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Monday, December 30, 2013

Animal Fat in our Diets

Yesterday's Blog posting (see Dietary Fat:   Cure or Curse?) covered the quackery of  Keyes on dietary fat and cholesterol, and the terrible impact it has had on the entire world for more than 60 years.

Today, we will contrast and compare the pros, cons, and differences between dietary fats sourced from chicken, beef, and pork.

This is an extremely complex subject, yet the Supply Management Mafia (#ChickenMafia, #EggMafia, #TurkeyMafia, and #DairyMafia) mess around with our food, changing the animal's metabolism at their whim so as to maximize their profits, regardless of the Frankenstein-like effects on the resulting foods that are produced.  After the #ChickenMafia gets done maximizing their profits, is what they sell to us still food?

Even more important, is it nutritious food?

Eating Fat
We must have fat in our diets. Between 1929 and 1932, Burr and Burr showed that restricting fat from animal's diets led to a deficiency disease, and they were the first to describe essential fatty acids.  Essential Fatty Acids ("EFA's) are essential because the human body cannot synthesize them, so we must obtain them through a balanced diet.

Triglycerides and fatty acids are different forms of similar fat molecules, and are changed back and forth between these two forms of fat by our bodies, depending upon what the body needs the most at that moment in time.   Healthy Eating explains that:
"The triglycerides in the foods you eat are too large for the cells of your small intestine to take in. Digestion reduces these [triglyceride] molecules to fatty acids and monoglycerides small enough for absorption. By mixing with bile secreted from your liver, the fat molecules become water soluble enough for the digestive enzyme lipase to access the fat and break down each triglyceride."
Those fatty acids, monoglycerides (and diglycerides which weren't mentioned above), are absorbed by the small intestine and formed with cholesterol and a protein backbone into chylomicrons, which get transported by the lymph system, and eventually go into the blood stream.  The blood distributes the chyomicrons throughout the body to all cells in need of energy, including the heart, liver, fat cells, and muscle where they deliver triglycerides that are used as cellular energy, and/or are further reacted into other simpler and/or more complex molecules that the body needs.  Once the triglycerides have been delivered, the remnants of the chylomicron are recycled by the liver.

Omega-3 Fatty Acids

Most scientists agree that Omega-3 fatty acids are important in our diets for cellular health, and disease prevention. Omega-3 fatty acids are Essential Fatty Acids ("EFA's).  Omega-3's come in 3 varieties:
  • ALA (alpha-linolenic acid), is a poly-unsaturated fatty acid ("PUFA"), which is mainly plant sourced from flax seeds, walnuts, etc.  ALA is used to form EPA (see next item in list). Don't confuse linoleic acid ("LA") with alpha-linolenic acid ("ALA"), as LA is an Omega-6 fatty acid.

  • EPA (Eicosapentaenoic acid), is a Poly-unsaturated fatty acid ("PUFA"), derived from human breast milk, edible seaweed, and oily cold water fish.  EPA is formed from ALA.  EPA is used by the human body to create DHA.  EPA has some beneficial health effects against inflammation, hyperactivity, chemotherapy adjuvent, and liver health.

  • DHA (Docosahexaenoic acid), is a poly-unsaturated fatty acid ("PUFA"), comes from human breast milk, synthesized by the human body from EPA, or dietary cold water fish oils that are consumed.  DHA has been shown to be helpful to fight some cancers, Alzheimer's, and possibly ADHD (hyperactivity). 
ALA, EPA, and DHA are all active in the formation of eicosanoids (a.k.a. icosanoids); see below

Omega-3 to Omega-6 Ratios
Wiki says that modern Western diets typically have ratios of omega-6 to omega-3 in excess of 10 to 1, some people as high as 30 to 1, partly due to cheap corn oil which has an omega-6 to omega-3 ratio of 49:1. The optimal ratio is thought to be 4 to 1 or lower.  While the Omega-6:Omega-3 ratio is important, the total amount consumed of either fatty acid is also important, as excessive consumption can be a health problem too.
Figure 1: from Stephan Guyenet

Stephan Guyenet looked at the research done on the composition of human body fat over time.  There is a disturbing change in human body fat composition over the last 47 years.  Note that this period is the same period during which many diseases have increased to pandemic proportions (eg. obesity, diabetes, cardiovascular disease, high blood pressure, rheumatoid arthritis, Metabolic Disease, Alzheimer's Disease, etc.).  Looking at Figure 1, each of the dots represent a separate study showing the %  linoleic fatty acid (%LA, an Omega-6 fatty acid known for causing inflammation related diseases) in human subcutaneous fat (21, 22, 23, 24, 25, 26, 27) as shown in Figure 1, plus one study (28) of comparative chimpanzee data..  Linoleic acid in human breast milk has also increased quite a bit over the same time period (29).

This data seems to suggest we are overdosing on Omega-6 vegetable oils in our diet, and the damage is accumulative over time.  Secondly, the factory farms of N. America have significantly changed the animal fat composition over the last 50 years, dramatically raising the linoleic acid content of these animals, and therefore in turn, the linoleic acid content of the factory meat that most persons eat.

San Francisco Chronicle reports:
"The biggest sources of linoleic acid in the American diet tend to be processed foods. The top sources of dietary linoleic acid in America include chicken and chicken dishes [emphasis by SFPFC], grain-based desserts, salad dressing, potato and corn chips, pizza, bread, french fries and pasta dishes, according to the National Cancer Institute. Mayonnaise, eggs, popcorn and processed meats are also significant sources."
"The reason many of the above foods contain linoleic acid is because they're made with vegetable oil. In America, "vegetable oil" tends to refer to soybean, corn and safflower oils, all of which contain a high percentage of linoleic acid. About 75 percent of the fatty acid content in safflower oil comes from linoleic acid; for corn and soybean oil, it's between 55 and 60 percent. One tablespoon of safflower oil contains about 10 grams linoleic acid. Sunflower oil contains about 9 grams linoleic acid per tablespoon; corn and soybean oil 7 grams; and sesame oil 5.6 grams."

"Nuts and seeds with high linoleic acid content include sunflower seeds at 9.7 grams per 1-ounce serving; pine nuts, 9.4 grams; pecans, 6.4 grams; and Brazil nuts, 5.8 grams. The linoleic acid content of dairy and meat products varies based on the diets and lifestyles of the animals they come from. A study published in the "Journal of Dairy Science" found that, on average, the linoleic acid content of cheeses ranges from 3.5 to 8 grams per serving. Blue, brie and Swiss cheeses had higher linoleic acid content than other types. The linoleic acid content in milk ranged from 3.4 to 6.4 grams per serving."
Dietary Omega-6 fatty acids are usually consumed as vegetable oils (eg. deep fat frying, salad dressings, snack foods, and processed foods).  We'll discuss this tomorrow. 

All of the Omega-6:Omega-3 fat ratios for various animal sources can be significantly shifted by what the animal has been fed during its raising (eg. agricultural factory owners feeding their animals the slaughter by-products such as hooves, lungs, bones, hides, feathers, chicken manure, unfit or stale candy, sawdust, used deep fat fryer oils, stale bake goods, beer and alcohol by-products, green pasture grass, hay, grain fed, grain-finished, kitchen scraps, restaurant plate scrapings, ground up dead animals, etc.).  In addition, many of the Supply Management Mafia feed a multitude of drugs and chemicals to their animals so as to maximize their profits.  For example:
  • Mercola states that grass-fed beef is much higher in Omega 3 than fish, with a Omega-6:Omega-3 ratio of 0.16 to 1. This information is from a study done at Iowa State University in August 2001.  This is supported by a separate 2006 study of Australian beef.

  • A 2010 study supported these previously mentioned studies, and also found that compared to grain-fed feedlot beef, grass-fed beef had significantly higher Vitamin A, Vitamin E, antioxidants, and conjugated linoleic acid ("CLA", conjugated meaning that the double bonds and single bonds alternate, such as DSDSDS.  CLA's have been found to have very positive health impact, such as preventing cancers.  See CLA's described further below).

  • Another study found that beneficial Omega-3 fatty acids dropped continuously in the beef muscle tissue, the longer the steer was in residence on a grain-fed feedlot.  See Figure 2
    Figure 2 (from http://www.eatwild.com/images/gr_nutrition2.gif )



















Eicosanoids

Wikipedia says:
"Eicosanoids are signaling molecules made by oxidation of 20-carbon fatty acids. They exert complex control over many bodily systems, mainly in inflammation or immunity, and as messengers in the central nervous system. The networks of controls that depend upon eicosanoids are among the most complex in the human body.

Eicosanoids are derived from either omega-3 (ω-3) or omega-6 (ω-6) fatty acids. The ω-6 eicosanoids are generally pro-inflammatory [ie. they cause inflammation]; ω-3s are much less so. The amounts and balance of these fats in a person's diet will affect the body's eicosanoid-controlled functions, with effects on cardiovascular disease, triglycerides, blood pressure, and arthritis. Anti-inflammatory drugs such as aspirin and other NSAIDs act by downregulating eicosanoid synthesis."
Both Omega-3 and Omega-6 compete for the limited supply of intermediary metabolites that must be shared in the formation of their respective eicosanoids.  Due to this poor starting point (ie. there is a dietary excess of bad Omega-6 in the typical diet), therefore limiting the formation of eicosanoids will tend to be more limiting on the Omega-6 eicosanoid formation on a relative basis, thereby significantly reducing the Omega-6 eicosanoids that are associated with inflammation and cardiovascular disease.

As an example of this process, Aspirin thins the blood (making it easier to pump so blood pressure drops), reduces inflammation, and limits the formation of eicosanoids (which is mainly Omega-6 eicosanoids as discussed above), thereby significantly improving overall health, reducing heart attacks and strokes, reducing mortality, and extending the high quality years of life.  That is the justification behind prescribing the taking of a baby aspirin every day, which is now used by millions of people around the world.
Conjugated Linoleic Acid ("CLA")

Wikipedia describes the discovery of CLA, as follows:
"In 1979, researchers from the University of Wisconsin applied a beef extract to mice skin. The mice were then exposed to a strong carcinogen. When the researchers counted the number of tumors developed by the mice 16 weeks later, they found to their surprise that the mice exposed to the beef extract had 20% fewer tumors. The identity of this anticarcinogen was not discovered until almost a decade later, in 1987. Michael Pariza, the scientist who discovered CLA, later remarked that 'few anticarcinogens, and certainly no other known fatty acids, are as effective as CLA in inhibiting carcinogenesis [ie. CLA stops or slows the formation of cancers] in these models.' "
Since then, there is a growing body of research on CLA's, both from naturally occurring CLA's in foods, as well as dietary supplements.

Other researchers have found CLA effective for treating or preventing cancer, inflammatory bowel disease, Crohn's Disease, % body fat regulation, enhancing human breast milk, BMI (Body Mass Index) control, and enhancing lean muscle development.

Generally, CLA's only occur in animal fats and meat, but two mushrooms have been found that also contain significant levels of CLA, Agaricus bisporus (a.k.a. white mushroom, common mushroom, button mushroom, crimini mushroom, Portobello mushroom) and Agaricus subrufescens (a.k.a. almond mushroom); both of which are rare non-animal sources of CLA.

Kangaroo meat has the highest natural concentration of CLA's, but grass-fed animals (ie. beef, pork, chicken, etc.) have CLA levels that are naturally 3 to 5 times higher than the factory farm and their typical commercial methods using grain feeds and/or silage.  CLA also occurs in eggs from pastured chickens, and can be a significant dietary source of CLA on a natural basis.

CLA is another clear advantage of the small flock, pastured animals methodology.

Animal Fats
Figure 2 (from http://www.eatwild.com/images/gr_nutrition1.gif )
  • Tallow is a rendered (ie. cooked) form of beef or mutton fat, while suet is the non-rendered form (ie. straight from the animal carcass).  Tallow is often composed of 47% Oleic acid, 26% Palmitic acid, 14% Stearic acid, 3% Myristic, 3% Lineolic, 3% Palmitoleic fatty acids (ie. 50% saturated, 42% mono-unsaturated, and 4% poly-unsaturated).
Researchers found a dramatic drop in total fat for grass-fed pastured animals, as compared to grain-fed typical factory farm methods.

Note that mono-unsaturated fats lowers LDL cholesterol and raises HDL cholesterol.  The principal fats in red meat, bacon, and eggs are not saturated fats (ie. the fats that raise LDL cholesterol).  Red meat, bacon, and eggs are principally mono-unsaturated fats, the same fat that occurs in olive oil, which is almost universally considered one of the healthiest oils.  About 70% of the meat's fat will improve both LDL and HDL levels (if compared to the alternative of consuming carbohydrates such as potatoes, bread, or pasta).  The other 30% of the fat will raise both LDL and HDL, and therefore will have little effect on the ratio of HDL to total cholesterol (See p. 168 of Good Calories, Bad Calories).

Therefore, eating fatty meat (rather than a high carb meal of potatoes, bread, or pasta) would lower the risk of cardiovascular disease.  The same argument can be made for lard, bacon, chicken, and eggs.
  • Lard is pig fat, whether rendered or non-rendered.  Lard is 45% mono-unsaturated, 39% saturated, and 11% poly-unsaturated.  These fat ratios can be significantly shifted by what the pig has been fed.

  • Chicken fat from the #ChickenMafia is noted for being high in linoleic acid, omega-6 and omega-9 fatty acid.  Linoleic acid levels are between 17.9% and 22.8%.  These fat ratios can be significantly shifted by what the chicken has been fed.  Chicken factory feeding methods tend to minimize the healthy effects.  Small flock and pasture raised chickens tend to maximize the healthy effects.

    Cross Roads Farm reported the following:
    "A recent USDA-funded study between pasture-raised chickens and confinement chickens revealed the following: The pasture-raised chickens had 21% less total fat, 30% less saturated fat, and 28% fewer calories. The pastured chickens also had 50% more Vitamin A and a whopping 100% more Omega-3 fatty acids."
    From a culinary perspective, here are a few opinions from a chef and homemaker on the pragmatic differences between free-range chicken and the chicken factory variety.
In one study, scientists compared free-range pastured chicken that consumed just 5% DM (Dry Matter) from the pasture (ie. 95% DM grain-based chicken feed), to chicken raised in similar low intensity pens but without access to pasture (ie. 100% grain-fed chickens).  It is not surprising that there was no significant difference in the meats produced by these two groups when only a 5% dietary intake of pasture occurred.  Given the choice of high energy, palatable and satiating chicken feed, most animals would choose the easy road, as the chickens did in this case.
Other studies have found significant differences in the fats and nutritiousness of the meat between pasture raised chickens vs. chicken factory, high stress, high intensity lifestyles.
From the book Eating on the Wild Side, and its website, we learn:
  • One researcher found that when chickens are housed indoors and deprived of greens, their meat and eggs also become artificially low in omega-3s.  Eggs from pastured hens can contain as much as 10 times more omega-3s than eggs from factory hens.
Knowing these results, #EggMafia factory farms have resorted to supplementing their factory chicken feed with Omega-3 fatty acids at significant cost, which of course are passed on to consumers by the "Omega-3 egg" premium prices.  However, this doesn't even come close to the Omega-3 levels in eggs from pasture raised chickens, all occurring naturally.
In summary, it appears that small flock methodologies for pastured chicken are far superior to the mega chicken factory methods of the #ChickenMafia.

Omega-3 Enhanced Eggs

One health diet website responded to a question about the benefits from Omega-3 enhanced chicken eggs available at retail stores as follows:
"Recent studies suggest that in order for an egg to have an omega 6:omega 3 ratio close to the 2:1 that is thought to be favourable according to Paleolithic principles, the hen producing the egg would require a special feed beyond that of simply being free range. A 2009 study found that "omega-3 enriched eggs" contained an omega 6:omega 3 ratio of 2.27:1, whereas both "organic free range" and conventional eggs maintained a ratio of 10:1 (Samman et al. 2009).
Other studies have mentioned that the nutrient composition of the egg varies greatly with the feed given to the hen, and that consuming eggs modified to deliver higher amounts of omega-3 fatty acids "may lend a health advantage" (Shapira et al. 2010, p. 273)."

"Additionally, in response to your idea of absorption by the human body, I agree with the comment above that suggests the chicken does most of the processing. Ferrier et al. (1995) and Oh et al. (1991) both demonstrated that consumption of omega-3 fats from eggs were reflected in the blood profiles of humans - suggesting their easy assimilation. In fact, chickens are thought to be great 'factories' for making nutrients bio-available to humans (hence the wealth of literature suggesting all kinds of 'designer' eggs rich in antioxidants and such)."
 Others suggest that rather than buying Omega-3 enhanced eggs at significantly higher cost, it would be cheaper and just as healthy (or more healthy) to eat cheaper regular eggs (or better yet, more healthy pasture-raised eggs), plus sprinkle some flax seed on top of your regular diet.

Tomorrow, we will look at vegetable oils in our diets, as compared to animal fats.  Is canola oil superior to chicken fat?

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