Incorporation of EPA and DHA into plasma phospholipids in response to different omega-3 fatty acid formulations - a comparative bioavailability study of fish oil vs. krill oil

Abstract

BackgroundBioavailability of omega-3 fatty acids (FA) depends on their chemical form. Superior bioavailability has been suggested for phospholipid (PL) bound omega-3 FA in krill oil, but identical doses of different chemical forms have not been compared.MethodsIn a double-blinded crossover trial, we compared the uptake of three EPA+DHA formulations derived from fish oil (re-esterified triacylglycerides [rTAG], ethyl-esters [EE]) and krill oil (mainly PL). Changes of the FA compositions in plasma PL were used as a proxy for bioavailability. Twelve healthy young men (mean age 31 y) were randomized to 1680 mg EPA+DHA given either as rTAG, EE or krill oil. FA levels in plasma PL were analyzed pre-dose and 2, 4, 6, 8, 24, 48, and 72 h after capsule ingestion. Additionally, the proportion of free EPA and DHA in the applied supplements was analyzed.ResultsThe highest incorporation of EPA+DHA into plasma PL was provoked by krill oil (mean AUC0-72 h: 80.03 ± 34.71%*h), followed by fish oil rTAG (mean AUC0-72 h: 59.78 ± 36.75%*h) and EE (mean AUC0-72 h: 47.53 ± 38.42%*h). Due to high standard deviation values, there were no significant differences for DHA and the sum of EPA+DHA levels between the three treatments. However, a trend (p = 0.057) was observed for the differences in EPA bioavailability. Statistical pair-wise group comparison's revealed a trend (p = 0.086) between rTAG and krill oil. FA analysis of the supplements showed that the krill oil sample contained 22% of the total EPA amount as free EPA and 21% of the total DHA amount as free DHA, while the two fish oil samples did not contain any free FA.ConclusionFurther studies with a larger sample size carried out over a longer period are needed to substantiate our findings and to determine differences in EPA+DHA bioavailability between three common chemical forms of LC n-3 FA (rTAG, EE and krill oil). The unexpected high content of free EPA and DHA in krill oil, which might have a significant influence on the availability of EPA+DHA from krill oil, should be investigated in more depth and taken into consideration in future trials.

Higher efficacy of dietary DHA provided as a phospholipid than as a triglyceride for brain DHA accretion in neonatal piglets

“…More recently, interest in the potential effi cacy of PLs to deliver DHA has become of renewed interest also for use in adults with the widespread availability of krill oil. Krill oil carries greater than one-third of its high level of EPA and DHA as PLs ( 47 ), though notably, a recent report notes that about 22% of the EPA and DHA in one krill oil product is in the form of free FAs, which is at least several fold greater than normally found in foods or supplements ( 48 ). In the fi rst day postdose, the timing and peak of blood levels are generally greater when ingested as free FAs, and similar to those of TAGs ( 49,50 ) and/or as PLs compared with ethyl esters.…”

“…In the fi rst day postdose, the timing and peak of blood levels are generally greater when ingested as free FAs, and similar to those of TAGs ( 49,50 ) and/or as PLs compared with ethyl esters. However, these short-term kinetics may not correspond to long-term differences in DHA status as measured in human blood pools ( 48 ). Notably, however, blood FA status refl ects FAs in circulation and does not address the uptake and incorporation of specifi c FAs into target tissues, which can be measured directly with isotopically labeled precursors in animal models.…”

Fosfolípidos de origen marino: una nueva alternativa para la suplementación con ácidos grasos omega-3

“…La biodisponibilidad a nivel intestinal de los ácidos grasos, cuando son aportados en la forma de fosfolípidos, es sustancialmente mayor que cuando son aportados como triglicéri-dos (21), aspecto que es muy importante cuando se trata de suplementación con un tipo específico de ácidos grasos, por ejemplo EPA y/o DHA (26). Además, la estabilidad a la oxidación de los AGPICL, a la cual son muy susceptibles, es mayor cuando estos ácidos grasos se encuentran en la estructura de los fosfolípidos (27), aspecto que es de importancia desde el punto de vista de la estabilidad de las estructuras celulares y también de aquellos productos que sean adicionados de este tipo de fosfolípidos.…”

Ácido docosahexaenoico (DHA), un ácido graso esencial a nivel cerebral

“…Lamentablemente, en la actualidad la dieta occidental presenta un muy bajo aporte de DHA, situación que ha estimulado el desarrollo de alimentos y/o nutraceúticos que lo contienen en diferentes concentraciones y presentaciones, para lo cual se han realizado números esfuerzos destinados a obtener ingredientes factibles se ser utilizados como fuentes de DHA y a lograr incorporar este ácido graso en diversos alimentos (77). En relación a los ingredientes, hoy en día se dispone de aceites marinos (desodorizados, estabilizados y concentrados) ricos en DHA (sobre el 30% del total de ácidos grasos), DHA obtenido a partir de microalgas (como etilésteres o triacilglicéridos) y como fosfolípidos (aceite de krill) (78,79). En los últimos años se han desarrollado tecnologías de micro y nano-encapsulación de aceites ricos en DHA, lo cual ha permitido incorporar este ácido graso a diversas matrices alimentarias, particularmente leche y productos lác-teos, jugos, panes, galletas, entre otros, (77).…”