Introduction
We seem to have a love/hate relationship with fats. On one hand, we embrace fat-free foods and prepared foods. On the other hand, we are told fats are good for us and are essential to maintain optimum health and well-being. Both, in fact, are true.
Fats are essential for proper homeostasis -- an overall balance within the body. They are needed to transport nutrients and other compounds around the body and facilitate energy storage, vitamin and mineral absorption (particulary A, D, E, and K), hormone synthesis, cell membrane flexibility, organ protection, and body insulation. Our brain is composed primarily of fat and requires the fat found in oils to function properly. Indeed, a number of fats are referred to as Essential Fatty Acids and the term is quite literal.
On the other hand, excess, non-essential fat consumption can lead to heart disease, obesity, high blood pressure, high cholesterol, cardiovascular disease, and a variety of cancers. To counter this disturbing relationship, you must balance with those fats that have a beneficial effect on the body.
In general, calories from fat should comprise 15 to 30% of your daily total intake. So which fats do you add to your diet and which should you shun? The following descriptions and guidelines will help set you on course.
Which Witch is Which?
Saturated fats, unsaturated fats, hydrogenated fats...seems like an alphabet soup of confusion. There are key differences, however, between the different kinds of fats. You should ensure you receive some while striving to eliminate others. A fat can be friend or fiend depending on its level of saturation -- the number of hydrogen molecules latched on to a fat molecule. Here is the breakdown:
Essential Fatty Acids (EFAs)
Essential fatty acids help build nerve cells, synapse membranes, and the myelin sheath that covers most nerve fibres. They help transport and metabolize cholesterol and fats in the blood and stored fats in muscle tissue. These acids also form prostaglandins -- hormone-like substances that act as neuronal messengers in the body, facilitating proper nervous system, immune system, and cardiovascular function. In addition, EFAs transport vitamins, minerals, and other fat-soluble compounds required by your body and support proper immune system function.
EFAs come in two forms: omega-3 fatty acids (alpha-linolenic acid) and omega-6 fatty acids (linoleic acid). These fatty acids are not synthesized internally and must be obtained from your diet.
Omega-3 fatty acids are converted into eicosapentainoic acid (EPA) and docosahexaenoic acid (DHA), then into prostaglandins. Fish oil is high in omega-3 fatty acids and perilla seed (Chinese basil) and flaxseed/linseed oil are also both excellent sources. Other oils include borage, corn, evening primrose, hemp, pumpkin seed, safflower, and soybean oil. Eggs are yet another source of omega-3 fatty acids.
Omega-6 fatty acids are converted into gamma linolenic acid (GLA), which converts into di-homo gamma linolenic acid (DLA), then into prostaglandins. Beans, walnuts, borage oil, evening primrose oil, and hemp seed oil are high in omega-6 fatty acids.
The ideal ratio of omega-6 to omega-3 fatty acids is 2:1. Most people obtain too many omega-6 compared to omega-3. You can balance out by taking flaxseed oil.
Be sure the oils are unrefined and expeller-pressed/cold-pressed. Also, do not cook with EFA oils. Heat denatures these oils and they lose their nutritional value.
Be sure to keep EFA oils (and unrefined/unhydrogenated oils in general) refrigerated as they will go rancid if not kept cool.
For more information, see Food Supplements -- Essential Fatty Acids.
Monounsaturated Fats
Monounsaturated fats are, overall, all right for you. Found in almonds, peanuts (not a recommended source), and sesame seeds, canola and olive oils, and avocados, these fats can decrease cholesterol levels. Such fats also harden at cold temperatures or turn cloudy and solidify once refrigerated.
Polyunsaturated Fats
Polyunsaturated fats, are overall, good for you -- as long as you do not overdo it. Found in corn, safflower, sunflower, and soybean oils, walnuts, pecans, and walnuts, these fats can benefit the heart and also reduce cholesterol levels. Their benefits are well known and well documented. One downside is that such fats tend to go rancid more easily than other oils. Be sure to keep them refrigerated.
Saturated Fats
Saturated fats are, overall, not desirable. Found in animal products including cheese, eggs, and dairy in general, these fats promote excess cholesterol production in the body. Butter is a saturated fat. It remains solid at room temperature. Other saturated fats include coconut and palm oils, the staple of many processed foods and sweet goods. Reduce your intake of these fats and avoid processed foods containing saturates all together. Your heart will thank you.
Trans-Fatty Acids / Hydrogenated Fats
These fats are evil. Widely available and widely used, these fats should be avoided at all times. Found in low priced commercial oils and countless processed foods ranging from cookies to corn chips and salad dressings, they are cheapest to make and employ and have an extremely long shelf life (as all natural components have been denatured due to high levels of heat).
Heat turns polyunsaturated fats to trans-fatty acids by adding an extra hydrogen atom to the fat molecule chain. This "mutated" fat is not natural and cannot be absorbed or digested by the body. As a result, such fats end up floating through the body and are eventually deposited on arteries and veins, leading to a variety of circulation-related ailments. Low Density Lipoprotein (LDL) cholesterol levels increase, contributing to cholesterol-related problems.
Fat Breakdowns
This table shows the breakdown of various fats in a variety of foods and oils.
| Food | Saturated (%) | Monounsaturated (%) | Alpha-Linolenic (Omega-3) (%) | Linoleic (Omega-6) (%) |
Butter | 66 | 30 | 2 | 2 |
Canola | 7 | 61 | 11 | 21 |
Coconut | 92 | 6 | nil | 2 |
Corn | 14 | 25 | 1 | 60 |
Flax | 9 | 19 | 58 | 14 |
Hemp | 9 | 13 | 20 | 58 |
Lard | 41 | 47 | 1 | 1 |
Margarine | 18 | 48 | 5 | 29 |
Olive | 14 | 77 | 1 | 8 |
Peanut | 18 | 48 | nil | 34 |
Safflower | 9 | 13 | trace | 78 |
Soybean | 15 | 24 | 7 | 54 |
Sunflower | 11 | 20 | nil | 69 |
In Closing ...
Fats are an essential part of a healthy diet. Deficiencies can cause numerous ailments ranging from high cholesterol to learning complications.
Be sure to read labels and know what kinds of fats you are adding to your diet. Stick to unrefined oils and use in moderation.
