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LipidsBiol 135 Lecture: IV. Structure, Function and Source of Macronutrients.

B. LipidsLipids are found everywhere in nature and are absolutely fundamental to good human health and nutrition. They constitute a diverse group of compounds which are related more by their physical properties rather than by their chemical properties. They function as energy storage, insulation and protection, fuel for metabolism and indispensable components of essential vitamins, hormones and regulators in the body.

In a Healthy, Balanced Whole Food Diet, there should never be a need to reduce your fat intake or cut back on any healthy lipids. The consumption of healthy lipids is vital to good nutrition and good health.

Whole Food Refined FoodUnrefined, entire original “item” Heavily processed from original form

All original nutrients remain intact Most (if not all) original nutrients removed

Unprocessed, not chemically treated Chemically treated (in processing & for shelf-life)

A really easy way to tell the difference between and “Bad Fat” and a “Good Fat” is to ask yourself where did it come from, directly, exactly, where? If it came from a “processing plant”, like margarine does, this should tip you off that regardless of what was originally used the product, it has become quite different after processing. Compare this to something that came directly from a healthy animal. And your choice is as easy as falling off a log! Note: If you have never tried walking on a log, you will find it is incredibly easy to fall off, it’s only natural really!

Many things about health are connected to using the common sense you have, a simple yet valuable method for determining the truth. In order to trust this method however, you must be active at protecting yourself from false information! The type of information gained from watching television, for example. This source of information will bombard you day and night with misleading information! Via television programs, advertising and news reports! There is no requirement for any program on television to be truthful – seriously, even the evening news is not obliged to tell you the truth! (Florida State vs. Fox News):

ORGANIC CONSUMER ASSOC, March 7, 2004. Title: “Florida Appeals Court Orders Akre-Wilson vs. Fox Television; Couple Warns Journalists of Danger to Free Speech, Whistle Blower Protection”. From a 1996 Investigative Report, litigation ensued. During appeal, FOX asserted that there are no written rules against distorting news in the media. They argued that, under the First Amendment, broadcasters have the right to lie or deliberately distort news reports on public airwaves. This was upheld.

There are many many other examples establishing that there is no requirement for telling the truth on television: This is a good time to understand that fact. Regardless of the person or institution or agency delivering the information, the issue is not the reputation or the power of the entity, the issue being able to distinguish lies from the truth! As some wise person once said: “Let truth be the authority and not authority be the truth”. The more informed you become the easier it will be for you to detect a lie and the faster you will be able to assess a situation for what it really is and make sound decisions.

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A perfect example of believing in authority to our own detriment is accepting the Big Fat Myth that still impacts our diet and health today - that cholesterol and saturated fats are bad for you. In addition, that poly-unsaturated vegetable oils should take the place of those naughty fats!

The trend to significantly reduce fats in our diet, especially saturated animal fats, took hold in the early 1960’s due to the studies by Dr. Ancel Keys that purported to find a causal link between diets high in animal fat and cardiovascular disease. This belief has never been shown to be true. In the “What is Nutrition” lecture notes, there is a re-visiting of that amazing study to show that even 50 years ago it should have been flagged for incredibly poor scientific methodology and for drawing farcical conclusions. For some time, real health mavericks have known that blaming animal fat consumption for our poor nutritional health was ridiculous and indeed removing beneficial saturated fats from our diets was significantly deleterious to human health. Now, over 50 years after the initial findings that were heavily promotion by all of the powerful health and medical groups, it is becoming more and more obvious that the information was not scientifically accurate. Still to this day, despite it being on the cover of Time Magazine that “Scientists Got it Wrong”, this mythos that fat causes heart disease continues to be an accepted lie. This lie is repeated in every textbook I’ve read about nutrition, including all the 2015 editions. Just one of the reasons to forgo a text for this class and write my own.

a)1961 b) 1984 c) 2014

Figure 1. Shows Time Magazine covers of: a) Dr. Ancel Keys in 1961, he claimed that saturated fats in the diet clogged arteries and caused heart disease; b) Perpetuation of the ‘Bad Cholesterol’ Myth in the 1980’s;and c) a published ‘correction’ of labeling “Fat the Enemy” in 2014.

Figure 2. Shows (left)the rates of butter and margarine consumption per capita per year, and (right) the number of deaths from diseases of the heart from the turn of the 20th century.

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As the graphs in Fig 2.indicate, the campaign to target animal fats (like butter), as bad for your health has been a success! In addition, there was and still is a force that has also encouraged American’s to replace butter with heavily processed margarines that contain hydrogenated vegetable oils. This has literally been the removal of something good and beneficial and replacing it with something toxic and deleterious. Please note the time frame of the graph on the right. At the same time that the consumption or butter and margarine were swapped out, the successful eradication of heart disease did not occur and has not occurred - even the American Heart Association has to show that the numbers for heart disease have gone up. In fact, Heart Disease is the number one killer of Americans. Number one! If the “Fat causes heart disease” myth were true, we would certainly not expect the numbers of people dying from heart disease to continue to rise. But wait, there’s more.

Since as a nation we have embarked on this low dietary fat crusade for over 50 years, if heart disease has continued to be a major health issue, then are we at least less fat? As a result of the reduction in the percentage and types of fats in our diet surely we are less fat as a result of eating less fat? No - Darn it! Americans are actually fatter because of it! How is that possible? It is possible by the simple fact that if you remove good fats from your diet and replace them with refined highly processed carbohydrates (like sugars and starchy grains), any excess carbohydrates will get converted almost immediately in your body to, you guessed it, FAT. So the truth of the matter is you can eat zero fat and still gain weight in fat.

Figure 3. As the graph shows, calories from fat have decrease by about 10%, but the prevelance of obesity has continued to increase. There is a notable incline in obesity during the mid 1980’s, after the introduciton of High Fructose Corn Syrup (HFCS) to many beverages and after the introduciton of Diet Sodas, containing artificial sweetenrs.

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In general, lipids are insoluble in water, meaning they do not dissolve in water, but typically will float on top of water since they are less dense. They are soluble in non-polar organic solvents (alcohol, ether, etc.). Lipids are essential dietary constituents because of their many important roles in the body, they provide high energy value and also they deliver fat soluble vitamins and are the building blocks for cell membranes, steroid hormones, etc. Lipids include fatty acids, triglycerides, phospholipids, sphingolipids, sterols, waxes, glycolipids and lipoproteins.

Overview of Lipids in Human Nutrition

1. Fatty Acids– these are made up of chains of carbon, for 2 to 24 Carbons long. The building blocks of lipids are Fatty acids and Glycerol

Saturated fats– have all the H atoms possible, i.e., there are no double bonds.

Unsaturated fats– do not have maximum H atoms, contain at least one double bond.

2. Glycerides– important energy storage molecule. Made from glycerol and fatty acids

a) Monoglyceride one fatty acid and glycerol.

b) Diglyceride two fatty acids and glycerol.

c) Triglyceride three fatty acids and glycerol.

3. Phospholipids – fundamental component t of all cell membranes. This is created by adding a polar phosphate containing fatty acid to a diglyceride.

4. Sterols –contain a4 fused carbon ring structure, most important example is Cholesterol.

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Fatty AcidsOne of the fundamental building blocks of nutritional lipids are fatty acids. They have the general formula CH3(CH2)n COOH where n can be any even number from 2 to 24.

The structure of a fatty acid includes the carboxylic acid group (COOH) on one end of a chain of carbon and hydrogen atoms, with a methyl group (CH3) of the other end. Fatty acids can be freely floating around but more commonly they are found bound in triglycerides and phospholipids.

There are two basic types of fatty acids: Saturated and Unsaturated. Saturated fatty acids do not have any double bonds, whereas unsaturated can have one (monounsaturated) or more than one (polyunsaturated) fatty acid.

Figure 1.Shows the structural differences between a saturated and unsaturated fatty acid. What is the configuration of the double bond in this unsaturated fatty acid? Answer: ___________.

Use the space below to draw out the saturated fatty acid Lauric Acid:

Use the space below to draw out the unsaturated fatty acid Linoleic acid:

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More details about Fatty AcidsThere are over 20 different fatty acids. They can vary by the length of the chain; whether carbons have double or single bonds between them; or by the total number of double bonds.

In a saturated fatty acid, almost all of the carbon atoms are bonded to hydrogen. A good example is lauric acid which has 12 carbons and is solid at room temperature.

Unsaturated fatty acids have one or more double bond between carbons, it is less saturated with hydrogen, and tends to be liquid at room temperature.

Monounsaturated fatty acids have one double bond. An example is Oleic acid which has 18 carbons (olive oil is an example).

Polyunsaturated fatty acids have more than one double bond and examples are the essential fatty acids linoleic acid(found in walnuts, almonds, brazil nuts, sesame seeds, sunflower, pumpkin or poppy seeds; also the following oils: walnut, wheat germ, blackcurrant seed, evening primrose and grape seed oils). Another example is alpha-linolenic acid (found in flaxseeds, flaxseed oil, pumpkin seeds and pumpkin seed oil, perilla seed oil, walnuts, and walnut oil).

Saturated and monounsaturated fats are more easily used by your body than polyunsaturated fats.

Figure 2.This flow chart shows the classification and organization of the different types of fatty acids in human nutrition and in the human body.

Fatty Acids may be classified by the number of carbon atoms as:Length of carbon chains:

Short-chain fatty acids (SCFAs): Less than eight carbons

Medium-chain fatty acids (MCFAs): Eight to 14 carbons

Long-chain fatty acids (LCFAs): 16 or more carbons

Very-long-chain fatty acids (VLCFAs): More than 22 carbons

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A fatty acid's chain length and saturation control its melting point. As chain length increases, melting point increases. Likewise, fats that are solid at room temperature (butter, coconut oil) have longer chain lengths than fats that are liquid at room temperature (fish oil, olive oil). With chain lengths being equal, unsaturated fats have lower melting points than saturated fats.

Saturated fatty acids are do not have any double bonds and may be represented by the general formula CH3(CH2)n COOH where n can be any even number from 2 to 24. The most common ones are:

Lauric acid CH3 (CH2)10 COOH (12 Cs) - found in coconut oil, breast milk.

Myristic acid CH3 (CH2)12 COOH (14Cs) - found in coconut, palm kernel oil, butter, cheese, whale blubber.

Palmitic acid CH3 (CH2)14 COOH (16 Cs) - found in poultry, beef, game meats.

Stearic acid CH3 (CH2)16 COOH (18 Cs) - found in cocoa butter, beef tallow, lard, butter, beef, pork, lamb.

Of the saturated fatty acids palmitic acid and stearic acid are the most widely distributed. Monounsaturated fatty acids contain one double bond. The most common dietary monounsaturated fatty acid is oleic acid which has the formula: CH3 (CH2)7 CH=CH (CH2)7

COOH.

The polyunsaturated fatty acids contain two or more double bonds. Linoleic acid, linolenic acid and arachidonic acid are important examples of polyunsaturated fatty acids, as they are essential fatty acids.

Essential Fatty Acids are unsaturated fatty acid that is essential to human health, but cannot be manufactured in the body, abbreviated EFA. There are three types of EFAs:

1. Arachnoidic Acid

2. Linoleic Acid*

3. Linolenic Acid

*When linoleic acid is obtained in the diet, it can be converted to both arachnoidic and linolenic acid.

Exercise: List the dietary sources of these three EFA’sEssential Fatty Acid Source in our DietArachnoidic Acid

Linoleic Acid

Linolenic Acid

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The Chemical Instability of Polyunsaturated Fatty Acids (PUFAs)Your tissues are made up mostly of saturated and monounsaturated fats, therefore your body requires more of them than polyunsaturated fats (which is true of all mammals). The main dietary Polyunsaturated Fatty Acids (PUFAs) are omega-3 and omega-6 fats. Although your body does need these, it needs them in relatively small quantities. One of the problems with PUFAs is that they are very chemically unstable, and highly susceptible to being altered and denatured by what's around them. Think about what happens to the oils in your pantry—they are susceptible to going rancid as a result of oxidation. In your body, PUFAs undergo a similar process when exposed to the toxic byproducts of proteins and sugars—especially fructose. This is why most fish oil supplements have such a short shelf life, and many are already oxidized before they hit the bottle. Consuming oxidized fats can do your body more harm than good.

When you eat too many PUFAs, they are increasingly incorporated into your cell membranes. Because these fats are unstable, your cells become fragile and prone to oxidation, which leads to all sorts of health problems, such as atherosclerosis. Now let's take a look at the most common PUFAs in your diet—the omega fats.

The Omega FatsOpposite the acid end is the "omega end" of a fatty acid (see figure below).

The location of the first double bond from the omega end dictates whether a fatty acid is an omega-3, omega-6, omega-9 (oleic acid), or another member of the "omega family."  Both omega-3s and omega-6s come in both short-and long-chain varieties.

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Omega-3 Fats Plant Based: The shorter-chain form of omega-3 is alpha-linolenic acid (ALA), the only

omega-3 found in plants (except for some algae). Foods rich in ALA include flaxseed oil (53 percent), canola oil (11 percent), English walnuts (9 percent), and soybean oil (7 percent). ALA is essential.

Animal Based: The longer-chain forms of omega-3 are found mostly in animals and they are eicosapentaenoic and docosahexaenoic acids (EPA and DHA) and are highly unsaturated, mainly found in fish, shellfish and krill. DHA is the primary structural component of your brain and retina, and EPA is its precursor. Your body can make some EPA and DHA from short-chain ALA, but does so inefficiently. Recent studies suggest less than one percent of ALA is converted, if you are consuming the typical Western diet. DHA is found in cod liver oil, fatty fish, and in smaller concentrations in the organs and fats of land animals.

Omega-6 Fats Shorter-chain: The shorter-chain form of omega-6 is linoleic acid (LA), which is the

most prevalent PUFA in the Western diet, is abundant in corn oil, sunflower oil, soybean oil and canola oil. All of the oils you should avoid.

Longer-chain: The longer-chain form of omega-6 is arachidonic acid (AA), which is an important constituent of cell membranes and a material your body uses to make substances that combat infection, regulate inflammation, promote blood clotting, and allow your cells to communicate. AA is found in liver, egg yolks, animal meats and seafood.

Traditionally, only two fats were considered "essential"—ALA (an omega-3 fat) and LA (an omega-6 fat). However, we now know it's the long-chain derivatives—arachidonic acid, DHA, and EPA—that your body needs the most. Although you have the enzymes to convert LA into these longer-chain fats (ALA, DHA and EPA), the conversion isn't efficient enough for optimal brain growth and development. This has led to a recent rethinking of what fats to consider "essential" and recommendations for adding more long-chain fats to your diet, to better meet these biological demands.

DHA and EPA: The "Anti-Inflammatory Fats"Scientific studies have uncovered a number of important health benefits from omega-3 fats, and it's looking more like it's DHA and EPA that are responsible for those benefits, rather than ALA. Science suggests that omega-3s offer the following benefits to your health:

Other Fatty Acid Configurations in the BodyThe combination of fats with carbohydrates and proteins make other molecules that have important functions. The main role of glycolipids and lipoproteins in the body is to act as “cell markers” for cell identification in the body.

Glycolipids are composed mostly of lipids with much smaller carbohydrates attached.

Lipoproteins are composed mostly of proteins with much smaller lipids attached.

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Important Fatty Acids in Human Nutrition

Figure 3.Shows the major important different fatty acids, highlighting the structural differences between saturated and unsaturated fatty acids. It also shows the structural differences between the nutritionally important omega-3, -6 and -9 fatty acids.

The term “Fats” and “Oils”When discussing fats and oils in the diet and in human nutrition, there are three (3) types of glycerides: Monoglycerides; Diglycerides, and Triglycerides. They are made by the two fundamental building blocks of lipids, the alcohol molecule glycerol, which creates the backbone for the attachment of one, two, or three fatty acids, respectively. The prefixes mono-, di-, and tri- are derived from Greek words meaning one, two, and three, and refer to the number of fatty acid.

Glycerides are important energy storage molecules. They are made from combining a glycerol molecule and one, two or three and fatty acids.

a) Monoglyceride = a glycerol molecule plus one fatty acid.

b) Diglyceride = a glycerol molecule plus two fatty acids.

c) Triglyceride = a glycerol molecule plus three fatty acids.

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TriglyceridesTriglycerides can also be called triacylglycerol, triacylglyceride (or TAG). These are the main constituent of animal fat and vegetable oil, and make up most of the fats digested by humans.

They are very important in that they allow the uptake and transport of fat-soluble vitamins. Plus, they play a role in metabolism. Any unused saturated or monounsaturated fatty acids are stored in adipocytes of adipose tissue by the body in the form of triglycerides. Fats occur chiefly in foodstuffs and in the fat deposits of most animals in the form of triglycerides. Triglycerides are esters of glycerol and fatty acids.

The Functions of Triglycerides in the Body

1 – Energy StorageAll lipids are good source of metabolic energy, that is because gram for gram, they have twice and much energy available than carbohydrates or proteins (9kcal/g compared to 4kcal/g respectively). The process required to utilize lipids as a fuel source is more complex than using carbohydrates as a source of metabolic energy.

2 – Insulation and ProtectionLipids do not conduct heat or electrical currents very well, therefore lipids are great insulators! Fat is stored in adipose tissue inside adipocytes (fat cells). Your fat cells in general do not increase or decrease in number, they either store more or less triglycerides. In the body the adipose under the skin is called the hypodermis or subcutaneous fat. It insulates the body from by preventing heat loss to the colder environment. The fat that surrounds internal organs is called visceral fat, and acts as a protective cushion from mechanical trauma.

3 – NutritionThe fat-soluble vitamins, A, D, E, and K all require lipids in the body to absorb them. These vitamins are transported through the body in vessels by chylomicrons. Vitamins E, D, and K are also stored in the fat tissue. Triglycerides help ensure adequate nutrition, because if there is too little dietary fat, or if a medical situation exists that interferes with the body’s ability to absorb lipids, then vitamin deficiency occurs.

What are Triglycerides made of?Triglycerides contain three fatty acid chains that are connected to a glycerol or glycerin “backbone” It is the most common lipid found in foods and in the human body. This is what people mean when they refer to “fats”.

Glycerol has three hydroxyl groups that are responsible for its solubility in water and its hygroscopic nature. Hygroscopy the property of absorbing moisture from the air. An example of a hygroscopic food is honey; this property is what makes honey have a long shelf life because it can pull moisture out of the air.

The glycerol backbone is central to all lipids known as triglycerides. Glycerol is sweet-tasting and generally considered non-toxic.

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It is a colorless, odorless, syrupy, sweet liquid, C3H8O3, usually obtained by the saponification of natural fats and oils. It is often used for sweetening and preserving foods. It is also used in the manufacture of cosmetics, perfumes, inks, and certain glues and cements, as a solvent and automobile antifreeze, and in medicine in suppositories and skin emollients.

Figure 4.How to make a triglyceride: You need one glycerol (glycerin) molecule as the backbone for the attachment of three (3) separate fatty acids.

The 3 Fatty Acids in one Triglyceride are usually all Saturated or UnsaturatedAs we have seen, fatty acids vary with respect to their size, and the number and position of the double bonds found in the molecule.

In general, when speaking of “a saturated fat” this refers to a triglyceride that consists fatty acids containing only saturated fatty acids! Remember that saturated fatty acids have no double bonds between the individual carbon atoms of the fatty acid chain. That is, the chain of carbon atoms is fully "saturated" with hydrogen atoms. The same is usually also true for “an unsaturated fat”, this refers to a triglyceride that has 3 fatty acid chains that are all unsaturated!

Triglycerides that are solid at room temperature are referred to as fats, and are usually saturated.

Triglycerides that are liquid at room temperature are called oils, and are generally more unsaturated than the solid fats.

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Figure 5.The chemical reactions that make mono-, di- and triglycerides: The hydroxyl (OH) or alcohol group of the glycerol is the portion that reacts with the carboxylic (COOH) end of the fatty acid. By removing one water molecule (H2O) for each fatty acid attached, a mono-, di- and triglyceride is made by dehydration synthesis reactions.

Quick Basic Review of How Atoms form Chemical Bonds:

As seen in the section regarding carbohydrates, the Carbon atom has 6 protons, 6 electrons and most commonly 6 neutrons. Carbon (C) has 4 outer shell or valence electrons. Thus, it can make 4 covalent bonds, giving it versatile qualities. The general term monomer is used to describe the smallest type, or building blocks, of these organic molecules. The general term polymer describes the larger, more complex molecules.

The three types of organic molecules in the diet, carbohydrates, lipids and proteins, all have building blocks called monomers (mono- meaning one). These are the simplest structure that they can be broken down to.

These organic molecules can also have very complex forms, and these are called polymers (poly- meaning many). These are the more complex structures that are made by many units of the building blocks. If we ingest complex polymers, our bodies need to break them down into monomers so they are small enough to be absorbed and then they can be used by the body to make complex polymers again!

There is a pattern to how the body builds organic molecules, and the type of chemical reaction is called dehydration synthesis (or condensation) reactions. The opposite of this is the breakdown of complicated molecules by the type of chemical reaction is called hydrolysis reactions. This involves breaking chemical bonds with water (hydro = water; lysis = break)

In the Figure 5above it can be seen that a free fatty acid can make a covalent bond with one of the 3 hydroxyl groups (OH) coming from the carbon back bone of glycerol. In fact, by ‘removing’ a water molecule from the two molecules that are about to combine, they thereby make a larger, more complex molecule (hence the name dehydration synthesis).

Overview of Chemical Reactions in the Body

Chemical Reactions in the body are used to Store, Release, or Transfer Energy.

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Metabolism - Sum total of all chemical reactions in body.

Metabolism = Anabolism (reactions that build up) + Catabolism (reactions that break down)

1) Endergonic Reactions – Require Energy (E) inpute.g. A + B + E → C (Anabolic Reactions)

A specific example: The formation of a monoglyceride from 1 glycerol and 1 fatty acid.

The removal of water (H2O) to create a larger molecule is called a Dehydration Synthesis reaction.

Overall, these can be referred to as Anabolic Reactions – they are synthesizing something, building a more complex, larger molecule from simpler, smaller molecules and they require input of E.

2) Exergonic Reactions – Release Energy (E)e.g. C → A + B + E (Catabolic Reactions)

A specific example: The breakdown of a monoglyceride into 1 glycerol and 1 fatty acid.

Often in biological systems water (H2O) is used to break chemical bonds, this is called Hydrolysis.

Overall, these can be referred to as Catabolic Reactions – they are breaking chemical bonds. Large molecules are broken down to produce smaller molecules and they release E that can be used for physiological work.

Fats= Energy Storage in the BodyFatty acids are the most important energy storage molecule in the body – no doubt about that. As we are all likely to know the most common form of energy storage in the body are triglycerides, and they are stored in adipocytes (fat cells) as energy reserves for a rainy day. The lipid droplet is in the fat vacuole in the center of the cell, usually taking up most of the cytoplasm of the adipocyte! Adipocytes are not stagnant, inert cells in the body – on the contrary, they are active and dynamic and respond to a wide range of important signal molecules in the body.

Phospholipids

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After the triglycerides, the next largest lipid component in the body is phospholipid. A great variety of phospholipids are present in the body and have an enormous role in creating important cellular organelles.

Phospholipids are fat derivatives but unlike most lipids, a portion of them is soluble in water. This is because they are created by taking a triglyceride and replacing only one of the three fatty acids with a phosphate and nitrogen containing.

Figure 6.Shows the arrangement of a phospholipid, with its polar head (hydrophilic) and non-polar tails (hydrophobic). This characteristic makes it an ideal molecule to help create the plasma membrane of living cells. Phospholipids form a bilayer and thereby create a semipermeable barrier.

The phospholipids still have the glycerol backbone but with two fatty acids and a phosphorus group attached. The hydrocarbon chains (tails) remain hydrophobic. However, the charges on the phosphorus and nitrogenous containing head results in that portion of the molecule becoming hydrophilic. As a consequence, phospholipids are amphiphilic (or amphipathic) – that is they can accommodate both polar (hydrophilic ‘water loving’) and non-polar (hydrophobic ‘water fearing’) environments. This characteristic makes it an ideal molecule to help create the plasma membrane of living cells.

Figure 7.The Lipid Bilayer of the plasma membrane is created by the arrangement of phospholipids as shown above. All cell membranes also contain cholesterol; the typical lipid content of cells is about 50%. Reminder, the terms listed below next to each other are all the same kinds of terms:Hydrophilic, polar, attracts water.Hydrophobic non polar, repels water.

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Phosphatidyl esters (phosphoglycerides) are an important class of phospholipids. They are found predominantly in animal tissues as a structural component of cell walls and mitochondria. In the blood, as a component of lipoproteins, phospholipids serve in the transport of fat between tissues. Only a very small amount of phospholipid is present in fat stores. The phospholipids contain phosphate, which can be used as a high energy compound, for example in ATP.

The cell membranes of every cell in the body are made of a phospholipid bilayer. The major part of the phospholipid in the cell membrane is lecithin which is used as an emulsifier in foods such as salad dressings which keeps oils and water mixed together; otherwise you would have two separate substances with two different flavors.

LecithinsLecithin - its name is derived from lekithos an Ancient Greek term for "egg yolk", as it was originally isolated from egg yolk. Lecithin is a term used to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues composed of phosphoric acid, choline, fatty acids, glycerol, glycolipids, triglycerides, and phospholipids (e.g., phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol).

Also available from sources such as soybeans, milk, marine sources, rapeseed(a hybrid of this is canola oil), cottonseed, and sunflower. Note: Soybean, canola and cotton seed oils have high levels of toxic substances found in them naturally, for example Erucic Acid, Hemagglutinin and Glycosides). More about these toxic substances later.

Lecithin has low solubility in water, but is an excellent emulsifier. In fact if you are an avid reader of food labels you will often see the terms “soy lecithin as an emulsifier” at the very end of a food product. Lecithin is sold as a food supplement and for medical uses. In cooking, it is sometimes used as an emulsifier and to prevent sticking, for example in nonstick cooking spray. Caution: If it is derived from soy, then most lecithin (about 90%) will come from Genetically Modified (GM) crops if not identified as ‘organic’.In aqueous solution, its phospholipids can form either liposomes, bilayer sheets, micelles, or lamellar structures, depending on hydration and temperature. This results in a type of surfactant that usually is classified as amphipathic or amphiphilic – soluble in both water and fat. Liposomes have an inner polar layer that water soluble molecules would prefer, whereas the inner core of micelles are composed of the non-polar lipid tails of and lipid-soluble molecules would prefer this environment. See figure to the right for comparisons.

SphingolipidsThe name ‘sphingolipids’ comes from the sphinx in Greek mythology, part woman and part lion – they devoured all who could not answer their riddles. Next to phospholipids, sphingolipids are a second type of lipid found in cell membranes, particularly nerve cells and brain tissues. They do not contain glycerol, but retain the two alcohols with the middle position occupied by an amine.

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The sphingolipids are a class of lipids in which the glycerol is replaced by sphingosine or its derivative. Sphingosine is both an alcohol, and a nitrogen containing base: CH3(CH2)12. CH=CH.CH(OH). CH(NH2). CH2OH

There are three classes of sphingolipids:1) Sphingomyelin2) Cerebrosides3) Gangliosides

Sphingomyelin is an important constituent of the myelin sheath of nerves. It is present in most animal cell membranes. Sphingomyelin contains the base sphingosine, linked through a phosphate molecule to choline. Cerebrosides, contain one or more sugar units and a fatty acid is joined to the amino radical of the base, these are widely distributed in nervous tissues. Gangliosides have a polar head group with sugars and are found in neural tissue membranes.

Importance in Human HealthThe human brain and spinal cord is made up of gray matter and white matter. The gray matter is composed mostly of nerve cell bodies (i.e. the soma of neurons). The white matter is made of nerve axons wrapped in a white lipid coating, the myelin sheath, which provides insulation to allow rapid conduction of electrical signals. Multiple sclerosis caused by a gradual degradation of the myelin sheath. Significance of Aspartame and MS-Like symptoms.

Sphingolipids in obesity, type 2 diabetes, and metabolic disease (2013).Sphingolipids, a lipid class with both signaling and structural properties, have recently emerged as key players in most major tissues affected by diabetes and are required components in the molecular etiology of this disease, shown to mediate loss of insulin sensitivity, to promote the characteristic diabetic pro-inflammatory state, and to induce cell death and dysfunction in important organs such as the pancreas and heart. Furthermore, plasma sphingolipid levels are emerging as potential biomarkers for the decompensation of insulin resistance to type 2 diabetes.

The above information is alluding to the connection between significant increases in refined sugar intake, which leads to inflammation, which leads to diabetes and heart disease.

SterolsSterols are alcohols containing the steroid structure of four fused carbon rings. This type of lipid has 17 of its C atoms arranged in 4 rings (see figure).

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The most abundant steroid in human body is Cholesterol and it is the most important sterol that relevant to human health. It is present in all animal tissues but not in plants. Egg yolk, dairy products, shellfish and meats contain fairly large amounts of cholesterol.

Cholesterol is Very Important!Although all mammals can make cholesterol and therefore it is not an essential nutrient, it is still extremely important to have sufficient and adequate amounts of cholesterol in your body. Cholesterol is not bad for you. This is a harmful myth that is not based in scientific facts. Considering that all animals are capable of synthesizing cholesterol, it must have some very vital and useful role in physiological systems.

The most Complex of the LipidsThe sterols (again cholesterol is the most important example in the human body) are the most complex of the lipid molecules and its role in the body is matched by its complex chemical structure. You would never want to have too little cholesterol, in fact, your body can not function properly, nor would you continue to live without any cholesterol in your body. To deliberately lower your cholesterol levels to values that have been arbitrarily determined is not a sound healthy practice!

Steroids that are derived directly from Cholesterol

1. Sex hormones a. Testosteroneb. Estrogen c. Progesterone

2. Cortisol3. Bile Salts4. Vitamin D

Estrogen, androgens, progesterone, and most of the adrenocortical hormones (from the adrenal gland) are derived from cholesterol. Ergosterol is one of a group of sterols found in many yeasts and fungi. ADD MORE

The bile salts (sodium glycocholate and sodium taurocholate) are formed by the combination of the amino acids glycine and taurine with cholic acid which is a derivative of cholesterol. The bile salts play an essential role in emulsification, digestion and absorption of dietary fats.

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Figure 8.The most important of the sterols is cholesterol because it is the basis from which many other significant steroid molecules are created. They have a very wide variety of influential roles in the body.

Vitamin D Under the influence of ultraviolet light, it is converted into vitamin D as is 7-dehydrocholesterol which is the natural precursor of vitamin D in animal tissues. Rather than cholesterol, plants contain a sterol compound known as phytosterol (plant sterol).Several different phytosterols occur naturally in plant foods and plant-derived oils.

WaxesWaxes are fatty acid esters of higher alcohols. They occur widely in the cuticle of leaves and fruit and in the secretions of insects. Waxes are not an important constituent of any of the higher land animals nor do they contribute extensively to normal human diets – except bee’s wax because it is way neat.

Functions of Lipids in the Human BodyDietary fat is the most concentrated source of energy, supplying 9 kcal/g, (37kJ/g). This is compared to 4kcal/g, for both carbohydrates and protein, that is, fats provide more than twice the caloric energy as carbohydrates or proteins gram for gram. This demonstrated that they are a great way to store a rich source of energy. Like carbohydrate, dietary fat is protein sparing and glucose sparing.

The Importance of Fats in FoodsA) Taste: Fats lend palatability to food as many of the substances responsible for the flavor and aroma of food are fat-soluble and are associated with fat in the diet. Dietary fat acts as the source of fat-soluble vitamins and the essential fatty acids.

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B) Nutrition: As we recall, there are essential fatty acids (EFA’s), please not there is no such thing as an essential carb! In the body, EFA’s are required for growth, reproduction, skin integrity, utilization of body fat and maintenance of cell membranes. They are also precursors of prostaglandins and a number of other compounds including thromboxanes, endoperoxides and leukotrienes.

C) Energy Storage: Stored fat in the form of adipose tissue insulates and protects internal organs while serving as a reserve source of energy. Fats are important as structural components of cell and mitochondrial membranes as well as being constituents of specific membrane receptor sites.

DIGESTION, ABSORPTION, AND TRANSPORT OF LIPIDS

Each day, the GI tract receives, on average from the food we eat, 50 to 100 grams of triglycerides, 4 to 8 grams of phospholipids, and 200 to 350 milligrams of cholesterol. The body uses various strategies to digest and absorb the lipids that we eat. Fats are hydrophobic-that is, they tend to separate from the watery fluids of the GI tract-whereas the enzymes for digesting fats are hydrophilic. The challenge is keeping the fats mixed in the watery fluids of the GI tract.

LIPID DIGESTIONThe goal of fat digestion is to dismantle triglycerides into small molecules that the body can absorb and use-namely, monoglycerides, fatty acids, and glycerol.

In the Mouth Fat digestion starts off slowly in the mouth, with some hard fats beginning to melt when they reach body temperature. The moth starts the process of mechanical digestion by chewing and getting the item into solution. A salivary gland at the base of the tongue releases an enzyme, lingual lipase, that plays a minor role in fat digestion in adults and an active role in infants. In infants, this enzyme efficiently digests the short-and medium-chain fatty acids found in milk.

In the StomachIn a quiet stomach, fat would float as a layer above the other components of swallowed food. The stomach is unique in that it is the only organ of the GI tract that has three (3) muscles layers. The strong muscle contractions generated by this special arrangement effective mixes the contents and propels them toward the pyloric sphincter. Some chyme passes through the pyloric sphincter periodically, but the remaining partially digested food is propelled back into the body of the stomach. This churning grinds the solid pieces to finer particles, mixes the chyme, and disperses the fat into smaller droplets – this is a form of mechanical digestion, as no chemical bonds have been broken yet. These actions help to create a greater surface area in which the fat can be exposed to the gastric lipase enzyme – and have a greater effect. This enzyme performs best in the acidic environment of the stomach. Still, little fat digestion takes place in the stomach; most of the action occurs in the small intestine.

In the Small IntestineWhen fat enters the small intestine, it triggers the release of the hormone cholecystokinin (CCK), which signals the gallbladder to release its stores of bile. Remember that the liver makes bile, and the gallbladder stores it until it is needed. Among bile's many ingredients are

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bile acids, which are made in the liver from cholesterol and have a similar structure. In addition, they often pair up with an amino acid (a building block of protein). The amino acid end is attracted to water, and the sterol end is attracted to fat. This structure improves bile's ability to act as an emulsifier, drawing fat molecules into the surrounding watery fluids. There, the fats are fully digested as they encounter lipase enzymes from the pancreas and small intestine. Most of the hydrolysis of triglycerides occurs in the small intestine. The major fat-digesting enzymes are pancreatic lipases; some intestinal lipases are also active.

Dismantling the TriglycerideThese hydrolysis enzymes remove one, then the other, of each triglyceride's outer fatty acids, leaving a monoglyceride. Occasionally, enzymes remove all three fatty acids, leaving a free molecule of glycerol.

Dismantling the PhospholipidsPhospholipids are digested similarly-that is, their fatty acids are removed by hydrolysis. The two fatty acids and the remaining phospholipids fragment are then absorbed.

* Most sterols can be absorbed as is; if any fatty acids are attached, they are first hydrolyzed off.

Bile's RoutesAfter bile enters the small intestine and emulsifies fat, it has two possible destinations. Most of the bile is reabsorbed from the intestine and recycled. The other possibility is that some of the bile can be trapped by dietary fibers in the large intestine and carried out of the body with the feces. Because cholesterol is needed to make bile, the excretion of bile effectively reduces blood cholesterol.

A Natural Way to Reduce Excess CholesterolIf a person wanted to lower their blood plasma levels of cholesterol without using dangerous drugs, then eating sufficient dietary fibers is the most effective at lowering blood cholesterol, particularly the water soluble fibers commonly found in fruits, whole grains, and legumes. In fact, studies have shown that the fibers in oats, bran and apple are particularly good at ‘grabbing’ cholesterol and pulling it out of the body.

LIPID ABSORPTION – Size is ImportantSmall molecules of digested triglycerides (glycerol and short-and medium-chain fatty acids) can diffuse easily into the intestinal cells; they are absorbed directly into the bloodstream. Larger molecules (the monoglycerides and long-chain fatty acids) merge into spherical complexes, known as micelles.

Micelles are emulsified fat droplets formed by molecules of bile surrounding monoglycerides and fatty acids. This configuration permits solubility in the watery digestive fluids and transportation to the intestinal cells. Upon arrival, the lipid contents of the micelles diffuse into the intestinal cells. Once inside, the monoglycerides and long-chain fatty acids are reassembled into new triglycerides. Within the intestinal cells, the newly made triglycerides and other lipids (cholesterol and phospholipids) are packed with protein into transport vehicles known as chylomicrons. The intestinal cells then release the chylomicrons into the lymphatic system. The chylomicrons glide through the lymph until they reach a point of entry into the bloodstream at the thoracic duct near the heart.

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The blood carries these lipids to the rest of the body for immediate use or storage. An examination of these lipids in the body (e.g. via blood work) can reveal the kinds of fat that the diet has been delivering. The fat stores and muscle cells of people who eat a diet rich in unsaturated fats, for example, contain more unsaturated fats than those of people who select a diet high in saturated fats. This not a judgment call; it must be remembered that saturated fats are not bad for you, despite what you have probably heard for your entire life.

LIPID TRANSPORT– There are 4 basic carriers of hydrophobic lipid in the plasma.

Figure 9.The liver is a busy organ involved in many important tasks. A critical one is the receiving, processing, storing and packaging of lipids for transport.

How are Lipids Transported in the Body?The blood that is circulating within your blood vessels has 2 main components:

1) Plasma = the fluid portion of blood. About 55% of total blood volume

2) Cellular or formed elements = the cells of blood (RBC’s + WBC’s). About 45% of blood.

An important realization is that plasma is mostly water! It has many substances dissolved in it (like oxygen, glucose, electrolytes, vitamins, etc.) but it is 92% water. This means that any lipid which is not water soluble will have a difficult time getting around the body in the blood stream. This challenge is solved by what are called lipoproteins, these are molecules comprised of lipids

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and protein in such a way that the lipoproteins act as transporters for lipids in the blood. You can visualize them as various “speed boats” that can whiz the different types of lipids to where they need to go in the body.

*Lipoproteins with a low protein-to-lipid ratio have a low density; those with a high protein-to-lipid ratio have a high density.

Lipoproteins in the Body – there are 4 Types1. Chylomicrons These are the largest and least dense of the lipoproteins - a cluster of lipids and proteins that are used as transport vehicles for fats.

Chylomicrons transport diet derived lipids (triglycerides) from the small intestine, through the lymphatic vessels and in to the blood stream and the rest of the body. As chylomicrons pass through bloodstream, body cells remove lipids from them. The liver cells remove the remnants of the chylomicrons from the blood and reassembles them into new triglycerides.

The liver is the most active site of lipid synthesis; it uses fatty acids to make cholesterol, other fatty acids, triglycerides from carbohydrate, protein and alcohol. The new lipids are combined with a protein carrier and are transported to other parts of the body

2. VLDL: Very Low Density Lipoprotein (VLDL) are made in the liver and transport mainly triglyceride (about 50%), some cholesterol, and phospholipid. The VLDL travel through the body and cells remove triglyceride from them. As they lose triglyceride, the proportion of cholesterol increases and they become more dense; they become a low-density lipoprotein (LDL)

3. LDL: Low Density Lipoprotein (LDL) are composed primarily of cholesterol (about 50%). They circulate throughout the body and release triglyceride, cholesterol and phospholipid to body cells. The body cells collect the lipids and use them to make cell membranes, hormones or store them for later use. The liver removes LDL from circulation. The LDL is not good or bad, it is a Carrier of Cholesterol and other lipids.

4. HDL: High Density Lipoprotein (HDL) transports cholesterol from the cells back to the liver for recycling or disposal. This is where the role of HDL in picking up ‘excess cholesterol’ has become the focus of its role and the declaration of it as the “good cholesterol”. Please realize that HDL is not cholesterol it is a Carrier of Cholesterol.

Just to be clear: There is NO EVIDENCE that Fats cause Heart Disease

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Because heart disease often begins with a buildup of fatty plaques in arteries, that is perhaps the reason this topic is always presented right after a discussion of lipids in the body. Lipids do not cause heart disease; it appears that lipids, calcium and other elements are erroneously deposited in vessels wall as walls as a consequence of chronic inflammation. In other words, the body is already out of balance and it may be that the body is in ‘emergency mode’ and lipids are attempting to assist in protecting the body, but there are so many confounding variables that the body continues to become more unbalanced.

Chronic high blood pressure can begin to injure the lining of arteries. This may in turn attract macrophages which can incorporate calcium into the lipids and thereby harden the fatty deposits. It is estimated diets high in refined carbohydrates, like sugar (sucrose), high fructose corn syrup (HFCS) and starchy grains help to create a state of inflammation in the body. Drinking alcohol contributes to this state of emergency in your body! As does smoking conventional and e-cigarettes that contain longs lists of known carcinogens. The general lack of regular physical exercise also impacts the blood glucose and lipid levels in the blood stream.

Arteriosclerosis is a general hardening of a blood vessel wall.

Atherosclerosis is a type of arteriosclerosis that involves a narrowing of arteries due to buildup of a lipid containing plaque in the walls of the blood vessel. The plaque contains hardened calcified lipid debris with cholesterol, platelets, calcium, and cellular waste products.

You blood vessels being in this disease state will greatly increases the chance of blood clots occurring and causing a blockage of the blood vessel. If this blood vessel supplies the heart, this can lead to a heart attack, or if it supplies the brain, it can cause a stroke. A good positive move to counter balance these potentially harmful pathways is to load up on foods rich in antioxidants and phytochemicals. It is also important to get plenty of exercise and.

Statins - Drugs to Lower CholesterolThe use of drugs that lower cholesterol, like Stains, are based on the premise that elevated cholesterol and that alone is the cause of heart disease. There is actually no scientific evidence for this belief. Cholesterol is found in lipid deposits called “plaques” in diseased artery walls, yes, but that does not mean that cholesterol has caused this to happen! In fact, the more recent and sound scientific exploration of the cause of cardiovascular disease is that it is started by chronic inflammation. A precursor to this state is chronically elevated blood glucose levels – this is why diabetes type 2 and heart disease are linked.

Additional Nutritional Information about LipidsSaturated Fat is Not Associated with Increased Heart Disease RiskPlease do not confuse the hazards of Trans Fats with saturated fats! This outdated and deliberately misleading hypothesis that saturated animal fats and tropical oils are bad for your health is now revealed!

Trans fats are now officially recognized, government health agencies and the medical establishment as a whole are still holding on to Nothing could be further from the truth, and if you care about your health you’d be wise to reconsider the advice to follow a strict low-fat diet.

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Mounting scientific evidence supports saturated fat as a necessary part of a heart healthy diet, and firmly debunks the myth that saturated fat promotes heart disease. For example:

o Dr. William Castelli stated in 1992 (Archives of Internal Medicine):"In Framingham, (Heart study), the more saturated fat one ate, the more cholesterol one ate, the more calories one ate, the lower the person’s serum cholesterol. The opposite of what… Keys et al would predict…We found that the people who ate the most cholesterol, ate the most saturated fat, ate the most calories, weighed the least and were the most physically active."

A 2010 meta-analysis, which pooled data from 21 studies and included nearly 348,000 adults, found no difference in the risks of heart disease and stroke between people with the lowest and highest intakes of saturated fat.

Another 2010 study (Am J Clin Nutr) found that a reduction in saturated fat intake must be evaluated in the context of replacement by other macronutrients, such as carbohydrates. When you replace saturated fat with a higher carbohydrate intake, particularly refined carbohydrate, you exacerbate insulin resistance and obesity, increase triglycerides and small LDL particles, and reduce beneficial HDL cholesterol. The authors state that dietary efforts to improve your cardiovascular disease risk should primarily emphasize the limitation of refined carbohydrate intake, and weight reduction.

What is Hydrogenated Oil?In America soybean oil accounts for approximately 65% of the oils that people eat annually. About half of it is hydrogenated, because soybean oil is too unstable to be used in food manufacturing otherwise. Partially hydrogenating oils also prolongs shelf life. Raw butter, for example, is likely to go rancid far quicker than margarine.

The process of hydrogenating vegetable oils involves forcing hydrogen gas into the oil at high temperature and high pressure, creating a more saturated fat that is solid at room temperature. It also involves all sorts of other chemical processes (see Margarine vs. Butter article).

There are “partially” and “fully” hydrogenated oils and they are different: Partially hydrogenated oil contains trans fat. Nearly half of the fat content in margarine is trans fat. Whereas fully hydrogenating an oil takes the hydrogenation process “all the way” and transforms the fat from trans into saturated fatty acids. As we will see, fully hydrogenated soybean oil is still not a healthy choice.

The Health Hazards of Trans Fats Found in Partially Hydrogenated OilIn the late 1990’s, researchers began realizing that these chemical alterations actually had adverse health effects and this has been scientifically verified. The completely unnatural man-made fats created through the partial hydrogenation process cause dysfunction and chaos on a cellular level, and studies have linked trans-fats to:

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Cancer, by interfering with enzymes your body uses to fight cancer

Chronic health problems such as obesity, asthma, auto-immune disease, cancer, and bone degeneration

Diabetes, by interfering with the insulin receptors in your cell membranes

Heart disease, by clogging your arteries (study with women having underlying coronary heart disease, eating trans-fats increased the risk of sudden cardiac arrest three-fold!)

Decreased immune function, by reducing your immune response

Increase blood levels of low density lipoprotein (LDL), while lowering levels of high density lipoprotein (HDL)

Reproductive problems by interfering with enzymes needed to produce sex hormones

Interfering with your body’s use of beneficial omega-3 fats

Soon after the FDA required food manufacturers to list trans fat content on the label — which took effect on January 1, 2006 — the industry began searching for viable alternatives to appeal to consumers who increasingly began looking for the “No Trans Fat” designation. It didn’t take long before Monsanto had tinkered forth a genetically engineered soybean that is low in linolenic acid, to present to the public as a healthy alternative.

What Makes for a Heart Fat Healthy Diet?It’s important to realize that saturated fats from animal and vegetable sources provide a number of important health benefits, and your body requires them for the proper function of your:

Cell membranes Bones (to assimilate calcium) HeartLiver Genetic regulation HormonesImmune system Satiety (reducing hunger) Lungs

To prevent heart disease it’s critical to address your insulin- and leptin resistance, which is the result of eating a diet too high in sugars and grains, not fat.

As decades of research has shown, dietary fat has very little to do with your heart disease risk—with the exception of trans fats from partially hydrogenated vegetable oils, which have been linked to increased heart disease risk, even in small amounts. So, to safely and effectively reverse insulin and leptin resistance, thereby lowering your heart disease risk, you need to:

1. Avoid Sugar, fructose, grains, and processed foods 2. Eat a healthy diet of whole foods, ideally organic, and replace refined carb grain with:

o Large amounts of vegetables o Low-to-moderate amount of high quality protein (organically raised, pastured

animals) o As much highly quality healthy fat as you want (saturated and monosaturated from

animal and tropical oil sources). Most people actually need upwards of 50-70

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percent fats in their diet for optimal health - way less than the 10% currently recommended.

One of the most important fats your body needs for optimal health is animal-based omega-3. Deficiency in this essential fat can cause or contribute to very serious health problems, both mental and physical, and may be a significant underlying factor of up to 96,000 premature deaths each year. Besides animal-based omega-3 fats, other sources of healthful fats to add to your diet include:

Avocados Butter made from raw grass-fed organic milk

Raw dairy Organic pasturedegg yolks

Coconuts andcoconut oil

Unheated organicnut oils

Raw almonds, pecans, macadamia, and seeds

Grass-fed meats

Healthy Fat Tips to Live ByThe most effective prevention strategy against heart disease you’ll likely ever find is your diet—the foods you do and do not eat every day. For example, a Mediterranean-style diet has been shown to be three times more effective than statin drugs at reducing cardiovascular mortality. A Mediterranean-style diet is basically a whole-food diet. And that is indeed key for any healthy diet.  The answer to your heart disease concerns is to EAT REAL FOOD. This change alone will dramatically reduce the amount of refined sugar and processed fructose in your diet. It will also address the issue of healthful versus harmful fats in your diet. Besides eliminating processed foods, the following tips can help ensure you’re eating the right fats for your health:

Use organic butter made from raw grass-fed milk instead of margarines and vegetable oil spreads.

Use coconut oil for cooking. It is far superior to any other cooking oil and is loaded with health benefits.

Use olive oil COLD, drizzled over salad or fish, for example. It is not an ideal cooking oil as it is easily damaged by heat.

Following my nutrition plan will teach you to focus on healthy whole foods instead of processed junk food.

To round out your healthy fat intake, be sure to eat raw fats, such as those from avocados, raw dairy products, and olive oil, and also take a high-quality source of animal-based omega-3 fat, such as krill oil.

What Fats Are and Why You Need Them in your FoodLipids: category of compounds containing carbon, hydrogen, and oxygen that are hydrophobic (insoluble in water). Fat is the common name for just one type of lipid, known as a triglyceride. Fats serve multiple functions in foods including giving a flaky texture to baked goods; fats make meats tender; they provide flavor and aromas; and they contribute to satiety.

Fats and other lipids perform important functions in the body including energy storage, insulation from cold temperatures, transport of proteins in blood, and they form cell membrane structures. The three types of lipids found in foods and in your body include triglycerides (fats), phospholipids, and sterols. The basic unit of triglycerides and phospholipids are fatty acids.

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The following each provide 3.5-4.5g of linoleic acid, daily intake.2 teaspoons walnut oil or wheat germ oil;10-15g of walnuts, brazil nuts, sesame, sunflower, pumpkin or poppy seeds;20-30g of almonds;5.8g (5,800mg) blackcurrant seed oil supplement (gamma linolenic acid (GLA) content);4.5g (4,500mg) evening primrose oil supplement (gamma linolenic acid (GLA) content);5.3g (5,300mg) grape seed oil supplement.

Saturated and unsaturated fatty acids help to shape foods for example the solid stick of butter or the liquid vegetable oil.

How does your body use fat and cholesterol?Fat is an energy-dense source of fuel containing 9kcal/g. Glucagon also stimulates release of fat from fat cells to fuel heart, liver, and muscle. It is needed for absorption of fat-soluble vitamins A, D, E, K, and carotenoids.

It also insulates your body to maintain body temperature and cushions bones, organs, nerves. Two polyunsaturated fatty acids, linoleic acid (an omega-3 fatty acid) and alpha-linolenic acid (an omega-6 fatty acid), are essential eicosanoids, the hormone-like substances involved in inflammation, blood clotting, blood pressure.

The essential fatty acids help maintain healthy skin cells, nerves, and cell membranes while eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the two omega-3 fatty acids that are heart healthy (lowers one's risk of coronary heart disease). Cholesterol plays several vital roles in the body including being part of cell membranes, serving as a precursor for Vitamin D, Bile, Sex Hormones, Cortisol and essential fatty acids. The desired ratio for omega-6 to omega-3 oils is 4:1. Most Americans who eat the Standard American Diet (SAD) have a ratio that is 20:1, since many processed foods are loaded with vegetable oils (soy, canola, corn) that contain a lot of omega-6 oils. Remember, these oils are also highly processed and therefore much of their original nutrients are gone. Therefore it is important for most to get more high quality omega-3’s in the diet and taper off on the poor quality omega-6’s.

Where is the Saturated Fat in your Foods?In terms of where to find the beneficial saturated fats in your diet – mostly in whole dairy products like milk, butter and cheese, red meats, tropical oils, such as coconut oil. In regard to the composition of various fats, it is most common for food products to contain a combination of saturated, monounsaturated, and polyunsaturated fat.

The Problems of Nutrition in World: Mercury and FishMethyl-mercury is a toxic chemical especially harmful to the nervous systems of unborn children. It accumulates in larger fish with a longer life span. Examples include swordfish, shark, king mackerel, tilefish. The FDA recommends women of childbearing age and young children avoid these four types of fish. Pregnant women/women of childbearing age should consume up to 12 oz. of other fish (variety) each week. Canned albacore tuna has more mercury than light tuna and it should be limited to no more than 6 oz./week.