F A T S :
When the word fat is used, it is actually referring to a class of compounds called lipids. The lipids include triglycerides (fats, and oils), phospholipids and sterols. Triglycerides are the predominant fats in both food, and the body, but all play an important role in the body.
While it is beneficial to consume a low fat diet, don’t falsely think you should consume very little or no fat. Fats are an important nutrient, and should be supplied in the diet, however in the appropriate quantity.
There are several functions of fats in the diet. Fat is a concentrated source of energy, providing nine Kcal/gm. As a source of energy, fat is crucial to prevent protein from being used as a fuel.
Fats are also important for the high satiety value. They delay the rapid development of hunger and keep you feeling full a little longer. If you have ever eaten a mostly carbohydrate food, you know you feel full for about an hour only to be hungry again. By having a little fat with meals you are satisfied longer. Fat also contributes to the palatability, flavor, and texture of foods.
The fats that are consumed in the diet can be found in several different forms. Dietary fats and oils contain a mixture of saturated, monounsaturated, and polyunsaturated fatty acids. The type of fatty acid in abundance determines if the mixture is solid or liquid. Once again, without going to in depth with chemistry, the chemical composition of a fatty acid contains chains of carbon atoms to which hydrogen atoms are attached. These attach to a glycerol structure and are what forms triglycerides. If the
Carbon atoms are filled with hydrogen atoms this is classified as “saturated”. If the carbon atoms are not completely filled with hydrogen atoms, they are “unsaturated”
Saturated Fatty Acids are the type of fats that are usually linked with many health concerns such as coronary heart disease. Saturated fats can increase blood cholesterol levels, and also be very easily stored as body fat because your body really doesn’t need them. The characteristics of dietary fats that are abundant with saturated fatty acids are solid at room temperature. This includes the fats found in animal products such as beef, poultry, fish, lard and butter. They are also found in some plant sources such as cocoa butter, coconut oil and palm oil. You may be thinking you don’t eat these sources, however look at some of the first ingredients in cake, cookies, pies, etc. you will realize you do. The saturated fats are the type of fats that should be limited in your diet.
Unsaturated Fatty Acids are known as monounsaturated and polyunsaturated. These are usually liquid at room temperature, and are the fats that come from certain plant sources. Corn, Safflower, and Sunflower oils, contain higher levels of polyunsaturated fatty acids. In the body, polyunsaturated fats have been shown to lower blood cholesterol levels when substituted for saturated fatty acids. Olive oil and canola oils contain higher levels of monounsaturated fatty acids. Oleic acid, the predominate monounsaturated fatty acid has also been shown to reduce lower total blood cholesterol and LDL-cholesterol when substituted for fatty acids.
A question that I am often asked is “Is it better to use olive oil, butter, or margarine”. My answer is that if it is used in moderation, you may use whichever you like, however if you use it often, and in substantial amounts, you may be better off using the olive oil (or canola) as part of your diet. It is important that I define what is considered moderation here. Do you know the pat sizes of butter that you get in a restaurant? If you have one or two of that size amount of butter or margarine per day, that is moderation
Essential Fatty Acids are polyunsaturated fats that your body needs to maintain optimal health, healthy skin, produce hormone like substances, and for normal growth, but cannot make them. We need to get them from the foods we eat. These essential fatty acids are called Linoleic and Linolenic Acids.
The other polyunsaturated fatty acids, which are also important, are known as Omega 3 fatty acids. Research suggests that they may help prevent blood clots that lead to heart attack or stroke. The Omega 3 fatty acids can be found in cold-water fish such as mackerel, albacore tuna, and salmon, sardines, and lake trout.
I have recently reviewed two older articles about fish oil supplements that I found interesting, and was unaware of the claims. The first, which was in a November 1996 Pufa News issue, states “Fish Oil Supplements Used Successfully In The Treatment Of Schizophrenia”. This article is based on a six-week study done by Jan Mellor and colleagues at the Northern General Hospital, Sheffield, UK on 20 psychotic patients, all suffering from chronic schizophrenia and receiving neuroleptic medication that was not adjusted or discontinued during the study. The results of the study indicated a reduction in the severity of their symptoms, particularly tardive dyskenisia (lip smacking), interest and motivation. However these conclusions are based on a single study that only involved 20 people for a short time. In my opinion, there is not enough evidence to support the claim.
The second study in March 1998 Pufa News issue states “Fish Oil Reduces Body Fat Mass”. This study by Covet C. Delarve, J. Ritz P. et al at Bretonneu Hospital in France, was a short three week study done on a group of six healthy volunteers (five men and one woman) They were given tests with two types of diet. First was a conventional French diet with no restriction on quantity, consisting of 52% carbohydrates, 15 % protein, and 32 % fat. The second, was the same diet, except 6 grams of fat was replaced with 6 grams of fish oil each day. The results indicated that while eating the fish oil, subjects showed a 0.88 kg reduction in body fat, as opposed to .30kg in the control diet. However, there was no change in body weight. In conclusion and my opinion, the test was too small and too short in duration to draw any concrete results. There are however many more recent studies that indicate these same results of omega 3 fish oil supplementation decreasing body fat.
Glycerol is backbone structure and important component of triglycerides and of phospholipids. When the body uses stored fat as a source of energy, glycerol and fatty acids are released into the bloodstream. The glycerol component can be converted to glucose by the liver and provide energy for cellular metabolism.
Glycerol can also be seperated as an individual molecule, and is used in many healthcare produts such as soap, cosmetics products, creams and foods. One unique property of glycerol is that it absorbs water. More recently, Glycerol has been used in most of the high protein bars on the market. Why you ask? Because although glycerol is technically a compound within the lipid classification, it has the Caloric equivelent of a Carbohydrate (4 Kcal) and Glycerol is about 60% as sweet as sucrose and is used to sweeten as well as to add a chewy texture or “mouth feel” to foods. Also, manufactures of these bars realized that since it is not a carbohydrate, it did not have to be listed in the nutritional information panel. Therefore, a bar’s nutrition label may indicate that there are only eight or ten grams of carbohydrates. This would deceptively be true. However the other thirty grams, would be glycerol.
Most bars on the market no longer deceptively do this. Many people have realized it, and the change has been made. There is now a listing stating that the product contains glycerol. If it is not listed how much is in the product, just add up the ingredients:
280 Kcal : 30 g Protein, 9 g Carbs, 8g Fat.
30 g protein = 120 Calories, 9 g Carbs = 36 Calories, 8 g Fat = 72 Calories = 228 Calories. Therefore, there is a 52 Calorie difference of what is indicated. As I have stated, Glycerol contains four Calories per Gram like Carbs and Protein. This product would essentially have 13 grams of glycerol.
I hope this illustration makes fats easier to understand:
Triglycerides (Fats and oils)
- Fatty Acids
Phospholipids Sterols (Cholesterol)
Because sometimes no matter how much will power you may have, you may want those tempting snack foods such as chips, ice cream, and other desserts, there has been a golden opportunity for companies to develop fat substitutes. How attractive would this be to you to be able to eat these foods without consuming all the fat that is with them?
The idea behind these products is to reduce the fat and calories while maintaining the texture and taste. As promising as that may sound, it is not without controversy and concern. Is anything in this world ever? The question is what effect can these products have on the gastrointestinal tract and can they interfere with the absorption of vital nutrients.
One fat substitute that is used in many products is called Olestra. Olestra is a synthetic chemical combination of sucrose and fatty acids that provides no calories or fat because it is indigestible by the body. The sucrose replaces the Glycerol portion of the fatty acid.
Whenever fat substitutes are used in a product, there is usually a caution that reads,” may cause abdominal cramping, or possible anal leakage”. Hmmm, this sounds intriguing huh? What is messy underwear for five hundred Alex? I have a friend that would eat these products all the time, and it never seemed to bother him. A bunch of us that would hang out together even dared him to eat a whole bag of chips containing Olestra, but still he handled it well. I also know other people who were extremely sensitive to these products and it bothers their stomach to eat even a small amount.