With the current constant push to reduce the intake of fats in the diet, it is easy to forget certain fats are essential for health. Likewise, as pointed out in a previous [April 2012 Food: Combining and Timing For Health] article on food combining, fats often are blamed for what are, in fact, the consequences of the consumption of sugars, especially fructose, and refined carbohydrates. A number of cultures around the world defy the American paradigm that eating fat makes one fat.
For instance, the French in general show the diseases of excess and of age both less and at a later point of their lives than do their American counterparts; they are healthier and they live longer despite smoking far more. Why? Seemingly paradoxically, the French eat four times as much butter as we do, more than twice as much cheese (commonly 60 or even 75 percent butterfat) and about the same number of calories. Indeed, the French eat more than twice the animal fats and only two thirds the supposedly healthful vegetable oils that Americans eat. Strikingly, the French eat only one eighteenth — that is right, only 5.6 percent! — the sugar consumed in this country. (We Americans, like the British, are notorious for our love of sugar.) Frenchmen even eat only about one half the fruit which we consume, and therefore about one half the fructose from that source. On the other side of the ledger, the French consume more vegetables, more fish, more grains, more potatoes and more of other complex carbohydrates. They also do not snack between meals, a habit that has been shown in overweight individuals to increase the total daily consumption of calories. (In the “grazing” versus “gorging” debate, when diabetics were tested with the move from three meals to nine meals per day in a one month study, as opposed to very short studies of one to a few days, the grazing approach did not improve glycemic control.)
All of this suggests that it is the American diet, one simultaneously high in both fats and simple carbohydrates, which bears a large degree of responsibility for American weight problems. And lest the reader think the French are the only exception, it should be pointed out the Swiss, who are second only to the Japanese among industrialized countries in life expectancy, eat even more in the way of cheeses, butter and cream, sausages, etc. than do the French. I examine these issues in detail in two books on the topic of weight loss, Anti-Fat Nutrients (4th edition reissued 2010) and User’s Guide to Weight-Loss Supplements.
Does the nature of the fats consumed matter? Yes, certainly. Those rich French cheeses, for example, are much more likely than American cheeses to be from cows that ate grass, hence have a different make-up of fatty acids. And the French eat more fish, meaning that they naturally consume more of one family of essential fatty acids than do Americans. Both of these factors are important.
The essential fatty acids (EFAs) must be supplied from the diet. Other fats, although not essential, are powerful health promoters. Both essential and nonessential fats are required for the absorption of fat-soluble vitamins and related nutrients. The two families of EFAs are the omega-6 family based upon linoleic acid (LA) and the omega-3 family based upon alpha-linolenic acid (LNA). The essential fats make up significant portions of the nervous tissue of the brain and elsewhere. They are building blocks for the body’s production of hormones (including the sterol hormones such as testosterone and estrogen) and the production of hormone-like signaling compounds (such as prostaglandins). The immune system is regulated by essential fatty acids and compounds made from them. Hence, the essential fatty acids are primary movers in normal physiology.
The Omega-6 Fatty Acids
Gamma-linolenic acid (GLA) is an omega-6 family fatty acid nutrient. Under ideal circumstances, it is made in the body from the conversion of linoleic acid, which is common in many seed oils. GLA serves as a precursor to the family of hormone-like substances or “activated fatty acids” known as the prostaglandin (PG) series called PGE-1. This means the prostaglandin family “E” derived from GLA. The PGE-1 family is involved in anti-inflammatory, anti-spasm, anti-infection and similar actions in the body, including reducing the “stickiness” of the blood. PGE-1, in other words, is a family of “good” compounds made from omega-6 fatty acids.
Unfortunately, there is also a “bad” set of compounds that is made from omega-6 fatty acids, as well. The second family of prostaglandins (PGE-2) made from the omega-6 linoleic acid involves the production of arachidonic acid, a fatty acid already found in pre-formed abundance in the American diet. The PGE-2 series activates aspects of the immune and other systems. In excess, it leads to inflammation, menstrual cramps, asthma, heart disease and many other problems, including obesity. These are all possible results of the chronic activation of what is known as the arachidonic acid cascade. Among its other duties, the PGE-1 family serves to control or to inhibit production of the PGE-2 family.
Most of us need a lot more of PGE-1 and a lot less of PGE-2. However, the common condition known as the metabolic syndrome or Syndrome X turns this equation on its head. High levels of insulin secreted in response to the consumption of refined carbohydrates and sugars strongly increase the production of PGE-2. At the same time, the same factors that produce Syndrome X act against the production of PGE-1.
Many factors can prevent the conversion of linoleic acid to GLA and from there to PGE-1. These factors include deficiencies of the vitamins B3, B6, C and biotin, as well as inadequate intakes of the minerals magnesium and zinc. Too much alcohol, too much saturated fat, the consumption of hydrogenated (trans-fatty acids) and heat-damaged fats and many other dietary factors are involved. Moreover, many people (especially those who tend to put on weight) have difficulty in transforming linoleic acid into GLA simply because they naturally produce relatively little of the enzyme needed for this transformation.
The Omega-3 Fatty Acids
The omega-3 fatty acid alpha-linolenic acid is found abundantly in flax seed oil, whereas docoshexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are found primarily in cold water ocean fish, such as salmon and sardines. Although they are closely related fatty acids, EPA and DHA have somewhat different effects within the body. EPA acts mainly to suppress the arachidonic acid cascade and to increase the production of anti-inflammatory prostaglandins.
DHA has a larger repertoire of uses in the body. For instance, it acts as a source of EPA because it can be reconverted to EPA when needed. However, DHA is far more than merely a potential source of EPA. DHA is critical for the proper functioning of the nervous system. It also has a stronger effect upon blood lipids levels. Although EPA can be converted to DHA, the rate of conversion may be inadequate to meet periods of chronic and/or elevated demand. Therefore supplemental DHA, and not just LNA and/or EPA, may be of importance for maintaining normal health.
As is true of GLA, the transformation of these fatty acids from LNA to EPA to DHA and then to their active antiinflammatory prostaglandins can be blocked by diets low in minerals and high in trans-fatty acids. Hence although flax seed oil as a supplier of LNA may be the least expensive source of omega-3 fatty acids, individuals who need therapeutic levels of supplementation should strongly consider using concentrated sources of EPA and DHA.
There is considerable agreement that for most of human history, and certainly before the advent of cereal grains as sources of cooking oils, the ratio of omega-6 to omega-3 fatty acids in the diet was 3 to 1 or perhaps 2 to 1. In modern diets, the ratio is at least 10 to 1 and perhaps as high as 20 to 1. An excessive intake of LA, especially on refined carbohydraterich diets, promotes heart disease, inflammation, insulin resistance and autoimmune disorders. Modern diets tend toward odd nutrient imbalances: They are high in trans-fatty acids, high in LA, high in refined carbohydrates and rich in preformed arachidonic acid, yet low in omega-3 fatty acids and in minerals. As a result, the pathways to the anti-inflammatory and also thyroid-supporting prostaglandins are either under-fed or blocked.
How Essential Fatty Acids Can Help You Lose Fat
A study conducted in 1979 illustrates the effectiveness of GLA as a nutrient promoting weight loss. In this study, thirty-eight individuals took GLA in the form of evening primrose oil for eight weeks. Of the subjects who were more than 10 percent above their ideal weights, half lost an average of 9 pounds while taking four capsules per day. Only five individuals in the group showed no weight change, and the four subjects who took eight capsules per day averaged a weight loss of 23 pounds. One explanation of the effectiveness of GLA is that it appears to increase the body’s level of brown fat, a type of fatty tissue that actually burns fats for energy rather than storing fat. Brown fat (brown adipose tissue or BAT) is very important for thermogenesis.
GLA also appears to be important for preventing Syndrome X and diabetes. For instance, a low level of GLA available during development in the womb predisposes children to the development of insulin resistance. This bodes ill for children of the current generation of mothers and suggests that we will continue to see an increase in diabetes in the near future.
Omega-3 fatty acids appear to improve insulin sensitivity, to increase the oxidation of fats for fuel, to promote thermogenesis and to help reduce fat storage. Over a period of several months, supplementation with omega-3 fatty acids may improve thyroid functions. EPA and DHA supplementation (4 grams/day) with active diabetics for six weeks has been shown to improve blood lipids, although there was no benefit to glucose control over this period of time. In general, omega-3 fatty acids raise HDL levels. Unlike GLA, omega-3 fatty acids cannot serve as a substrate for the synthesis of arachidonic acid, which is a positive point.
Conjugated Linoleic Acid (CLA)
Conjugated linoleic acid (CLA) is a fatty acid nutrient that occurs naturally in beef and in many dairy products as long as the cows involved were raised on grass. The reason that CLA can be found in meats and dairy products is that it is made from linoleic acid by the bacteria Butyrivibrio fibrosolvens, an organism found in the intestinal tracts of some animals, particularly ruminants, such as cows. Not all meats and oils are sources of CLA, however. Pork, chicken, fish and vegetable oils, for instance, contain very little CLA.
CLA was discovered in the mid-1980s by researchers who found that a compound in beef exerted a cell-normalizing effect. Further investigations indicated that CLA is an immune system modulator — it alters some immune functions and how the body reacts to immune stimulation. Experimentally, CLA has been shown to protect animals against some of the adverse effects of being injected with toxins or certain types of vaccination. It has demonstrated anticancer benefits. Currently, scientists believe that CLA alters the way that fats are broken down and stored in various membranes and tissues. The ratio of saturated fats to monounsaturated fats in tissues is altered in a favorable manner. The effect of this change in the several species of animals studied is a reduction in food consumption, a reduction in stored fat, a better ratio of high density lipoprotein cholesterol (HDL, the “good” cholesterol) to low density lipoprotein (LDL) and total cholesterol, and a reduction in atherosclerosis.
The results of recent clinical trials with CLA have been mixed with regard to weight loss and Syndrome X. Although supplementation yields health benefits through the promotion of greater leanness, lower body weight in diabetics and even anti-inflammatory effects, at least in males already experiencing Syndrome X, results have been slightly increased insulin resistance. This suggests that CLA might best be utilized for its virtues (promoting leanness, anticancer, etc.) in conjunction with other supplements that directly address blood sugar regulation, such as chromium. CLA can be supplemented preformed or the body can make its own from a precursor (punicic acid) found in sunflower seed oil and pomegranate seed oil.
Supplementing Fats for Weight Loss
GLA appears to be more important for improving weight control than are the omega-3 fatty acids. It is found in significant amounts in human mother’s milk, in the seed oil of the evening primrose plant, borage oil, and in black currant seed oil. Doses from 90 milligrams to more than 400 milligrams of GLA have proven effective. This is the amount of GLA found in 2–8500 milligram capsules of evening primrose seed oil. Some individuals may find that they receive benefits only at the higher dosage range. GLA is often more effective when taken in conjunction with vitamin B6 and vitamin E. Because in modern Western diets omega-3 fatty acids are almost always underrepresented and GLA (an omega-6 fatty acid) will do nothing to correct this imbalance, dieters should supplement with 2–3 grams of high potency/high purity omega-3 fatty acids from fish oil each day (500–1,000 milligrams with each meal) and/or add flax seed oil (1–2 tablespoonsful) to the diet. Ground or cracked flax seed supplies lignans and other healthful ingredients, but usually should not be consumed in amounts greater than 4 tablespoonfuls per day on a chronic basis inasmuch as an excess may reduce thyroid hormone function.
GLA has been reported to give rise to occasional mild acne. In the experience of one clinical weight loss physician, large doses given to improve weight loss also may lead to increased susceptibility to bruising in a small number of individuals. GLA and the omega-3 fatty acids are polyunsaturated fatty acids and therefore need protection against oxidation and free radical damage. They should be taken together with antioxidant supplements such as astaxanthin (4 mg or more daily) grape seed extract polyphenols (100–300 milligams) and/or alphalipoic acid (50–300 milligrams) daily to guard against this. Also, concurrent intake of omega-3 fatty acids plus broadspectrum antioxidant and vitamin/mineral supplementation helps to prevent GLA from being transformed into arachidonic acid and the “bad” prostaglandins.
Individuals who are taking prescribed blood thinners should consult their doctors before adding essential fatty acids to the diet in any quantity. As indicated above, both GLA and the omega-3 fatty acids act as natural blood thinners and anticoagulants. It is in part because of the imbalance in and lack of essential fatty acids in the American diet that blood thinning medications are so commonly required.
Dallas Clouatre, PhD
Dallas Clouatre, Ph.D. earned his A.B. from Stanford and his Ph.D. from the University of California at Berkeley. A Fellow of the American College of Nutrition, he is a prominent industry consultant in the US, Europe, and Asia, and is a sought-after speaker and spokesperson. He is the author of numerous books. Recent publications include "Tocotrienols in Vitamin E: Hype or Science?" and "Vitamin E – Natural vs. Synthetic" in Tocotrienols: Vitamin E Beyond Tocopherols (2008), "Grape Seed Extract" in the Encyclopedia Of Dietary Supplements (2005), "Kava Kava: Examining New Reports of Toxicity" in Toxicology Letters (2004) and Anti-Fat Nutrients (4th edition).