Ácido erúcico: Diferenzas entre revisións

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=== Posibles problemas de saúde ===
== Health concerns ==
BeforeEstudos [[geneticen engineering]],ratas plantindicaron breedersproblemas were aiming to produce a less-bitter-tasting multi-purpose oil from rapeseed that would appeal to a larger market by making it more palatable for cattle and other livestock. While it was possible to breed out much of the pungent-tastingde [[glucosinolateslipidose]], onecando ofse thealimentaba dominantaos erucicanimais acidcon genesgrandes wouldcantidades getde strippedácido out of the [[genome]] as well, greatly reducing its valuable erucic acid content.{{citation needed|date=January 2012}} Studies on rats show [[lipidosis]] problems when fed high quantities of erucic acid, however, so this did not hinder saleability.erúcico<ref name=Charlton/> Later trials showed that rats had the same problems with other vegetable fatty acids,<ref>{{cite journal |author=Neat CE, Thomassen MS, Osmundsen H |title=Effects of high-fat diets on hepatic fatty acid oxidation in the rat. Isolation of rat liver peroxisomes by vertical-rotor centrifugation by using a self-generated, iso-osmotic, Percoll gradient |journal=Biochem. J. |volume=196 |issue=1 |pages=149–59 |year=1981 |month=April |pmid=6272750 |pmc=1162977 |doi= |url=}}</ref> becauseporque ratsas areratas poornon atmetabolizan metabolisingben somealguhas fatsgraxas.<ref name=Kramer>{{cite journal |author=Kramer JK, Hulan HW, Trenholm HL, Corner AH |title=Growth, lipid metabolism and pathology of two strains of rats fed high fat diets |journal=J. Nutr. |volume=109 |issue=2 |pages=202–13 |year=1979 |month=February |pmid=430222 |doi= |url=http://jn.nutrition.org/cgi/pmidlookup?view=long&pmid=430222}}</ref> The plant breeding industry later changed "low erucic acid" to be its [[unique selling proposition]] over that of its competitors.{{citation needed|date=October 2010}}
 
There are not many studies done on humans with erucic acid; the majority are carried out by the food science industry on animals. Animal studies failed to show negative events occurring from feeding of erucic acid, and the studies were repeated under increasingly unnatural scenarios. In one case, neonate piglets that have a limited ability to absorb these fats had their normal sow's milk replaced solely with rapeseed oil for one hundred percent of their calorific needs.<ref name=Kramer/> The studies showed that lipidoses suffered by the piglets proved to be only a transient effect; the liver automatically responded by increasing enzyme levels to cope with the unusual diet, and the lipidoses subsided.
 
==== Posibles problemas cardíacos====
A 2006 study reported higher rates of lung cancer in countries with populations that cook over solid fuel [[wood]] and [[biomass]] fires and stoves. The possibility of production of smoke from heated oil was also considered, and it was established that rapeseed oil, which contains erucic acid, can cause increased [[lung carcinoma]]s through emissions under high heat. However, the report also showed a variety of other cooking oils also did this at similar heats.<ref>S Kurt, Baan R, Grosse Y, Secretan B, (2006) [http://ehs.sph.berkeley.edu/krsmith/publications/2006%20pubs/Lancet-Oncology3.pdf Carcinogenicity of household solid fuel combustion and of high-temperature frying]. WHO International Agency for Research on Cancer Monograph Working Group. PDF 52kb. Retrieved 2007-01-29</ref>
TheOs levelsniveis ofpermitidos erucicde acidácido inerúcico humannos foodsalimentos arehumanos restrictedforon legalmente restrinxidos, inen partparte, overpola concernspreocupación thatde itque maypuidesen adverselyter affectafectos heartadversos tissuesobre o tecido cardíaco.<ref name=fsa /> O Erucicácido aciderúcico isé preferentiallyabsorbido absorbedpreferentemente indolo myocardiumtecido tissuedo [[miocardio]].<ref name=becker>{{cite journal |author=Becker W, Bruce A |title=Autoradiographic studies with fatty acids and some other lipids: a review |journal=Prog. Lipid Res. |volume=24 |issue=4 |pages=325–46 |year=1985 |pmid=3916594 |doi= 10.1016/0163-7827(85)90010-4|accessdate=2007-11-03}}</ref>
 
=== Cardiac concerns ===
The levels of erucic acid in human foods are restricted, in part, over concerns that it may adversely affect heart tissue.<ref name=fsa /> Erucic acid is preferentially absorbed in myocardium tissue<ref name=becker>{{cite journal |author=Becker W, Bruce A |title=Autoradiographic studies with fatty acids and some other lipids: a review |journal=Prog. Lipid Res. |volume=24 |issue=4 |pages=325–46 |year=1985 |pmid=3916594 |doi= 10.1016/0163-7827(85)90010-4|accessdate=2007-11-03}}</ref>
but is not metabolized there.<ref name=Kramer />
 
Nalgúns países establecéronse valores para o consumo diario deste ácido. En 2003 os Estándares de Alimentación de Australia estableceron un Consumo Diario Tolerable Provisorio (PTDI) duns 500&nbsp;mg/day de ácido erúcico, baseándose no "nivel que está asociado cun incremento de lipidose no miocardio nos porquiños lactantes."<ref name=fsa /> Nese país o ácido erúcico consumido pola poboación procede do aceite de colza, e o consumo individual medio é inferior ao PTDI, polo que non hai unha preocupación sobre a saúde pública, pero pode aproximarse a el se o consumo é máis alto e o nivel de ácido erúcico no aceite de colza excede o 2% do total de ácidos graxos."<ref name=fsa />
In 2003 Food Standards Australia set a Provisional Tolerable Daily Intake (PTDI) of about 500&nbsp;mg/day of erucic acid, based on "the level that is associated with increased myocardial lipidosis in nursling pigs."<ref name=fsa /> "There is a 120-fold safety margin between this level and the level that is associated with increased myocardial lipidosis in nursling pigs. The dietary exposure assessment has concluded that the majority of exposure to erucic acid
 
by the general population would come from the consumption of [[canola oil]]. The dietary intake of erucic acid by an individual consuming at the average level is well below the PTDI, therefore, there is no cause for concern in terms of public health and safety. However, the individual consuming at a high level has the potential to approach the PTDI. This would be particularly so if the level of erucic acid in canola oil was to exceed 2% of the total fatty acids."<ref name=fsa />
Na Unión Europea o máximo aceptado legalmente é o 5%.
 
== Notas ==