooking foods in Hydrogenated oils is cheaper, gives the product a longer shelf life and tastes better than alternatives, it is much more harmful to humans than any other type of fat. Our bodies are unable to use this new type of fat as energy. Consequently, we store it as we would any normal type of fat molecule, but are unable to use it when we want to. This dilemma results in excess body fat, higher levels of LDL or “Bad Cholesterol” and lower levels of HDL or “Good Cholesterol.”