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Lipids

Dr. Taoufik
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A little history :

The therapeutic powers of certain oils have been used since ancient times. Snake oil for example, coming from traditional Chinese medicine, was taken from Chinese immigrants by the “charlatans” of the Wild West. It was recently discovered to be rich in fatty acids of the omega 3 series, such as the famous cod liver oil which was not only the popular remedy for rickets, but which was used in the 19th century by the English dermatologist Tilbury Fox. , to treat eczema, then by the pediatrician Trousseau in France as a supplement to prevent rickets in children (it took 30 years to get this admitted).

It was the Frenchman Michel Eugène Chevreul who discovered the chemical nature of fatty substances in 1814 and isolated cholesterol in 1816. In 1823, he published the first book on the biochemistry of fats. (Chevreul, advocate of a sober diet, lived 103 years).

More info: http://fr.wikipedia.org/wiki/Michel-Eugène_Chevreul

Ninety years later, in St. Petersburg, Anitschkow triggers atherosclerotic lesions in rabbits by feeding them only cholesterol.

Dutch doctor De Langen observes that inhabitants of the island of Java, who have a traditionally low diet in animal fats and have little atherosclerosis, experience an increase in their blood cholesterol when they adopt a European diet high in fat animal.

George Burr, a young researcher, arrived in 1924 in Evans’ laboratory in Berkeley, where vitamin E.

In 1927, he produced, with a diet containing practically no fatty acids, a new deficit picture in the rat. He married a technician from the laboratory and returned to Minnesota where they pursued together the experiments which led to the highlighting of the essentiality of two fatty acids: cis-linoleic acid and alpha-linolenic acid, which cannot be synthesized by the organism and essential for the growth of animals.

In 1933, Hansen, having observed the similarities between the signs of eczema and those of essential fatty acid deficiency, studied the effects of oral ingestion of different oils on children’s eczema, and proved that certain fatty acids were essential also in humans.

During the war, Hugh Sinclair, a doctor from Oxford, had the opportunity to study the diet of the Eskimos. By correlating Burr’s studies in animals and the statistical relationships between the frequency of disease and the ratio in the diet between essential fatty acids and saturated fatty acids, he came to the conclusion, in the mid-1950s, that , more than the excess of saturated fats, the deficit in essential fatty acids is a major factor in most degenerative pathologies, in particular cardiovascular, certain cancers, autoimmune diseases and multiple sclerosis …

In Portland, Oregon, Roy Swank, after noting that the frequency of multiple sclerosis was correlated with the consumption of dairy products, had already undertaken since 1949 to treat patients by rebalancing between saturated and unsaturated fats. He will follow 150 patients for 34 years and will demonstrate the effectiveness of the protocol in a pathology that is still without further treatment.

Other observations, like those of Catherine Kousmine and Michael Crawford, and controlled studies like those of Millar, will confirm and refine it.

In 1952, Klenk and Bongard put forward the importance of fatty acids of the omega 3 series, in particular DHA in the brain. But it will be more than forty years before some voices are raised and recommend to ensure to the pregnant and breastfeeding woman sufficient food sources of DHA (docosahexaenoic acid) to ensure a good development of the brain of the children.

In 1960, Denham Harman, who formulated the theory of free radicals four years earlier, suggested that fat oxidized by free radicals might be more important than unoxidized fat in atherosclerosis.

In 1965, Kaunitz caused heart and liver damage in rats by feeding them oxidized vegetable and animal fats.

Kritchevsky, in 1967, demonstrates that the fats of cooked oils are more atherogenic in rabbits than the fats of raw oils.

Tappel drew attention, as early as 1965, to the importance of Hpoperoxidation in degenerative pathologies and to the risk of consuming polyunsaturated fatty acids without a suitable intake of antioxidants such as vitamin E.

But again, it was not until more than thirty years before the accumulation of experimental, epidemiological and clinical data managed to make the medical community admit the insufficiencies of the “dogma of cholesterol”, the importance of oxidized LDL and vitamins. antioxidants.

Dyeberg and Bang clarify the observations of Hugh Sinclair: the fatty acids of fish, abundant in the food of the Eskimos, in particular the EPA (eicosapentaenoic acid), have antithrombotic effects.

Another old claim of Sinclair has to wait until the early 1980s to be substantiated: the trans fatty acids generated by the hydrogenation of oils, which allows to change from a liquid form to a solid form of margarine, are non-physiological; they can worsen, by competition, the deficits in essential fatty acids and have specific pathogenic effects. Current data confirms that they deplete essential fatty acids in cell membranes, inhibit their metabolism, increase LDL and decrease HDL, increase Lp (a) and platelet aggregation, c that is, they are powerfully atherogenic. Most recently, one of the most respected epidemiologists, Walter Willett, director of the School of Epidemiology and Public Health at Harvard,makes them responsible for at least 30,000 deaths per year in the United States.

Other studies suggest that trans fatty acids contribute: to the constitution of overweight in adults and hypotrophy in the fetus, because they cross the placental barrier; and probably also: a disturbance in brain development for which essential fatty acids are essential.

Functions of lipids:

They serve :

Lipids: Fatty acids – Triglycerides – Phospholipids – Steroids

Fatty acids:

A fatty acid is a molecule formed by a chain of carbons linked to hydrogens (this is what is called a hydrocarbon in organic chemistry) terminated by an acid group: COOH. Fatty acids constitute complex lipids generally comprising an even number of carbon atoms, oscillating between 12 and 22; they can be saturated. Carbon is tetravalent, capable of 4 bonds. If all of these are occupied, the fatty acid is saturated. If two carbons are linked by a double bond capable of opening to new atoms, it is unsaturated.

Triglycerides:

Triglycerides are made up of a molecule of glycerol, in the shape of a trident, which has reacted with three fatty acids. They represent a form of reserve of lipids in the cell, where they are concentrated within lipid vacuoles.

A fatty acid can bind to glycerol through its COOH group. The OH of one molecule reacts with the H of the other to form water.

As glycerol has three OH groups, it can therefore fix three fatty acids to thus form a triglyceride or triacylglycerol.

Role of triglycerides:

Triglycerides primarily serve as a form of fatty acid transport. Food surpluses of carbohydrates and fats can turn into triglycerides. Triglycerides distribute fatty acids to tissues, including adipose.

Digestion of triglycerides:

In the intestine, the triglyceride molecule is broken down into monoglyceride and two fatty acids.

Phospholipids:

Phospholipids look like triglycerides. They are formed from a glycerol linked to two fatty acids and to a phosphate group.

Most lipids spontaneously form micelles (small drops) in water because they are hydrophobic, they repel water. It is believed that the first cell membranes were formed in this way, life having most likely appeared in water, protected from ultraviolet radiation. Cell membranes make it possible to give a “home” to the genetic material which is at the heart of living things. They protect vital information from the external environment, allow the concentration of nutrients, useful minerals, etc. to reject waste.

Lipids are transported in the blood by lipoproteins associating a protein tag that gives it its destination, the protein having a key-lock relationship with a receptor located on the membrane of the recipient cell. For example LDL cholesterol are composed of cholesterol, cholesterol esters and the ApoB label which will bind to the LDL receptor and allow fatty acids to enter cells provided with this receptor. The ApoAl label characterizes HDL cholesterol which will therefore be directed to the bile and excreted in the digestive tract, hence its name of “good cholesterol” or return lipoprotein.

These lipoproteins are classified into 4 classes according to their density:

Steroids:

Lipids include terpenes and steroids.

The former are simple compounds of linear or cyclic conformation.

Steroids are derived from a terpene: squalene.

Sterols are alcohols derived from steroids, the most abundant in animal cells is cholesterol.

Sex hormones, those of the adrenal cortex, such as cortisone, aldosterone, SDHEA, progesterone, estrogen or testosterone, are steroids, derived from cholesterol. Coenzyme Q10 also has

precursor cholesterol.

Different chemical groups can attach themselves to the sterol core, thus forming different steroids.

Most of our cells make cholesterol. Almost 80% of the body’s cholesterol is thus synthesized. The rest comes from food.

Cholesterol, despite its bad reputation, is essential to our health:

We will review the properties of cholesterol in detail in module 8: Nutritherapy of cardiovascular pathologies. Also refer to the two DSNs (48 and 49) on the issue.

Properties of the different fatty acids:

Fatty acids are carbon chains. The carbon atom is tetravalent and can therefore bind to 4 other atoms.

Coding and representation:

The different lipids are identified by two numbers. The first number indicates the number of carbons in the fatty acid and the second the number of double bonds it carries. A fatty acid identified as 18: 2 is composed of 18 carbons carrying two double bonds (which can open to react with other atoms).

Fatty acids that have a single double bond are called monounsaturated. Usually the double bond is located on the 9th carbon, hence the name omega 9.

When they have several double bonds, they are called polyunsaturated. We add a code of the type n-3 or n-6 (we can also say omega-3 or omega-6). This code indicates the position of the first double bond in the chain (starting from the free end of the fatty acid). A 22: 5 n-3 fatty acid is therefore made up of 22 carbons carrying five double bonds. The first double bond connects carbon 3 to carbon 4 (carbons numbered starting from the free end of the chain). We distinguish those whose double bonds start at the 6th carbon, omega 6 and those who have even more, which requires to start from the third carbon, hence the name omega3.

FOR MORE INFO:

SATURATED fatty acids are:

Consequences :

In addition, the abundance of saturated fats in the diet unbalances the digestive flora and also has pro-inflammatory effects, contributing to overweight, cardiovascular risks, cancer and psychiatric pathologies. For example, we detect in autistic people, associated with excessive intakes of saturated fats, an abnormal rise in propionic acid which causes, in excess, in animals hyperactivity and stereotyped behaviors.

All this implies that an excess of saturated fatty acids (which is always the case, despite some progress in our diet) is a factor of

The major sources of saturated fat are butter, cheeses, milk, sour cream, pastries, palm oil overused in industrial products (cheap but devastating on forests), meats and cold cuts.

These foods rich in saturated fat are most often also sources of other nutrients

pro-inflammatory as in meats iron (violently pro-oxidant), arachidonic acid (precursor of pro-inflammatory prostaglandins), leucine (stimulant of the mTOR conductor of inflammation), to bacterial endotoxins and to pollutants. The pollutants currently of greatest concern are endocrine disruptors (present in food packaging but also in the environment) which are liposoluble and therefore concentrated and supplied in much greater quantities by fatty foods.

Saturated fats and fat-soluble pollutants have a synergistic (multiplier) effect in overweight, metabolic syndrome, diabetes, inflammatory pathologies, hormone-dependent cancers and mental disturbances.

It is not a question of eliminating saturated fats, but of avoiding excess and consuming them “clean”, therefore not in plastic packaging. The best alternative is the introduction of more monounsaturated fatty acids (for example substituting olive oil for butter as in Mediterranean regions).

Food sources:

MONO-UNSATURATED fatty acids are:

The sources of monounsaturated fatty acids are especially olive oil, avocado, almonds and their derivatives, goose and duck fat. The associated nutrients are rather protective, especially the polyphenols from virgin olive oil (the greenest and cloudiest) and whole almonds.

Some others, such as palmitoleic acid, have been put forward by the industry in modified sunflower oils called “oleisol”, which do not have the same advantages as olive oil (and are moreover marketed in bottles. plastics, which is unacceptable for an oil, as for any fatty substance: margarines, sauces, ready meals, etc.)

Food sources:

Poly-unsaturated fatty acids Omega 6 are:

– Are provided in too large quantities by the current diet, this is the case of cis-linoleic acid (sunflower oil, corn, grape seed, soybean, margarines and many agro-food products that use them) . What :

Public health advice, which is not always updated quickly enough, still often recommends oils and even sometimes, worse, margarines, rich in omega 6 fatty acids.

Margarines are even more harmful for two reasons: always in plastic tubs and hydrogenated.

Hydrogenation is an industrial process that transforms a liquid oil into a solid body and makes it more resistant to rancidity and aggression by cooking.

The problem is that the spatial shape of omega 6 fatty acids changes from cis to trans.

However, trans fatty acids have been shown to be more inflammatory, factors of cardiovascular disease, and even inhibitors of brain development in children than saturated fatty acids because they oppose the passage of omega 3 fatty acids in the brain.

This is also the case for arachidonic acid, a direct precursor of type 2 prostaglandins, pro-inflammatory, pro-allergic, vasoconstrictor, activator of platelets, unfavorable to estrogen-progestogen balance and lymphocyte proliferation (therefore to anti-infectious defenses), which is provided mainly by meats.

On the other hand, gamma-linolenic acid, a precursor via DGLA of type 1 prostaglandins, as protective as type 3 prostaglandins (series 1 and 3 have the opposite effects of series 2, with the exception of prostacyclin) is protective.

Unfortunately it is almost non-existent in the diet.

We can promote the production of gamma-linolenic acid from cis-linoleic acid, by giving delta 6 desaturase an optimized environment (reduction of saturated and trans fats, rapid sugars, zinc intake, its coenzyme ), or add it directly as a supplement (it is found in evening primrose and borage oils).

Food sources:

Inhibition of delta 6 desaturase:

Immature in the newborn and declining in the elderly

Deficiency in:

Excess in: 

We will see in detail the pro-inflammatory & anti-inflammatory properties of foods and nutrients in module 5: Allergies, Inflammatory and autoimmune pathologies

OMEGA 3 polyunsaturated fatty acids are:

Therefore they are:

Food sources:

Optimization of food intake and the use of omega three supplements:

Depression (significant correlation between depression and inflammation).

In addition, by inserting themselves into the membranes of bacteria and cancer cells, they make them vulnerable to oxidative attacks launched by white blood cells (hydrogen peroxide, bleach, etc.) and to attacks from radiotherapy and most chemotherapies that are pro-oxidant and are therefore also found in the first line in the treatment of bacterial infections and cancers.

Contraindications and precautions for use:

High dose omega three are contraindicated:

In any situation of bleeding or risk of bleeding:

They are subject to precautions for use in the event of taking anticoagulants, heavy periods, digestive tumor, oesophageal varices, significant risk of trauma (risky professions or sports), etc….

Omega three are also contraindicated in psychosis, because they stimulate all neurotransmissions.

In addition, being hyper-oxidizable, omega 3 (except indications of induction of pro-oxidant effects as in chemo / radiotherapy) must be combined with antioxidants (natural vitamin E. C, carotenoids. Selenium. NAC, coenzyme Q10 …). and polyphenols

If given in large doses over the long term, beware of an imbalance in the omega 6 side pathway of type 1 prostaglandins and also give gamma-linolenic acid (GLA).

In summary, fatty acids:

Fatty acids called “trans”:

They can be of natural origin (resulting from fermentation in ruminants), “technological”, “industrial” or “domestic” (cooking).

In “natural” trans fatty acids, we find:

In the category of “industrial or technological” trans fatty acids, we find:

Hydroqénisation:

This technique is used to transform liquid oils into solid fats as when it is necessary to make margarines which are used to make most of the agro-food products: margarines, breads, pastries, chocolate bars, cookies, quiches and other pastas. puff pastry, ready meals, spreads …

They are also most often packaged in plastic packaging which contains endocrine disruptors harmful to health which migrate into the products.

They can also come from the refining of oils during the deodorization step, which is carried out at high temperature.

In the category of domestic trans fatty acids, we find:

Why should you avoid trans fatty acids?

While experts agree that we should not exceed 1% of the AET (Total Energy Intake) of trans fatty acids, or 2.2 grams per day for intakes of 2000 kcal, the average consumption is about 3 grams per day in both children and adults and the maximum consumption observed in some children is 10 grams per day!

This situation explains why European consumer protection associations are pushing for these trans fatty acids to be removed and replaced by non-deleterious fatty acids, or for at least these fatty acids to be mentioned on labeling. Unfortunately, the food industry lobbyists are doing their jobs very effectively and convincingly. Five European countries (Austria, Denmark, Hungary, Iceland, Norway) and Switzerland have courageously taken the decision to ban trans fatty acids almost completely by regulation. In the United States, where their consumption is a real health disaster, some states have banned the presence of trans fatty acids in school canteens. Some other countries have opted for self-regulatory mechanisms. But for the others,the absence of any action plan or legislation remains more than worrying. They are not even on the labeling.

WHO launches the REPLACE plan against trans fatty acids. www.who.int/fr/news- room / detail / 14-05-2018-who-plan-to-eliminate-industrially-produced-trans-fatty-acids- from-global-food-supply

Note also that no food contains 100% of the same type of fatty acid. For each food, the proportion of fatty acids will vary. Thus, rapeseed oil, reputed to be rich in omega-3 (alpha-linolenic acid) also contains saturated fatty acids (9%), monounsaturated fatty acids (60%) and polyunsaturated fatty acids of which 22% d linoleic acid (omega-6) and 9% alpha-linolenic acid (omega-3). It actually contains as many saturated fatty acids as omega-3. But, this composition is unique and very interesting for our health.

Current recommendations for total lipids are 30 to 35% of the BET (total energy requirement) in Belgium and 35 to 40% in France. However, in a hundred years, the consumption of lipids has increased by 100% in our countries and is now clearly

surplus. The reason is simple. Lipids make foods tasty and creamy and therefore very clearly reinforce their organoleptic qualities, and therefore sales.

But there are lipids and lipids. We currently consume:

Optimization of fat intake is one of the major axes of systematic intervention of the nutritherapist.

Author Jean-Paul Curtay

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