In the previous article, we discussed the complex functions of carbohydrates and proteins. The last macronutrient we need to discuss is fat or lipids. Fat tends to get a lot of "bad press." Actually, as you will see, fats and lipids are essential for optimal health. Besides being a source of energy or calories, some additional, and very important, functions of fats/lipids include:

1. The primary component of cell walls;

2. The compound from which all sex hormones and certain adrenal hormones are made;

3. The compound from which many regulatory substances are made, which help regulate blood pressure, blood clotting, inflammation and the immune response;

4. The compounds making up a large part of the brain and the outer covering of the nerves.

Fats are neither all good nor all bad. Different fats have different effects on the body, and therefore have different purposes when it comes to maintaining health. As with carbohydrates and proteins, the proper balance of dietary fats is very important.

Fat is the common name for this macronutrient, but the more accurate name is lipids. Just as carbohydrates can be either starch or sugars, lipids can be classified as glycerides, phospholipids or sterols. The diet contains all three of these lipids.

Glycerides
Glycerides are the primary lipid found in the diet. Glycerides are made up of two parts: a glycerol with one, two or three fatty acids attached. A glycerol with three fatty acids attached is called a triglyceride. Triglycerides comprise most of what is called "fat" in the diet. Since dietary fats are mostly fatty acids and just a small portion is glycerol, we are going to focus on the function of the fatty acids.

The primary function of fatty acids is to provide long-term energy stores for the body. Though the preferred energy for the body is carbohydrate, carbohydrates cannot be stored in the body in any significant amount. Fat, however, can be stored for a long time in seemingly unlimited quantities. Fat is the body's insurance policy against our dying from starvation.

As discussed in the previous article, the body transfers the energy in food to a molecule called ATP (adenosine triphosphate). Remember, ATP is a molecule that stores the energy from food, so the energy can be used by the cell. Fatty acids can be used by most cells in the body to make ATP. The body only adds to fat stores if more calories are taken in than are necessary to maintain good stores of ATP. Once ATP storage is full, any extra calories will be converted to body fat, regardless of whether the calories come from proteins, carbohydrates or fats.

Fats do supply the most calories per gram. Proteins and carbohydrates supply 4 calories per gram, whereas fats supply 9 calories per gram. Therefore, 2 grams of protein or carbohydrate supply 8 calories, and 2 grams of fat supply 18 calories. This is why the media has placed so much emphasis on reducing fat to lose weight. Most individuals, however, try to lose weight by consuming low-fat foods that are high in sugar. They are really just substituting calories from sugar for calories from fat, and not only do they not lose weight, but they continue to gain weight. There are other problems associated with the "no-fat/low-fat" approach to weight loss. These problems will be addressed when we discuss the balancing of proteins, carbohydrates and fats in the next issue.

Frequently, we read that one type of fat is "good," and another type of fat is "bad." Is one fat really better or worse than another fat? Actually, a fat that is detrimental to one individual may improve health in someone else. Each person's need for fat must be individualized. Not only for the amount of fat, but the type of fat as well.

Good nutrition is profoundly important to maintain our good health and support our healing capacity. However, few of us understand how to eat the appropriate foods in the right proportions. Even when we do, it can be very difficult to follow through and eat in a consistently healthy manner. Furthermore, for the average person, reliable nutritional information is hard to come by. Every season it seems someone comes out with a miracle diet to improve our health. We are often lost in a sea of information that we are ill equipped to fully understand and evaluate. I believe that understanding nutrition is a vital part of achieving and maintaining good health. Over the past 25 years, I have worked with a few physicians and clinical nutritionists who have consistently kept abreast of scientific research and progress in the field. These professionals have routinely integrated new nutritional findings into their work with clients.Inspired by their successes, I urged Joy Bicknell, clinical nutritionist, to prepare this series of articles for my column. Joy and I spent many hours discussing what to include in this series, and how to make it relevant to both the professional and to his or her clients. As you will see, nutritional processes range from the very simple to the profoundly complex. I have divided a large volume of complex material into, what I hope, are small digestible parts (no pun intended). I personally had to read many sections six or seven times to understand them myself. Yet my commitment to learn about this new and beneficial knowledge has positively influenced my own nutritional choices and my own work with clients. I hope this information will contribute to your decisions about your own nutrition as you, along with your clients, focus on achieving a healthier lifestyle. These articles will help you more fully understand that what we eat and drink play a major part in our health and healing capacity. There are specialists with extensive training and knowledge in this area of science. Naturopaths, clinical nutritionists, as well as some physicians, have dedicated a part of their career to gaining an in-depth understanding of nutrition. This prepares them with the knowledge needed to create an appropriate plan of action to address specific nutritional issues. The purpose of this series of articles is to explain how good nutrition can improve your client's ability to heal from pain and injury, as well as optimize his or her health. By publishing these articles, I am not suggesting that practitioners give nutritional advice to their clients. To do this appropriately requires many years of study and training. This information is offered as a resource for you and your clients as you grow in your awareness and understanding, and in the choices you make about your daily nutritional practices. Article 1: Nutritional Basics For Health (Winter 2002) The first article discussed why we eat the foods we do, the body's physiological need for food, the six types of nutrients our bodies need, the function of macronutrients and micronutrients, food quality, including organically grown foods and nutrient density, and the complex functions of carbohydrates and proteins in relation to health and healing. Article 2: The Vital Functions Of Fats (Spring 2002) This article explores, in detail, the many components and functions of fats, which are also known as lipids. Glycerides, phospholipids, sterols, fatty acids and cholesterol are all lipids. Together, these lipids provide "long-term" energy stores, help form and maintain cell walls, form the compound from which all sex hormones and many regulatory substances are produced, and help regulate blood pressure, blood clotting, inflammation and the immune response. Article 3: Balancing The Macronutrients: Carbohydrates, Proteins And Fats (Summer 2002) This article looks at how to balance carbohydrates, proteins and fats in the diet, and explores ways of determining the appropriate quantity of macronutrients, the timing of meals and snacks for optimal benefit, and the importance of insulin metabolism, including health problems associated with chronic low blood sugar. Article 4: The Micronutrients: Vitamins And Minerals (Fall 2002) This article presents the functions of vitamins and minerals, and the important relationship between these micronutrients and macronutrients in the body. It looks at the challenges in obtaining optimal vitamins and minerals exclusively from the foods we eat. Article 5: The Importance Of Water (Winter 2003) The final article discusses the often unrecognized and tremendous importance of water to our bodies. It looks at how water, salt and protein work together to enhance health. It also discusses the importance of water quality and the choices available for water filters and purifiers.

Fatty Acids
There are three types of fatty acids, and you might have already heard of them. Fatty acids are either saturated, monounsaturated or polyunsaturated. (Now, this next statement may bring on memories of chemistry class, but don't let it scare you.) The properties of a fatty acid are dependent upon its molecular structure. The most important component of structure is the number of double bonds in the fatty acid molecule. A saturated fatty acid has no double bonds in its structure. A monounsaturated fatty acid has only one double bond. A polyunsaturated fatty acid has two or more double bonds. The presence or absence of double bonds determines the properties of each type of fatty acid.

All three types of fatty acids are found in every dietary fat. However, it is the predominant type of fatty acid in a dietary fat that determines the effects of that particular fat on the body. If the majority of fatty acids in a particular fat are saturated fatty acids, the fat is labeled a saturated fat. Saturated fatty acids are primarily found in animal fats, for example, butter and lard. Coconut oil and palm kernel oil are the only two plant-based fats that are classified as saturated fats. Saturated fats are very stable. This means they are solid at room temperature, and do not go rancid or "bad" very easily.

Polyunsaturated fats contain mostly polyunsaturated fatty acids. Polyunsat-urated fats have the opposite properties of saturated fats. Most polyunsaturated fats come from plants. For example, vegetable oils and seed oils, such as corn oil and sunflower oil, respectively, are polyunsaturated fats. The only polyunsaturated fats that come from animals are fish oils. Because polyunsaturated fatty acids have many double bonds, they are liquids at room temperature and are very unstable. Because they are unstable, they go rancid very readily.

As you may have guessed by now, monounsaturated fats have a predominance of monounsaturated fatty acids. Monounsaturated fats are found primarily in nuts and olives. Almond oil is the best source of monounsaturated fats, followed by olive oil, avocado oil, macadamia nuts and cashews. The properties of monounsaturated fats fall between those of saturated fats and polyunsaturated fats. Monounsaturated fats are solid when refrigerated and liquid at room temperature. They are less stable than saturated fats but more stable than polyunsaturated fats.

The stability of the fatty acids in a particular fat will influence how quickly the fat breaks down and goes "bad" or rancid. The more saturated fatty acids in a fat, the more stable it is and the more time it takes for it to break down. The more polyunsaturated fatty acids in a fat, the less stable it is and the more quickly it goes rancid. Exposure to light, heat and oxygen will all cause fats to go bad more readily. Therefore, saturated fats can tolerate exposure to higher degrees of light, heat and oxygen without becoming rancid than can monounsaturated fats or polyunsaturated fats. A cup of a polyunsaturated oil, such as sunflower oil, left sitting in a 60ûF kitchen with sun shining in the window will go rancid much more rapidly than will a saturated fat like butter. When a fat goes bad it means the fatty acids in the fat have been damaged.

Now, consider how different fats are treated before they are purchased. Since butter melts when it is exposed to temperatures higher than average room temperature, it is kept refrigerated during processing, shipping and storage. It is packaged in a container that does not let in light. Sunflower oil, on the other hand, is usually bottled in clear glass bottles, thus it is exposed to light. It is also exposed to relatively high temperatures during shipping and storage. And unless the label reads "cold processed," the oil was exposed to high heat during processing. Therefore, by the time you purchase most polyunsaturated oils, like sunflower oil, the oil is already fairly rancid. Once you open the bottle, it is exposed to oxygen, which further increases the rancidity. If the oil is then used for frying or baking, the rancidity increases dramatically.

Why is rancidity of dietary fats so important? To answer this question, we must first consider the role of phospholipids because phospholipids also contain fatty acids.

Phospholipids
Every tissue and organ in the body is made up of cells. Phospholipids are the major component of every cell wall, more accurately termed the cell membrane. The cell wall is very similar to the walls of your house. The outer wall of your house may be made up of clapboards or shingles attached to wood. The inner wall is usually made of painted sheetrock or paneling. The major difference between the house wall and the cell wall is that both the inner and the outer membrane of the cell wall are made of the same component--phospholipids. The walls of the house allow us to control the environment within the house. We take out the garbage and control the temperature, as well as the movement of people and animals in and out of the house. It also allows us to keep out dirt, rain, snow, etc. The cell membrane has the same purpose. It keeps necessary nutrients and other compounds in the cell and moves unwanted wastes out of the cell. The integrity of the cell membrane is dependent on the quality of the fatty acids in the phospholipids that make up the cell membrane.

Now we can get back to the rancidity question. Phospholipids make up the cell membrane. Every phospholipid has two fatty acids that are supplied by dietary fats. If you eat rancid fats, you will have weak and damaged fatty acids making up your cell membranes. How well can a cell membrane do its job if it is made up of damaged fatty acids? Not very well. It is like a house in the summer with walls that are rotting and leaving holes. The cool air-conditioned air flows out, the mosquitoes move in, and the environment is no longer very hospitable. The same thing happens to the cell. The needed nutrients move out, the balance of one nutrient to another is compromised and efficient cell function is lost. Once the function of enough cells is compromised, tissues and organs no longer function well, and you start to develop symptoms. If the damaged fatty acids in the cell membrane cannot be replaced with undamaged fatty acids, pathology and disease develop. Therefore, the quality of dietary fats is very important for healing and maintaining a healthy body.

Farm-Raised Salmon: The Need For And Quality Of Fatty Acid Supplements The plant life eaten by cold-water fish supply the linolenic acid, which the fish convert to EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). On the West Coast of the United States, it is very easy to obtain "wild" salmon. On the East Coast, the vast majority of available salmon is "farm-raised." Most farm-raised salmon are fed grains that do not supply linolenic acid, and therefore farm-raised salmon do not contain an abundance of EPA and DHA. Is it beneficial to supplement the diet with fatty acid supplements? This brings up the question of the quality of fish oil supplements, in particular, and fatty acid supplements, in general. The fatty acids in fish oil are polyunsaturated fatty acids. So are the fatty acids in flax oil, borage oil, black currant oil and evening primrose oil, all of which are used as fatty acid supplements. Because they are polyunsaturated fatty acids, they go rancid very easily. Many fatty acid supplements have a high degree of rancidity, and therefore supply damaged fatty acids to the body. Therefore, it is very important to call the company who makes the fatty acid supplement, and request a copy of an independent assay stating the level of peroxides and percent rancidity of the fatty acids in their product(s). All fish oil supplements should be processed via molecular distillation to remove any PCBs that may be found in the oil of the fish. It is best that fish oil supplements come from deep-water fish, not coastal fish, to ensure the lowest possible level of heavy metals that may concentrate in fish that feed along the coastline.