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Docosahexaenoic acid

February 15, 2024

This article is about the omega-3 fatty acid. For the vitamin C metabolite also abbreviated as DHA, see Dehydroascorbic acid.

Docosahexaenoic acid (DHA) is an omega-3 fatty acid that is a primary structural component of the human brain, cerebral cortex, skin, and retina. In physiological literature, it is given the name 22:6(n-3). It can be synthesized from alpha-linolenic acid or obtained directly from maternal milk (breast milk), fatty fish, fish oil, or algae oil.[1]

Docosahexaenoic acid
Names
Preferred IUPAC name
(4Z,7Z,10Z,13Z,16Z,19Z)-Docosa-4,7,10,13,16,19-hexaenoic acid
Other names
cervonic acid
DHA
doconexent (INN)
Identifiers
  • 6217-54-5 Y
3D model (JSmol)
  • Interactive image
Abbreviations DHA
1715505
ChEBI
  • CHEBI:28125 Y
ChEMBL
  • ChEMBL367149 Y
ChemSpider
  • 393183 Y
DrugBank
  • DB03756
ECHA InfoCard 100.118.398
EC Number
  • 612-950-9
  • 1051
KEGG
  • C06429
  • 445580
UNII
  • ZAD9OKH9JC Y
  • DTXSID5040465
  • InChI=1S/C22H32O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-22(23)24/h3-4,6-7,9-10,12-13,15-16,18-19H,2,5,8,11,14,17,20-21H2,1H3,(H,23,24)/b4-3-,7-6-,10-9-,13-12-,16-15-,19-18- Y
    Key: MBMBGCFOFBJSGT-KUBAVDMBSA-N Y
  • InChI=1/C22H32O2/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-22(23)24/h3-4,6-7,9-10,12-13,15-16,18-19H,2,5,8,11,14,17,20-21H2,1H3,(H,23,24)/b4-3-,7-6-,10-9-,13-12-,16-15-,19-18-
    Key: MBMBGCFOFBJSGT-KUBAVDMBBZ
  • O=C(O)CC\C=C/C/C=C\C\C=C/C\C=C/C\C=C/C\C=C/CC
Properties
C22H32O2
Molar mass 328.488 g/mol
Density 0.943 g/cm3
Melting point −44 °C (−47 °F; 229 K)
Boiling point 446.7 °C (836.1 °F; 719.8 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)

DHA's structure is a carboxylic acid (-oic acid) with a 22-carbon chain (docosa- derives from the Ancient Greek for 22) and six (hexa-) cis double bonds (-en-);[2] with the first double bond located at the third carbon from the omega end.[3] Its trivial name is cervonic acid (from the Latin word cerebrum for "brain"), its systematic name is all-cis-docosa-4,7,10,13,16,19-hexa-enoic acid, and its shorthand name is 22:6(n−3) in the nomenclature of fatty acids.

Most of the docosahexaenoic acid in fish and multi-cellular organisms with access to cold-water oceanic foods originates from photosynthetic and heterotrophic microalgae, and becomes increasingly concentrated in organisms the further they are up the food chain. DHA is also commercially manufactured from microalgae: Crypthecodinium cohnii and another of the genus Schizochytrium.[non-primary source needed]

In organisms that do not eat algae containing DHA nor animal products containing DHA, DHA is instead produced internally from α-linolenic acid, a shorter omega-3 fatty acid manufactured by plants (and also occurring in animal products as obtained from plants).[4] Limited amounts of eicosapentaenoic and docosapentaenoic acids are possible products of α-linolenic acid metabolism in young women[5] and men.[4] DHA in breast milk is important for the developing infant.[6] Rates of DHA production in women are 15% higher than in men.[7]

DHA is a major fatty acid in brain phospholipids and the retina. Research into the potential role or benefit of DHA in various pathologies is ongoing,[8] with significant focus on its mechanism in Alzheimer's disease[9] and cardiovascular disease.[10]

Central nervous system constituent edit

DHA is the most abundant omega-3 fatty acid in the brain and retina.[11] DHA comprises 40% of the polyunsaturated fatty acids (PUFAs) in the brain and 60% of the PUFAs in the retina. Fifty percent of a neuronal plasma membrane is composed of DHA.[12] DHA modulates the carrier-mediated transport of choline, glycine, and taurine, the function of delayed rectifier potassium channels, and the response of rhodopsin contained in the synaptic vesicles.[13][14]

Phosphatidylserine (PS) – which contains high DHA content – has roles in neuronal signaling and neurotransmitter synthesis,[11] and DHA deficiency is associated with cognitive decline.[11][15] DHA levels are reduced in the brain tissue of severely depressed people.[16][17]

Biosynthesis edit

Aerobic eukaryote pathway edit

Aerobic eukaryotes, specifically microalgae, mosses, fungi, and some animals, perform biosynthesis of DHA usually occurs as a series of desaturation and elongation reactions, catalyzed by the sequential action of desaturase and elongase enzymes. This pathway, originally identified in Thraustochytrium, applies to these groups:[18]

  1. a desaturation at the sixth carbon of alpha-linolenic acid by a Δ6 desaturase to produce stearidonic acid (SDA, 18:3 ω-3),
  2. elongation of the stearidonic acid by a Δ6 elongase to produce to eicosatetraenoic acid (ETA, 20:4 ω-3),
  3. desaturation at the fifth carbon of eicosatetraenoic acid by a Δ5 desaturase to produce eicosapentaenoic acid (EPA, 20:5 ω-3),
  4. elongation of eicosapentaenoic acid by a Δ5 elongase to produce docosapentaenoic acid (DPA, 22:5 ω-3), and
  5. desaturation at the fourth carbon of docosapentaenoic acid by a Δ4 desaturase to produce DHA.

Mammals edit

In humans, DHA is either obtained from the diet or may be converted in small amounts from eicosapentaenoic acid (EPA, 20:5, ω-3). With the identification of FADS2 as a human Δ4-desaturase in 2015, it is now known that humans also use follow latter part of the above "aerobic eukaryote" pathway, involving to Δ5-elongation to DPA and Δ4-desaturation to DHA.[19]

Although the DPA route was the original proposed pathway for humans,[5][4] scientists have long tried and failed to find a Δ4-desaturase in mammals since its proposal.[18] This gave credence to the alternative "Sprecher's shunt" hypothesis, in which EPA is twice elongated to 24:5 ω-3, then desaturated to 24:6 ω-3 (via delta 6 desaturase) in the mitochondria, then shortened to DHA (22:6 ω-3) via beta oxidation in the peroxisome.[20][21] However, the shunt model does not match clinical data, specifically as patients with beta oxidation defects do not display issues in DHA synthesis. With the identification of a Δ4-desaturase, it is considered outdated.[19]

Anaerobic pathway edit

Marine bacteria and the microalgae Schizochytrium use an anerobic polyketide synthase pathway to synthesize DHA.[18]

Metabolism edit

DHA can be metabolized into DHA-derived specialized pro-resolving mediators (SPMs), DHA epoxides, electrophilic oxo-derivatives (EFOX) of DHA, neuroprostanes, ethanolamines, acylglycerols, docosahexaenoyl amides of amino acids or neurotransmitters, and branched DHA esters of hydroxy fatty acids, among others.[22]

The enzyme CYP2C9 metabolizes DHA to epoxydocosapentaenoic acids (EDPs; primarily 19,20-epoxy-eicosapentaenoic acid isomers [i.e. 10,11-EDPs]).[23]

Potential health effects edit

See also: Omega-3 fatty acid § Health effects

Cardiovascular edit

Though mixed and plagued by methodological inconsistencies, there is now convincing evidence from ecological, RCTs, meta-analyses and animal trials show a benefit for omega-3 dietary intake for cardiovascular health.[10] Of the n-3 FAs, DHA has been argued to be the most beneficial due to its preferential uptake in the myocardium, its strongly anti-inflammatory activity and its metabolism toward neuroprotectins and resolvins, the latter of which directly contribute to cardiac function.[24]

Pregnancy and lactation edit

Foods high in omega-3 fatty acids may be recommended to women who want to become pregnant or when nursing.[25] A working group from the International Society for the Study of Fatty Acids and Lipids recommended 300 mg/day of DHA for pregnant and lactating women, whereas the average consumption was between 45 mg and 115 mg per day of the women in the study, similar to a Canadian study.[26]

Brain and visual functions edit

A major structural component of the mammalian central nervous system, DHA is the most abundant omega−3 fatty acid in the brain and retina.[27] Brain and retinal function rely on dietary intake of DHA to support a broad range of cell membrane and cell signaling properties, particularly in grey matter and retinal photoreceptor cell outer segments, which are rich in membranes.[28][29]

A systematic review found that DHA had no significant benefits in improving visual field in individuals with retinitis pigmentosa.[30] Animal research shows effect of oral intake of deuterium-reinforced DHA (D-DHA) for prevention of macular degeneration.[31]

Nutrition edit

 
Algae-based DHA supplements

Ordinary types of cooked salmon contain 500–1500 mg DHA and 300–1000 mg EPA per 100 grams.[32] Additional rich seafood sources of DHA include caviar (3400 mg per 100 grams), anchovies (1292 mg per 100 grams), mackerel (1195 mg per 100 grams), and cooked herring (1105 mg per 100 grams).[32]

Brains from mammals taken as food are also a good direct source. Beef brain, for example, contains approximately 855 mg of DHA per 100 grams in a serving.[33] While DHA may be the primary fatty acid found in certain specialized tissues, these tissues, aside from the brain, are typically small in size, such as the seminiferous tubules and the retina. As a result, animal-based foods, excluding the brain, generally offer minimal amounts of preformed DHA.[34]

Discovery of algae-based DHA edit

In the early 1980s, NASA sponsored scientific research on a plant-based food source that could generate oxygen and nutrition on long-duration space flights. Certain species of marine algae produced rich nutrients, leading to the development of an algae-based, vegetable-like oil that contains two polyunsaturated fatty acids, DHA and arachidonic acid.[35]

Use as a food additive edit

DHA is widely used as a food supplement. It was first used primarily in infant formulas.[36] In 2019, the US Food and Drug Administration published qualified health claims for DHA.[37]

Some manufactured DHA is a vegetarian product extracted from algae, and it competes on the market with fish oil that contains DHA and other omega-3s such as EPA. Both fish oil and DHA are odorless and tasteless after processing as a food additive.[38]

Studies of vegetarians and vegans edit

Main article: Vegetarian nutrition § Omega-3 fatty acids

Vegetarian diets typically contain limited amounts of DHA, and vegan diets typically contain no DHA.[39] In preliminary research, algae-based supplements increased DHA levels.[40] While there is little evidence of adverse health or cognitive effects due to DHA deficiency in adult vegetarians or vegans, breast milk levels remain a concern for supplying adequate DHA to the infant.[39]

DHA and EPA in fish oils edit

Fish oil is widely sold in capsules containing a mixture of omega-3 fatty acids, including EPA and DHA. Oxidized fish oil in supplement capsules may contain lower levels of EPA and DHA.[41][42] Light, oxygen exposure, and heat can all contribute to oxidation of fish oil supplements.[41][42] Buying a quality product that is kept cold in storage and then keeping it in a refrigerator can help minimize oxidation.[43]

Hypothesized role in human evolution edit

DHA supply is a limiting factor in adult brain size.[34] An abundance of DHA in seafood has been suggested as being helpful in the development of a large brain,[44] though other researchers claim a terrestrial diet could also have provided the necessary DHA.[45]

See also edit

References edit

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  2. ^ . Archived from the original on 2013-07-07. Retrieved 2012-04-21.
  3. ^ The omega end is the one furthest from the carboxyl group.
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  5. ^ a b Burdge, G. C.; Wootton, S. A. (2002). "Conversion of alpha-linolenic acid to eicosapentaenoic, docosapentaenoic and docosahexaenoic acids in young women". British Journal of Nutrition. 88 (4): 411–20. doi:10.1079/BJN2002689. PMID 12323090.
  6. ^ Malone, J. Patrick (2012). "The Systems Theory of Autistogenesis: Putting the Pieces Together". SAGE Open. 2 (2): 215824401244428. doi:10.1177/2158244012444281.
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  22. ^ Kuda, Ondrej (2017). "Bioactive metabolites of docosahexaenoic acid". Biochimie. 136: 12–20. doi:10.1016/j.biochi.2017.01.002. PMID 28087294.
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  24. ^ Mclennan, Peter (2014). "Cardiac physiology and clinical efficacy of dietary fish oil clarified through cellular mechanisms of omega-3 polyunsaturated fatty acids". European Journal of Applied Physiology. 114 (7): 1333–1356. doi:10.1007/s00421-014-2876-z. PMID 24699892. S2CID 959967.
  25. ^ Harvard School Of Public Health (18 September 2012). "Omega-3 Fatty Acids: An Essential Contribution". Retrieved 12 June 2015.
  26. ^ Denomme J, Stark KD, Holub BJ (2005). "Directly quantitated dietary (n-3) fatty acid intakes of pregnant Canadian women are lower than current dietary recommendations". The Journal of Nutrition. 135 (2): 206–11. doi:10.1093/jn/135.2.206. PMID 15671214.
  27. ^ Hüppi PS (March 2008). "Nutrition for the brain: commentary on the article by Isaacs et al. on page 308" (PDF). Pediatric Research. 63 (3): 229–31. doi:10.1203/pdr.0b013e318168c6d1. PMID 18287959. S2CID 6564743.
  28. ^ Harris WS, Baack ML (January 2015). "Beyond building better brains: bridging the docosahexaenoic acid (DHA) gap of prematurity". Journal of Perinatology. 35 (1): 1–7. doi:10.1038/jp.2014.195. PMC 4281288. PMID 25357095.
  29. ^ SanGiovanni JP, Chew EY (January 2005). "The role of omega-3 long-chain polyunsaturated fatty acids in health and disease of the retina". Progress in Retinal and Eye Research. 24 (1): 87–138. doi:10.1016/j.preteyeres.2004.06.002. PMID 15555528. S2CID 13757616.
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  33. ^ "Beef, variety meats and by-products, brain, cooked, simmered". Retrieved 2011-10-27.
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  35. ^ Jones, John. . May 1st, 2001. NASA. Archived from the original on 1997-06-18.
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  37. ^ "FDA Announces New Qualified Health Claims for EPA and DHA Omega-3 Consumption and the Risk of Hypertension and Coronary Heart Disease". US Food and Drug Administration. 19 June 2019. Retrieved 30 August 2019.
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  40. ^ Lane, K; Derbyshire, E; Li, W; Brennan, C (2014). "Bioavailability and potential uses of vegetarian sources of omega-3 fatty acids: A review of the literature". Critical Reviews in Food Science and Nutrition. 54 (5): 572–9. doi:10.1080/10408398.2011.596292. PMID 24261532. S2CID 30307483.
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  45. ^ Carlson BA, Kingston JD (2007). "Docosahexaenoic acid biosynthesis and dietary contingency: Encephalization without aquatic constraint". Am. J. Hum. Biol. 19 (4): 585–8. doi:10.1002/ajhb.20683. PMID 17546613. S2CID 21419886.

February 15, 2024
docosahexaenoic, acid, this, article, about, omega, fatty, acid, vitamin, metabolite, also, abbreviated, dehydroascorbic, acid, omega, fatty, acid, that, primary, structural, component, human, brain, cerebral, cortex, skin, retina, physiological, literature, g. This article is about the omega 3 fatty acid For the vitamin C metabolite also abbreviated as DHA see Dehydroascorbic acid Docosahexaenoic acid DHA is an omega 3 fatty acid that is a primary structural component of the human brain cerebral cortex skin and retina In physiological literature it is given the name 22 6 n 3 It can be synthesized from alpha linolenic acid or obtained directly from maternal milk breast milk fatty fish fish oil or algae oil 1 Docosahexaenoic acid NamesPreferred IUPAC name 4Z 7Z 10Z 13Z 16Z 19Z Docosa 4 7 10 13 16 19 hexaenoic acidOther names cervonic acidDHAdoconexent INN IdentifiersCAS Number 6217 54 5 Y3D model JSmol Interactive imageAbbreviations DHABeilstein Reference 1715505ChEBI CHEBI 28125 YChEMBL ChEMBL367149 YChemSpider 393183 YDrugBank DB03756ECHA InfoCard 100 118 398EC Number 612 950 9IUPHAR BPS 1051KEGG C06429PubChem CID 445580UNII ZAD9OKH9JC YCompTox Dashboard EPA DTXSID5040465InChI InChI 1S C22H32O2 c1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 h3 4 6 7 9 10 12 13 15 16 18 19H 2 5 8 11 14 17 20 21H2 1H3 H 23 24 b4 3 7 6 10 9 13 12 16 15 19 18 YKey MBMBGCFOFBJSGT KUBAVDMBSA N YInChI 1 C22H32O2 c1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 h3 4 6 7 9 10 12 13 15 16 18 19H 2 5 8 11 14 17 20 21H2 1H3 H 23 24 b4 3 7 6 10 9 13 12 16 15 19 18 Key MBMBGCFOFBJSGT KUBAVDMBBZSMILES O C O CC C C C C C C C C C C C C C C C C C CCPropertiesChemical formula C22H32O2Molar mass 328 488 g molDensity 0 943 g cm3Melting point 44 C 47 F 229 K Boiling point 446 7 C 836 1 F 719 8 K Except where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references DHA s structure is a carboxylic acid oic acid with a 22 carbon chain docosa derives from the Ancient Greek for 22 and six hexa cis double bonds en 2 with the first double bond located at the third carbon from the omega end 3 Its trivial name is cervonic acid from the Latin word cerebrum for brain its systematic name is all cis docosa 4 7 10 13 16 19 hexa enoic acid and its shorthand name is 22 6 n 3 in the nomenclature of fatty acids Most of the docosahexaenoic acid in fish and multi cellular organisms with access to cold water oceanic foods originates from photosynthetic and heterotrophic microalgae and becomes increasingly concentrated in organisms the further they are up the food chain DHA is also commercially manufactured from microalgae Crypthecodinium cohnii and another of the genus Schizochytrium non primary source needed In organisms that do not eat algae containing DHA nor animal products containing DHA DHA is instead produced internally from a linolenic acid a shorter omega 3 fatty acid manufactured by plants and also occurring in animal products as obtained from plants 4 Limited amounts of eicosapentaenoic and docosapentaenoic acids are possible products of a linolenic acid metabolism in young women 5 and men 4 DHA in breast milk is important for the developing infant 6 Rates of DHA production in women are 15 higher than in men 7 DHA is a major fatty acid in brain phospholipids and the retina Research into the potential role or benefit of DHA in various pathologies is ongoing 8 with significant focus on its mechanism in Alzheimer s disease 9 and cardiovascular disease 10 Contents 1 Central nervous system constituent 2 Biosynthesis 2 1 Aerobic eukaryote pathway 2 2 Mammals 2 3 Anaerobic pathway 3 Metabolism 4 Potential health effects 4 1 Cardiovascular 4 2 Pregnancy and lactation 4 3 Brain and visual functions 5 Nutrition 5 1 Discovery of algae based DHA 5 2 Use as a food additive 5 3 Studies of vegetarians and vegans 5 4 DHA and EPA in fish oils 6 Hypothesized role in human evolution 7 See also 8 ReferencesCentral nervous system constituent editDHA is the most abundant omega 3 fatty acid in the brain and retina 11 DHA comprises 40 of the polyunsaturated fatty acids PUFAs in the brain and 60 of the PUFAs in the retina Fifty percent of a neuronal plasma membrane is composed of DHA 12 DHA modulates the carrier mediated transport of choline glycine and taurine the function of delayed rectifier potassium channels and the response of rhodopsin contained in the synaptic vesicles 13 14 Phosphatidylserine PS which contains high DHA content has roles in neuronal signaling and neurotransmitter synthesis 11 and DHA deficiency is associated with cognitive decline 11 15 DHA levels are reduced in the brain tissue of severely depressed people 16 17 Biosynthesis editAerobic eukaryote pathway edit Aerobic eukaryotes specifically microalgae mosses fungi and some animals perform biosynthesis of DHA usually occurs as a series of desaturation and elongation reactions catalyzed by the sequential action of desaturase and elongase enzymes This pathway originally identified in Thraustochytrium applies to these groups 18 a desaturation at the sixth carbon of alpha linolenic acid by a D6 desaturase to produce stearidonic acid SDA 18 3 w 3 elongation of the stearidonic acid by a D6 elongase to produce to eicosatetraenoic acid ETA 20 4 w 3 desaturation at the fifth carbon of eicosatetraenoic acid by a D5 desaturase to produce eicosapentaenoic acid EPA 20 5 w 3 elongation of eicosapentaenoic acid by a D5 elongase to produce docosapentaenoic acid DPA 22 5 w 3 and desaturation at the fourth carbon of docosapentaenoic acid by a D4 desaturase to produce DHA Mammals edit In humans DHA is either obtained from the diet or may be converted in small amounts from eicosapentaenoic acid EPA 20 5 w 3 With the identification of FADS2 as a human D4 desaturase in 2015 it is now known that humans also use follow latter part of the above aerobic eukaryote pathway involving to D5 elongation to DPA and D4 desaturation to DHA 19 Although the DPA route was the original proposed pathway for humans 5 4 scientists have long tried and failed to find a D4 desaturase in mammals since its proposal 18 This gave credence to the alternative Sprecher s shunt hypothesis in which EPA is twice elongated to 24 5 w 3 then desaturated to 24 6 w 3 via delta 6 desaturase in the mitochondria then shortened to DHA 22 6 w 3 via beta oxidation in the peroxisome 20 21 However the shunt model does not match clinical data specifically as patients with beta oxidation defects do not display issues in DHA synthesis With the identification of a D4 desaturase it is considered outdated 19 Anaerobic pathway edit Marine bacteria and the microalgae Schizochytrium use an anerobic polyketide synthase pathway to synthesize DHA 18 Metabolism editDHA can be metabolized into DHA derived specialized pro resolving mediators SPMs DHA epoxides electrophilic oxo derivatives EFOX of DHA neuroprostanes ethanolamines acylglycerols docosahexaenoyl amides of amino acids or neurotransmitters and branched DHA esters of hydroxy fatty acids among others 22 The enzyme CYP2C9 metabolizes DHA to epoxydocosapentaenoic acids EDPs primarily 19 20 epoxy eicosapentaenoic acid isomers i e 10 11 EDPs 23 Potential health effects editSee also Omega 3 fatty acid Health effects Cardiovascular edit Though mixed and plagued by methodological inconsistencies there is now convincing evidence from ecological RCTs meta analyses and animal trials show a benefit for omega 3 dietary intake for cardiovascular health 10 Of the n 3 FAs DHA has been argued to be the most beneficial due to its preferential uptake in the myocardium its strongly anti inflammatory activity and its metabolism toward neuroprotectins and resolvins the latter of which directly contribute to cardiac function 24 Pregnancy and lactation edit Foods high in omega 3 fatty acids may be recommended to women who want to become pregnant or when nursing 25 A working group from the International Society for the Study of Fatty Acids and Lipids recommended 300 mg day of DHA for pregnant and lactating women whereas the average consumption was between 45 mg and 115 mg per day of the women in the study similar to a Canadian study 26 Brain and visual functions edit A major structural component of the mammalian central nervous system DHA is the most abundant omega 3 fatty acid in the brain and retina 27 Brain and retinal function rely on dietary intake of DHA to support a broad range of cell membrane and cell signaling properties particularly in grey matter and retinal photoreceptor cell outer segments which are rich in membranes 28 29 A systematic review found that DHA had no significant benefits in improving visual field in individuals with retinitis pigmentosa 30 Animal research shows effect of oral intake of deuterium reinforced DHA D DHA for prevention of macular degeneration 31 Nutrition edit nbsp Algae based DHA supplementsOrdinary types of cooked salmon contain 500 1500 mg DHA and 300 1000 mg EPA per 100 grams 32 Additional rich seafood sources of DHA include caviar 3400 mg per 100 grams anchovies 1292 mg per 100 grams mackerel 1195 mg per 100 grams and cooked herring 1105 mg per 100 grams 32 Brains from mammals taken as food are also a good direct source Beef brain for example contains approximately 855 mg of DHA per 100 grams in a serving 33 While DHA may be the primary fatty acid found in certain specialized tissues these tissues aside from the brain are typically small in size such as the seminiferous tubules and the retina As a result animal based foods excluding the brain generally offer minimal amounts of preformed DHA 34 Discovery of algae based DHA edit In the early 1980s NASA sponsored scientific research on a plant based food source that could generate oxygen and nutrition on long duration space flights Certain species of marine algae produced rich nutrients leading to the development of an algae based vegetable like oil that contains two polyunsaturated fatty acids DHA and arachidonic acid 35 Use as a food additive edit DHA is widely used as a food supplement It was first used primarily in infant formulas 36 In 2019 the US Food and Drug Administration published qualified health claims for DHA 37 Some manufactured DHA is a vegetarian product extracted from algae and it competes on the market with fish oil that contains DHA and other omega 3s such as EPA Both fish oil and DHA are odorless and tasteless after processing as a food additive 38 Studies of vegetarians and vegans edit Main article Vegetarian nutrition Omega 3 fatty acids Vegetarian diets typically contain limited amounts of DHA and vegan diets typically contain no DHA 39 In preliminary research algae based supplements increased DHA levels 40 While there is little evidence of adverse health or cognitive effects due to DHA deficiency in adult vegetarians or vegans breast milk levels remain a concern for supplying adequate DHA to the infant 39 DHA and EPA in fish oils edit Fish oil is widely sold in capsules containing a mixture of omega 3 fatty acids including EPA and DHA Oxidized fish oil in supplement capsules may contain lower levels of EPA and DHA 41 42 Light oxygen exposure and heat can all contribute to oxidation of fish oil supplements 41 42 Buying a quality product that is kept cold in storage and then keeping it in a refrigerator can help minimize oxidation 43 Hypothesized role in human evolution editDHA supply is a limiting factor in adult brain size 34 An abundance of DHA in seafood has been suggested as being helpful in the development of a large brain 44 though other researchers claim a terrestrial diet could also have provided the necessary DHA 45 See also editDHA clozapine List of omega 3 fatty acids Polyunsaturated fatty acidsReferences edit Guesnet P Alessandri JM 2011 Docosahexaenoic acid DHA and the developing central nervous system CNS Implications for dietary recommendations Biochimie 93 1 7 12 doi 10 1016 j biochi 2010 05 005 PMID 20478353 Dictionary Definition of DocosahexaenoicAcids Archived from the original on 2013 07 07 Retrieved 2012 04 21 The omega end is the one furthest from the carboxyl group a b c Burdge G C Jones A E Wootton S A 2002 Eicosapentaenoic and docosapentaenoic acids are the principal products of a linolenic acid metabolism in young men British Journal of Nutrition 88 4 355 363 doi 10 1079 BJN2002662 PMID 12323085 a b Burdge G C Wootton S A 2002 Conversion of alpha linolenic acid to eicosapentaenoic docosapentaenoic and docosahexaenoic acids in young women British Journal of Nutrition 88 4 411 20 doi 10 1079 BJN2002689 PMID 12323090 Malone J Patrick 2012 The Systems Theory of Autistogenesis Putting the Pieces Together SAGE Open 2 2 215824401244428 doi 10 1177 2158244012444281 Giltay EJ Gooren LJ Toorians AW Katan MB Zock PL 2004 Docosahexaenoic acid concentrations are higher in women than in men because of estrogenic effects The American Journal of Clinical Nutrition 80 5 1167 74 doi 10 1093 ajcn 80 5 1167 PMID 15531662 Ghasemi Fard Samenah et al 2019 How does high DHA fish oil affect health A systematic review of evidence Critical Reviews in Food Science and Nutrition 59 11 1684 1727 doi 10 1080 10408398 2018 1425978 PMID 29494205 S2CID 4638292 Cederholm T Salem N Jr Palmblad J 2013 w 3 fatty acids in the prevention of cognitive decline in humans Adv Nutr 4 6 672 6 doi 10 3945 an 113 004556 PMC 3823515 PMID 24228198 a b Innes Jacqueline Calder Philip 2020 Marine Omega 3 N 3 Fatty Acids for Cardiovascular Health An Update for 2020 International Journal of Molecular Sciences v 21 1362 doi 10 3390 ijms21041362 PMC 7072971 PMID 32085487 a b c Kim Hee Yong Huang Bill X Spector Arthur A 2014 Phosphatidylserine in the brain Metabolism and function Progress in Lipid Research 56 1 18 doi 10 1016 j plipres 2014 06 002 ISSN 0163 7827 PMC 4258547 PMID 24992464 Singh Meharban March 2005 Essential fatty acids DHA and the human brain PDF Indian Journal of Pediatrics 72 3 239 242 doi 10 1007 BF02859265 PMID 15812120 S2CID 5067744 Archived from the original PDF on February 27 2012 Retrieved October 8 2007 Spector Arthur A Kim Hee Yong 2015 Discovery of essential fatty acids Journal of Lipid 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2002 FDA Announces New Qualified Health Claims for EPA and DHA Omega 3 Consumption and the Risk of Hypertension and Coronary Heart Disease US Food and Drug Administration 19 June 2019 Retrieved 30 August 2019 Rivlin Gary 2007 01 14 Magical or Overrated A Food Additive in a Swirl The New York Times Retrieved 2007 01 15 a b Sanders T A 2009 DHA status of vegetarians Prostaglandins Leukotrienes and Essential Fatty Acids 81 2 3 137 41 doi 10 1016 j plefa 2009 05 013 PMID 19500961 Lane K Derbyshire E Li W Brennan C 2014 Bioavailability and potential uses of vegetarian sources of omega 3 fatty acids A review of the literature Critical Reviews in Food Science and Nutrition 54 5 572 9 doi 10 1080 10408398 2011 596292 PMID 24261532 S2CID 30307483 a b Albert Benjamin B 21 January 2015 Fish oil supplements in New Zealand are highly oxidised and do not meet label content of n 3 PUFA release Scientific Reports 5 7928 doi 10 1038 srep07928 PMC 4300506 PMID 25604397 a b Albert Benjamin B Cameron Smith David Hofman Paul L Cutfield Wayne S 2013 Oxidation of Marine Omega 3 Supplements and Human Health BioMed Research International 2013 464921 doi 10 1155 2013 464921 PMC 3657456 PMID 23738326 Zargar Atanaz Ito Matthew K 1 August 2011 Long chain omega 3 dietary supplements a review of the National Library of Medicine Herbal Supplement Database Metabolic Syndrome and Related Disorders 9 4 255 271 doi 10 1089 met 2011 0004 ISSN 1557 8518 PMID 21787228 Crawford M et al 2000 Evidence for the unique function of docosahexaenoic acid DHA during the evolution of the modern hominid brain Lipids 34 S1 S39 S47 doi 10 1007 BF02562227 PMID 10419087 S2CID 4060454 Carlson BA Kingston JD 2007 Docosahexaenoic acid biosynthesis and dietary contingency Encephalization without aquatic constraint Am J Hum Biol 19 4 585 8 doi 10 1002 ajhb 20683 PMID 17546613 S2CID 21419886 Retrieved from https en wikipedia org w index php title Docosahexaenoic acid amp oldid 1203875647, wikipedia, wiki, book, books, 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