Fat is somewhat misunderstood when it comes to nutrition. A person needs fat in order for their body to function properly. It is an energy source, it helps regulate blood pressure, heart rate, blood vessel constriction and blood clotting. It also is the way that various vitamins are delivered into our blood stream.
There are two ways one needs to look at fat. First, in a high level overview of fat as a whole, then a lower level look at the various types of fat. I believe this is important, because fat, at its base level, is a means in which energy is delivered to our bodies.
The issue surrounding fats is not whether it’s good or bad, but rather how much is too much. Much like everything else in life, fat is best taken in moderation. Being rather high in calories, it’s easy to overindulge. 5 grams of fat contains 45 calories. As a point of comparison, 5 grams of either proteins and carbohydrates contains only 20 calories. Fat is a very efficient means in delivering calories. Foods high in fat are probably not the best items to eat when you wish to feel “full”.
At the lower level, fats molecules can be divided into various categories -
Each of these fats provides a specific nutritional function and have both pros and cons, some more than others.
Unsaturated Fat – An unsaturated fat is a fat or fatty acid in which there is one or more double bond in the fatty acid chain. What exactly is it missing to be “un”-saturated? That’d be hydrogen atoms, some of which are eliminated when the double bonds are formed in the chain.
There are two types of unsaturated fats:
- Monounsaturated Fat – A fat molecule is monounsaturated if it contains only one double bond. A good way to remember which fats are monosaturated is that they remain liquid at room temperature but may start to solidify in the refrigerator. Olives and olive oils, avocados, nuts and various nut oils all are good examples of monosaturated fats.
- Polyunsaturated Fat – A fat molecule is polyunsaturated if it contains more than one double bond. Polyunsaturated fats are typically liquid at room temperature and when refrigerated. Polyunsaturated fats are considered the healthiest, and include the Omega oils (Omega 3, Omega 6)
Not all unsaturated fats are considered “healthy”. The trans fats we’ve heard so much about of late is an unsaturated fat, but deserves its own subcategory in the unsaturated fats field. I’ll discuss trans fats in a later post.
Saturated Fat – Saturated fatty acids have no double bonds between the carbon atoms of the fatty acid chain. Thus, since no hydrogen atoms are “exterminated”, they are “saturated” with hydrogen. You can recognize most saturated fats as they remain solid a room temperature. Think of bacon fat, butter, vegetable shortening, etc, etc.
This is a basic overview of fats, and I’ll discuss each individual fat in its own post later on.