Understanding the Difference Between Good Fats & Bad Fats
Essential Fatty Acids, Good Fats, Bad Fats and Trans Fats.
Essential fatty acids are essential for good health. They are called “essential” because our bodies can not naturally produce them. We must get them from our food. These fats are most abundant in flax seed oil and fish oils. Good fats may or may not contain the essential fatty acids. But, they do contain otherwise undamaged, healthy fatty acids. Bad fats are fats which are composed of damaged fatty acids. Damaged fatty acids (which will be discussed later) are also called trans fatty acids, and they interfere with cellular functions. These damaged fatty acids mainly arise from the large scale oil and food processing practices that are currently followed in the food producing industries.
A lot of research has been done on fats in more recent years, which brings to light a strong connection between the lack of essential fatty acids in the diet, and an ensuing tendency toward the development of chronic degenerative diseases such as heart disease, stroke, and cancer. These diseases account for the majority of pathological deaths in America today.
What Are Fatty Acids?
A fatty acid is the main building block of a fat of a lipid molecule. Lipids and fats are that group of molecular substances to which the common oils and fats such as butter, olive oil, margarine, and cooking oils belong. Fatty acid is simply a long electrically neutral carbon chains with a reactive acidic head at one end. The reactive " acidic" head of the fatty acid joins to a glycerol molecule when a triglyceride is formed. These types of lipids are call triglycerides since they include three long (or longer) fatty acid chains. Besides triglycerides, lipids also include the phospholipids (made up of just two fatty acid chains) and the sterols (cholesterol, for example). Our cell membranes are composed mainly on these two types of lipids. Are cell membranes made from fat? Yes, it is true: the main constituent of a cell membrane is the phospholipid molecule.
Most of the fats we consume in our food are triglycerides. We eat them whole, but we break them down into their constituent parts – the fatty acids and the glycerol molecule. This enables us to absorb them easily. A triglyceride is much too bulky to be absorbed across the intestine wall. Free fatty acids are more easily transported across membranes, and through vessels.
Edible Oil Chemical Property: Understanding Good versus Bad Oils
The edible oil chemical property is governed by the nature of the fatty acids of which the oil is composed. To understand how particular oils affect your body you need to understand the nature of the fatty acids that make up that oil.
SATURATED FATS
In a saturated fat, the carbon chain of the fatty acid part of the molecule has filled every bonding place along this chain with a hydrogen atom. In other words, in a saturated fat all of the fatty acid carbon hydrogen holding capacity is filled (i.e. saturated). As a result, the carbon chain is long and straight. Saturated fatty acids can pack together easily since the carbon chains of saturated fatty acids are so straight and because, compared to their un-saturated counter parts, they are of a more inert nature. Saturated fatty acids are not actually harmful in the sense that a trans fatty acid is harmful (we will look at trans fats in the next part of this series) but saturated fatty acids lack many of the benefits that unsaturated, fatty acids, and in particular of the essential fatty acids.
Fats which are composed of saturated fatty acids are solid or semi-solid at room temperature because of their easy packing properties. Butter, lard and coconut oil would be examples of fats made up of primarily saturated fatty acids. These fats are not easily damaged by heat, and are good for cooking with.
UNSATURATED FATS
Fats which are composed of unsaturated fatty acids have some carbon atoms in the carbon chain which have not bonded with two hydrogen atoms. In other words their hydrogen bonding capacity is ‘unsaturated’ as they still have room to take one more hydrogen atom on. When a carbon atom is ‘unsaturated’ it bonds to its neighboring carbon (who must also by default be unsaturated as well) with the extra bond. In other words neighboring unsaturated carbon atoms in an unsaturated fatty acid chain share a double carbon to carbon atom bond. This double carbon to carbon atom bond behaves very differently from a single carbon to carbon atom bond. It is much less stable - much more inclined to involve itself in chemical reactions, and in biological systems the bond will always be configured in the ‘cis’ configuration.
This ‘cis’ configuration of the carbon to carbon bond in the unsaturated fatty acid chain results in a bend in the carbon chain. In other words unsaturated fatty acid carbon chains are kinked. They do not pack together as well as saturated fatty acids do. As a result, unsaturated fatty acids tend to remain liquid at room temperatures. On account of the chemical volatility of the double bonded carbons in the fatty acids, these oils are damaged easily by applying heat to them and by exposing them to oxygen and to light. Modern oil processing methods tend to damage these oils quite considerably since these methods rely, among other things, on high temperatures. Only unrefined cold pressed food oils are free from the danger of processing damage. The vegetable oils that you can buy in the supermarket today are simply not safe. These oils all contain trans fatty acids on account of the processing techniques that were used to extract and refine them as well as other oxidative products of fatty acid reactions.
You can really only find safe vegetable oils in health food stores today. Even with a properly extracted and un-refined oil, such as this, you still would not want to use such an oil for frying or for high temperature baking, such as with cookies. Most unsaturated fatty acids can be added to food that is no hotter than the temperature of boiling water. Flax seed oil, however, and any other oil which is high in omega three fatty acids are so delicate that you should only add them to foods after the cooking is completed.
This post is part of the series: Good Fats and Bad Fats
Fats are among the least understood of the nutritive elements. Certain fats contain essential fatty acids but the Western diet fails to provided adequate and balanced amounts of these. Bad fats are all too prevalent in the Western diet and these fats yield damaging effects upon health.