Vaccenic acid is a naturally occurring

trans fatty acid In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (triple e ...

. It is the predominant kind of trans-fatty acid found in

human milk Breast milk (sometimes spelled as breastmilk) or mother's milk is milk produced by mammary glands located in the breast of a human female. Breast milk is the primary source of nutrition for newborns, containing fat, protein, carbohydrates (lacto ...

, in the fat of

ruminant Ruminants (suborder Ruminantia) are hoofed herbivorous grazing or browsing mammals that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through microbial actions. The ...

s, and in dairy products such as

milk Milk is a white liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals (including breastfed human infants) before they are able to digest solid food. Immune factors and immune-modula ...

butter Butter is a dairy product made from the fat and protein components of churned cream. It is a semi-solid emulsion at room temperature, consisting of approximately 80% butterfat. It is used at room temperature as a spread, melted as a condimen ...

, and

yogurt Yogurt (; , from tr, yoğurt, also spelled yoghurt, yogourt or yoghourt) is a food produced by bacterial fermentation of milk. The bacteria used to make yogurt are known as ''yogurt cultures''. Fermentation of sugars in the milk by these bac ...

. Trans fat in human milk may depend on trans fat content in food. Its

IUPAC The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...

name is (11''E'')-11-octadecenoic acid, and its lipid shorthand name is 18:1 ''trans''-11. The name was derived from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''vacca'' (

cow Cattle (''Bos taurus'') are large, domesticated, cloven-hooved, herbivores. They are a prominent modern member of the subfamily Bovinae and the most widespread species of the genus ''Bos''. Adult females are referred to as cows and adult ma ...

). Vaccenic acid was discovered in 1928 in animal fats and

. Mammals convert it into

rumenic acid Rumenic acid, also known as bovinic acid, is a conjugated linoleic acid (CLA) found in the fat of ruminants and in dairy products. It is an omega-7 trans fatty acid. Its lipid shorthand name is cis-9, trans-11 18:2 acid. The name was proposed b ...

, a

conjugated linoleic acid Conjugated linoleic acids (CLA) are a family of isomers of linoleic acid. In principle, 28 isomers are possible. CLA is found mostly in the meat and dairy products derived from ruminants. The two C=C double bonds are conjugated (i.e., separated ...

, where it shows anticarcinogenic properties. Its stereoisomer, ''cis''-vaccenic acid, is an omega-7 fatty acid, is found in

Sea Buckthorn ''Hippophae'' is the genus of sea buckthorns, deciduous shrubs in the family Elaeagnaceae. The name sea buckthorn may be hyphenated to avoid confusion with the unrelated true buckthorns (''Rhamnus'', family Rhamnaceae). It is also referred to as ...

(''Hippophae rhamnoides'') oil. Its

name is (11''Z'')-11-octadecenoic acid, and its lipid shorthand name is 18:1 ''cis''-11.

Health

Vaccenic acid is also found in human

orbitofrontal cortex The orbitofrontal cortex (OFC) is a prefrontal cortex region in the frontal lobes of the brain which is involved in the cognitive process of decision-making. In non-human primates it consists of the association cortex areas Brodmann area 11, 1 ...

of patients with

bipolar disorder Bipolar disorder, previously known as manic depression, is a mental disorder characterized by periods of depression and periods of abnormally elevated mood that last from days to weeks each. If the elevated mood is severe or associated with ...

and

schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social wit ...

. Alkaline phosphatase inhibited 25% by vaccenic acid in osteoblasts. Oxidation of omega-7 unsaturated fatty acids on the skin surface, such as

palmitoleic acid Palmitoleic acid, or (9''Z'')-hexadec-9-enoic acid, is an omega-7 monounsaturated fatty acid (16:1n-7) with the formula CH3(CH2)5CH=CH(CH2)7COOH that is a common constituent of the glycerides of human adipose tissue. It is present in all tissues ...

and vaccenic acid, may be the cause of the phenomenon commonly known as

old person smell Old person smell is the characteristic odor of elderly humans. Much like many animal species, human odor undergoes distinct stages based on chemical changes initiated through the aging process. Research suggests that this enables humans to determi ...

. When fed vaccenic acid over 16 weeks, rats exhibited in lowered total

cholesterol Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell mem ...

, lowered

LDL Low-density lipoprotein (LDL) is one of the five major groups of lipoprotein that transport all fat molecules around the body in extracellular water. These groups, from least dense to most dense, are chylomicrons (aka ULDL by the overall densit ...

cholesterol and lower

triglyceride A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''wikt:tri-#Prefix, tri-'' and ''glyceride''). Triglycerides are the main constituents of body fat in humans and other ...

levels. Two Canadian studies have shown that vaccenic acid could be beneficial compared to vegetable

shortening Shortening is any fat that is a solid at room temperature and used to make crumbly pastry and other food products. Although butter is solid at room temperature and is frequently used in making pastry, the term ''shortening'' seldom refers to b ...

s containing trans fats, or a mixture of pork lard and soy fat, by lowering total

and triglyceride levels. A study by the US Department of Agriculture showed that vaccenic acid raises both HDL and LDL cholesterol, whereas industrial trans fats only raise LDL with no beneficial effect on HDL.David J. Baer, PhD. US Department of Agriculture, Agricultural Research Service, Beltsville Human Nutrition Research Laboratory
''New Findings on Dairy Trans Fat and Heart Disease Risk''
IDF World Dairy Summit 2010, 8–11 November 2010. Auckland, New Zealand

References

{{Fatty acids Fatty acids Animal fats Dairy products Alkenoic acids