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Mainely Tipping Points 14: Good Fats, Bad Fats

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Mainely Tipping Points 14

Good Fats, Bad Fats

           

Since the late 1970s, Americans have been encouraged by nutritionists, doctors, the government, and industry to eat less fats, especially the saturated fats once traditional in the American diet.  Yet, according to Dr. Mary Enig, an expert in the chemistry of fats, and Sally Fallon, both of the Weston A. Price Foundation, saturated fatty acids constitute at least 50 percent of our cell membranes and are what give our cells necessary stiffness and integrity.  Saturated fats play such an important role in the health of our bones that at least 50 percent of our dietary fats should be saturated.  And among their many other benefits, saturated fats enhance our immune systems (“The Skinny on Fats,” http://www.westonaprice.org/know-your-fats/526-skinny-on-fats.html). 

Today, Americans are deficient in the healthy fatty acids which support the healthy functioning of their bodies.

Beginning in 1980, the government recommended a diet which substituted carbohydrates for healthy fats and which has resulted in national obesity and chronic disease problems—as many scientists of that era feared.  The fats Americans now consume most often are denatured, highly refined, highly unstable, and are too rich in omega-6 fatty acids. 

So, what kinds of fats are healthy and necessary for humans?  Caroline Barringer, writing in the current July/August 2010 issue of WELL BEING JOURNAL and drawing on the work of Enig and Fallon, walks readers through the healthy fats terrain in a few short pages  (“Fats:  Safer Choices for  Your Frying Pan & Your Health,” 30-38).  You can buy a copy at Good Tern, Fresh Off the Farm, or online.  Enig and Fallon’s fully comprehensive information is available on-line.  See, especially, “The Skinny on Fats” and “The Oiling of America” at http://www.westonaprice.org

Understanding the chemical structures of fats and what industrial processing does to those structures helps one begin to understand which fats are dangerous and why.  Remember, Barringer reminds, that all fats are combinations of the following fatty acids.  For instance, beef tallow (which most of us use only to feed our birds in winter) is very safe for cooking and frying and is 50 to 55 percent saturated fat, 40 percent monounsaturated fat, and only 3 percent polyunsaturated fat.

Saturated fatty acid (SFAs) molecules are straight so can stack together tightly, which is why they are solid or semi-solid at room temperature.  The straight nature of SFA molecules makes them very stable, even at high temperatures, and they do not turn rancid easily.

Monounsaturated fatty acid (MUFAs) molecules have a slight bend.  They can still stack closely, but not as tightly as saturated fatty acid molecules, which is why they are liquid at room temperature, but semi-solid when refrigerated.  MUFAs are relatively stable and do not turn rancid easily.

Polyunsaturated fatty acid (PUFAs) molecules have two bends.  They cannot stack together well.  They are unstable, even at room temperature, and are easily damaged by heat, light, moisture, and exposure to oxygen.  They require refrigeration and turn rancid quickly and easily.  Omega 3 and 6 essential fatty acids are in the PUFA category.  But, consume only small amounts of some PUFAs and only if they are organic, unrefined, first cold-pressed or cold pressed, or expeller pressed, or extra virgin. 

 Industrial processing methods affect radically the structure of fats.  Traditionally, Barringer notes, seed and nut oils were extracted by pressing.  Industry crushes the seed/nuts; heats them to 230 degrees or more; presses them using high-pressures to squeeze out all fats, which generates further heat; and uses hexane (a solvent) to extract the last bits of oil.  (Hexane, a petroleum derivative, may cause infertility and central nervous system depression.)  Industry attempts to “boil off” the hexane, but some remains.  If the seeds/nuts are not organic, the hexane acts as a magnet for the chemicals sprayed on the nuts/seeds.  So, the final product is rancid, refined so no nutrients remain, and poisoned. 

Further, Enig and Fallon explain that the damaged molecules form “free radicals” with edges like razor blades.  Barringer notes that these free radicals “wreak havoc on the body, attacking and damaging DNA/RNA, cell membranes, vascular walls, and red blood cells,” which, in turn, leads to further problems.”  

Some of these highly processed oils, which are mostly PUFAs,  then undergo hydrogenation, which transforms oils that are liquid at room temperature to solids, which extends shelf life.  Margarine and shortening, for instance, are hydrogenated PUFA oils.  (MUFAs and some SFAs can be hydrogenated.)  Tiny particles of nickel oxide are added to the oil, then the mixture is exposed to hydrogen gas in a high-heat, high-pressure reactor which chemically straightens any bends in the molecule.  These altered molecules are trans fats.  Now, the oil is thin, watery, and smells foul as it is rancid.  Multiple thickeners and fillers are added, and the oil is steam cleaned (more heat) to remove the odor.  The grey-colored oil is bleached.  The resulting substance is vegetable shortening.  Artificial colors and flavors can be added to produce margarine. 

Our bodies, Barringer explains, do not recognize these kinds of fats as foods.  If we consume them regularly, “we lose the ability to utilize healthy fats properly.”   Further, when healthy fatty acids are displaced by these highly processed fake fats, our bodies become subject to cascading, serious health problems, like cancer, diabetes, birth defects, sexual dysfunction, heart disease, and poor bone health. 

So, Barringer warns, avoid trans fats “like the plague”—which is not easy because the FDA allows industry to claim “zero trans fats” when trans fats are present.  Read labels and look for hydrogenated oils, which are trans fats.  Do not buy products where the following words appear on the label:  refined, hydrogenated, partially hydrogenated, or cold-processed (which is not cold- pressed.)

The safest fats for cooking are lard (pork fat); ghee (melted butter with the milky solids skimmed); tallow (beef and lamb fat); chicken, duck, and goose fat; coconut oil (organic and virgin); and red palm oil or palm kernel oil (organic and virgin).  You can, also, combine these fats.  Barringer likes coconut oil (92 percent saturated fat with powerful antimicrobial and antifungal properties and lauric acid–a medium chain fatty acid found in breast milk) combined with ghee or lard.  (I buy coconut oil by the case online from Wilderness Family Naturals.)  Barringer says red palm oil has a “pungent, paprika-like flavor” that is “best suited for roasting root vegetables,” like roasting red and white potatoes; red, yellow, and orange peppers; fresh garlic, and herbs.

Properly pressed olive oil, peanut oil, avocado oil, macadamia nut oil, and sesame oil are good for stir-frying.  Peanut oil should have limited use as it has a high percentage of omega-6 fatty acid. 

The following oils are unsafe for any kind of heat exposure:  vegetable/soybean oil, corn oil, flax oil, hemp oil, pine nut oil, pumpkin oil (roasted or raw), safflower oil, sunflower oil, and grapeseed oil.  These oils are almost 50 percent omega-6 fatty acids and should be consumed in moderation.  It is hard to find unprocessed versions.  Also, corn and soybean oil should be avoided as they are likely to be genetically modified and are grown with heavy pesticide levels.

Barringer, like Enig and Fallon, concludes that canola and cottonseed oil are unsafe to consume under any circumstances.  Canola is a highly processed industrial oil and does not belong in the human digestive tract.  Plus it is almost entirely a genetically modified crop.  Cotton is “one of the most genetically modified, pesticide-laden crops in America.”  And, asks Barringer, “when did cotton and its seed become a food?” 

Butter, especially real butter, is practically a medicine.  Butter, Barringer explains, is a cofactor that allows our bodies to utilize effectively calcium and other minerals we consume.  Butter contains omega-3 and omega-6 fatty acids in small amounts in a healthful ratio.  Butter contains conjugated linoleic fatty acids (CLA) for better weight management, muscle growth, and protection from cancer.  Butter contains the fat-soluble vitamins A, D, E, and K that help us absorb the trace minerals it also contains, among them zinc, selenium, iodine, chromium, and manganese.  Butter contains butyric fatty acids that provide “proper inflammatory and anti-inflammatory responses to help us heal effectively.”  And, the fat in butter “enhances brain function and increases cell membrane integrity.”    

Eat organic butter!  Eat lots of it every day, especially if you can find raw butter.  (But, not with a lot of bread, which is a carbohydrate.)

Mainely Tipping Points 13: The Failure of the Low-Fat, High-Carbohydrate American Diet

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(Oops!  Read TP 12 first; it’s part of a series in the essays) 

Tipping Points 13

The Failure of the Low-Fat, High-Carbohydrate American Diet

 

 When Luise Light and her team of experts attempted to scientifically formulate the 1980 USDA Food Guide, they accepted two current dietary ideas as truth:  fat should be no more than 30 percent of the diet, and since the end of World War II, and especially in the 1960s, Americans had been experiencing “rising rates of heart disease, high blood pressure, stroke, and diabetes” (13, Luise Light, WHAT TO EAT:  THE TEN THINGS YOU REALLY NEED TO KNOW TO EAT WELL AND BE HEALTHY).

Current historians show us that the low-fat premise that has governed the American diet for the past fifty years sprang from belief, not science, and became part of American cultural and economic practices when the stars aligned around a constellation that included the political power of a congressional committee, media acceptance of its recommendations, and the firmly-held beliefs of a handful of people.

Science writer Gary Taubes, in his myth-exploding article “The Soft Science of Dietary Fat,” published in “Science” magazine in March 2001, questioned the idea that there ever was an epidemic of heart disease after World War II (http://www.nasw.org/awards/2001/The%20soft%20science.pdf).  When Taubes interviewed Harry Rosenberg, Director of the National Center for Health Statistics (NCHS), Rosenberg said a heart disease epidemic never existed.  First, in 1949 the International Classification of Diseases (ICD) added arteriosclerotic heart disease as a new category under the general category of heart diseases.  Between 1948-1949, the new category appeared to raise coronary disease death rates about 20 percent for males and 35 percent for females. 

Again, In 1965, the ICD added a category for coronary heart disease, which added more deaths to the statistical data as physicians began using the new categories.  Furthermore, Rosenberg explained, by the 1950s, Americans were healthier, so more were living to be 50-year-olds who would go on to die of chronic diseases like heart disease, which physicians were now listing on death certificates under the new categories.  Taubes reports that Rosenberg said that, in actuality, risk rates of dying from a heart attack remained unchanged.

Taubes also discussed the fact that between 1989 and 1992, three independent research groups (Harvard Medical School; The University of California, San Francisco, funded by the U.S. Surgeon General’s Office; and McGill University, Montreal) used computer models to work out added life expectancy for a person eating a low-fat diet that controlled saturated fats.  All three models agreed, but their conclusions have been ignored by media. 

The Harvard study showed that if a person’s total fat consumption was less than 30 percent of their daily total calories and if their saturated fat consumption was 10 percent of that 30 percent, a healthy nonsmoker might add from 3 days to 3 months of life.  The latter two studies showed net increase of life expectancy would be from three to four months.  Taubes noted that the U.S. Surgeon General’s office tried to prevent the University of California study from being published in “The Journal of the American Medical Association (JAMA), but JAMA published it in June 1991.

The Lipid Hypothesis is the “scientific” paradigm calling for a low-fat diet.  The Lipid Hypothesis is the premise that ingested fat, especially saturated fat, raises blood cholesterol levels, and high cholesterol levels cause chronic heart disease (CHD).  Yet, many, many scientists now have argued that these cause-and-effect links have never been proven and, in fact, cannot be proven.  More recently than Taubes, Michael Pollan, in IN DEFENSE OF FOOD (2008), traces this history and current thinking on dietary fats in a section entitled “The Melting of the Lipid Hypothesis” (40-50). 

So how did the Lipid Hypothesis and the low-fat paradigm get installed with scant scientific data to support it?  Biochemist Ancel Keys is a key player.  In the mid 1950s, Keys (University of Minnesota) claimed that his epidemiological Seven Countries Study showed a correlation between the consumption of dietary fat and heart disease.  But, an epidemiological study cannot control or eliminate variables, and correlation is not proved causation.  Furthermore, many now, among them Taubes and Uffe Ravnskov, claim that Keys eliminated countries whose statistics did not fit his hypotheses, like France, Holland, Switzerland, Norway, Denmark, Sweden, and West Germany, where national populations ate 30 to 40 percent of their calories as fat and whose death rates from CHD were half that of the United States.  Nevertheless, in 1961, the American Heart Association began advocating low-fat diets for men with high cholesterol levels.

Also in the 1950s, Nathan Pritkin, was diagnosed with heart disease.  Though he had no college degree and no scientific training, Pritkin created and published a low-fat, aerobic exercise regime that sold millions of copies.  Pritkin also suffered from leukemia, and it began causing complications and pain in the early 1980s.  Pritkin committed suicide in 1985.        

In 1977, the Congressional Select Committee on Nutrition and Human Needs, chaired by Senator George McGovern, promoted the low-fat hypothesis—despite objections by scientists expert in the field.  Taubes determines that “a handful of McGovern staffers…almost single-handedly changed nutritional policy in this country” by initiating “the process of turning the dietary fat hypothesis into dogma” (4).

In 1976, Taubes reports, after two days of testimony, this committee turned “the task of researching and writing the first `Dietary Goals for the United States’” over to Nick Mottern, a labor reporter with “no experience writing about science, nutrition, or health” (5).  Mottern relied on Harvard School of Public Health nutritionist Mark Hegsted’s low-fat beliefs.  Hegsted, unlike E. H. Ahrens, whose laboratory at the Rockefeller University in New York City was doing seminal research on fat and cholesterol metabolism, saw no risks associated with such a major change to the American diet.  Ahrens, as early as 1969, was concerned that eating less fat or changing the proportions of saturated to unsaturated fats could have profound and harmful effects on the body (3-6).  Nevertheless, the Select Committee published Mottern’s dietary guidelines. 

Next, Taube relates, Carol Tucker Foreman, a political appointee at USDA who later forms a public relations and lobbying firm whose clients have included Phillip Morris, Monsanto (bovine growth hormone), and Procter and Gamble (fake fat Olestra), hired Hegsted to produce “Using the Dietary Guidelines for Americans,” which supported the McGovern Committee Report.  Foreman hired Hegsted despite the fact that Philip Handler, National Academy of Sciences (NAS) President and an expert on metabolism, had told her that Mottern’s Dietary Goals were “`nonsense’ “ (6).

When NAS released its own dietary guidelines a few months later (watch your weight and everything else will be all right), the media criticized the NAS for having industry connections.  Hegsted later returned to Harvard where his research was funded by Frito-Lay.

So, a consensus was achieved, oneTaube says is “continuously reinforced by physicians, nutritionists, journalists, health organizations, and consumer advocacy groups such as the Center for Science in the Public Interest” (1).  And, science was “left to catch up” (7).

 Only, science never has.  And, what has emerged is that all calories are not equal and substituting carbohydrates for fat has caused weight gain and diabetes.  And, according to lipid biochemist Mary Enig, substituting highly-processed fats for time-honored, traditional fats is causing chronic heart disease.   

Pollan notes that in a 2001 review of the relevant research and report by “prominent nutrition scientists” at the Harvard School of Public Health, “just about every strut supporting the theory that dietary fat causes heart disease” was removed, except for consuming trans fats and consuming fats that alter ratios of omega 3 to omega 6 fatty acids (41-42).  Pollan notes the Harvard scientists stated the following in their report’s second paragraph:  “`It is now increasingly recognized that the low-fat campaign has been based on little scientific evidence and may have caused unintended health consequences’ “ (43).    

Pollan assesses that the low-fat ideology of nutritionism has been nutrition’s “supreme test and, as now is coming clear, its most abject failure” (41).