Fats, oils and fatty acids

November 11/18/21, 2021from admin

Fats and oils are neutral compounds of:

trivalent alcohol glycerin
plus 3 fatty acid molecules

This combination is also called "triglycerides"These are broken down by special enzymes, the so-called lipases, into glycerin (which then enters the blood) and fatty acids.

Fats and oils have the same chemical structure. However, oils contain shorter fatty acids and, unlike fats, are therefore liquid at room temperature.

cis and trans fatty acids

Natural fatty acids are usually present in the so-called “cis” form, ie the C chains are located on one side of the double bond (three-dimensional), which makes the membrane structures more elastic. hydrogenated, so-called "trans" fatty acids usually produced artificially (see below). This makes the fatty acids two-dimensional and more rigid, no longer liquid and spreadable. However, this reduces the elasticity of the membrane structures.

Trans fatty acids increase the “bad” LDL cholesterol and lower the “good” HDL cholesterol, thus increasing the tendency to thrombosis. Their incorporation into cell walls leads to a rigid cell membrane and thus hinders organ functions.

Typical foods that may contain trans fatty acids are: margarine, mayonnaise, biscuits, savory biscuits, cakes, chocolate fillings, sweets and convenience foods.

"Artificial trans fats are considered a risk factor for cardiovascular disease. Consumption of these substances increases the level of LDL cholesterol in the blood. They cannot generally be considered safe," said the FDA (Food and Drug Administration).

(Source: Die Ärzte-Zeitung online, 11.11.2013)

Saturated and unsaturated fatty acids

The fatty acids are divided into

saturated fatty acids
monounsaturated fatty acids
polyunsaturated fatty acids (e.g. Omega 3, 6, 9 fatty acids)

The “saturation” is defined by the number of C=C double bonds. Saturated fatty acids have no double bonds, monounsaturated fatty acids have one, and polyunsaturated fatty acids have several double bonds.

Among the most famous saturated fatty acids to count

Lauric acid --> laurel oil, palm oil, animal fats
Myristic acid --> coconut oil, palm oil, animal fats
Palmitic acid --> palm oil, cottonseed oil, animal and vegetable fats, beeswax
Stearic acid --> animal and vegetable fats

Both unsaturated fatty acids the position of the double bond is important for the biochemical effect. In the classification, the position of the first double bond is determined from the methyl end (CH3) and is then the name-giving factor. This means that if the first double bond is, for example, at the third place from the methyl end, it is called “Omega 3“-fatty acids.

The two main representatives of polyunsaturated fatty acids are Omega 3 and the Omega 6 fatty acidsBoth fatty acids are "essential", meaning they must be obtained through the diet, whereas monounsaturated and monounsaturated fatty acids are not essential and can be synthesized by the body.

Omega 3 fatty acids

alpha-linolenic acid (ALA)
Mainly found in linseed oil, soybean oil, rapeseed oil and margarine
eicosapentaenoic acid (EPA)
Vafound in sea fish (salmon, mackerel, herring, sardines, tuna) and algae
docosahexaenoic acid (DHA)
Mainly found in sea fish and algae

Omega 6 fatty acids

linoleic acid

Found in safflower, sunflower, soy, corn and wheat germ oil as well as vegetable and diet margarine
(+) important for skin structure/skin barrier
(-) lowers the "good" cholesterol HDL
(-) can lead to LDL oxidation
gamma-linolenic acid
is synthesized, for example, in plant leaves from linoleic acid, hence basically the same effect profile
mainly found in hemp oil, evening primrose oil, borage oil
arachidonic acid
Found mainly in meat (also in small quantities in milk)
(-) During their metabolism, degradation products are produced that have an inflammatory effect.

Unsaturated fatty acids are starting materials for eicosanoids (“tissue hormones”), which have important control functions: in addition to cell division and platelet aggregation (blood clotting), they are primarily involved in inflammatory processes.

Important eicosanoids are

prostaglandins
prostacyclins
thromboxanes
leukotrienes

arachidonic acid (the “bad” Omega 6 fatty acid) is metabolized into

Prostaglandins 2 series
thromboxanes
Leukotrienes 4 series,
... all of which contribute to acute inflammation!

The Omega 3 fatty acid EPA on the other hand is metabolized into

Prostaglandins 3 series
Leukotriene 5 series
E-Resolvins (E1 inhibits the migration of inflammatory cells into the inflamed tissue and the formation of the messenger substance interleukin 12),
...which contribute to the active resolution of inflammation!

DHA is also metabolized into anti-inflammatory lipid mediators, especially in protectins and D-resolvins: Resolvin D2 causes endothelial cells to produce nitric oxide, which prevents the adhesion of leukocytes and thus their migration into the inflamed tissue.

Despite strong similarities in molecular structure, the biological functions of omega 3 and omega 6 fatty acids are very different:

Omega 3 fatty acids…

… provide only the “good” eicosanoids and inhibit the formation of “bad” eicosanoids from arachidonic acid
… works

anti-inflammatory
antirheumatic
cardioprotective
promote the mental development of the embryo

Omega 6 fatty acids…

… can form both anti-inflammatory (linoleic and linolenic acid), as well as pro-inflammatory (arachidonic acid / see above) and even carcinogenic eicosanoids, whereas Omega 3 only forms the “good”, anti-inflammatory eicosanoids (+/-)
ATTENTION: If large amounts of “good” Omega 6 fatty acids (linoleic/linolenic acid) are consumed, they can lead to increased formation of arachidonic acid, which promotes inflammation! Therefore, the ratio of Omega 6 to Omega 3 is important. In addition, the body needs the enzymes delta-6 and delta-5 desaturase to convert plant-based ALA into EPA/DHA.These two enzymes are also needed to convert the omega 6 fatty acid linoleic acid into other omega 6 fatty acids. By reducing the amount of omega 6 fatty acids in the diet, the body has more enzymes available to convert ALA into EPA/DHA.
In the Stone Age, the ratio of Omega 6 to Omega 3 was at 4:1. Due to livestock farming, fattening and agriculture, the ratio has continued to deteriorate to the detriment of omega 3 fatty acids and is now at ~20:1 in western societies (the DGE recommends a ratio of 5:1)!

… promote hemoglobin formation (hemoglobin is responsible for the transport of oxygen and CO2 in the blood) (+)
… have an important function during the division of the cell nucleus (mitosis) by ensuring the stability of the chromosomes in the cell nucleus (+)
… are important components of the double membrane of all cells and cell organelles
... accelerate the breakdown of lactate (lactate is a metabolic product of glycolysis; it is formed by the reduction of pyruvate to lactate; excess lactate makes legs heavy and muscles tired because they are over-acidified) (+)

Possible consequences of a lack of fatty acids

Omega 3 (essential)

Rheumatoid inflammations
Retarded Embryonic Development
sensory disturbances (MS!)
learning and visual impairments
growth disorders
Dry skin

Omega 6 (essential)

eczema
hair loss
susceptibility to infection
Delayed wound healing
growth disorders

The European Food Safety Authority (EFSA) recommends a daily intake of 250 mg EPA and/or DHA daily (as of March 2010).

DHA and EPA should always be taken with the meal richest in fat.

In recent years, further studies have shown that a dose of >2 g EPA/DHA per day is necessary for the prevention and treatment of common diseases:

2.2 g for good memory performance and to prevent Alzheimer's (Charité study, published in the Journal of Alzheimer Disease 02/2016)
4 g to achieve a high anti-inflammatory effect (Yates, Calder et. al. 2014)
2.7 g for rheumatism and for the gradual reduction of non-steroidal anti-inflammatory drugs (NSAIDs) (Lee YH1, Bae SC, Sng GG., 2012)
3-4 g for non-alcoholic fatty liver disease (Byrne, et. al. 2014 / Stephen, et. al. 2015)

There is a widespread misconception that alpha-linolenic acid (ALA) can be converted into EPA and DHA by the body and that vegetarians and vegans can therefore only meet their EPA and DHA requirements by consuming linseed oil, for example. Only a fraction of about 5% of ALA can be converted into EPA and ~0.5% into DHA. It is therefore not possible to ensure an adequate supply of the biochemically important DHA and EPA fatty acids without consuming fish or algae oil!

Health Claims

The scientifically proven effects of a dietary supplement are called “health claims”.These are as follows for DHA and EPA:

EPA and DHA contribute to normal heart function
EPA and DHA contribute to the maintenance of normal blood pressure
EPA and DHA contribute to the maintenance of normal triglyceride concentrations in the blood
DHA contributes to the maintenance of normal brain function
DHA contributes to the maintenance of normal vision
DHA contributes to the development of vision in young children
Maternal intake of docosahexaenoic acid (DHA) during pregnancy and breastfeeding contributes to the normal brain development of the fetus and the breastfed child
Maternal intake of docosahexaenoic acid (DHA) during pregnancy and breastfeeding contributes to the normal development of the eyes of the fetus and the breastfed child.

Conclusion

Finally, it should be noted that

the EPA and DHA content of an Omega 3 food supplement is crucial for its health-promoting effects is.
the highest levels of Omega 3 from high-quality fish oil in 500 mg EPA and 250 mg DHA per 1000 mg fish oil (Omega 3, 50/25 EPA/DHA) .
Algae oil currently at EPA, which is crucial for inhibiting inflammation, for example, significantly lower values comes.