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7272859 
Journal Article 
Why do omega-3 fatty acids lower serum triglycerides? 
Harris, WS; Bulchandani, D; , 
2006 
Yes 
Current Opinion in Lipidology
ISSN: 0957-9672
EISSN: 1080-823X 
LIPPINCOTT WILLIAMS & WILKINS 
PHILADELPHIA 
387-393 
16832161 
WOS:000239551900002 
Purpose of review Fish oils rich in n-3 fatty acids (n-3 FA) reduce serum triglycericle levels. This well known effect has been shown to be caused by decreased very low-density lipoprotein triglyceride secretion rates in kinetic studies in humans. Animal studies have explored the biochemical mechanisms underlying this effect. Triglyceride synthesis could be reduced by n-3 fatty acids in three general ways: reduced substrate (i.e. fatty acids) availability, which could be secondary to increase in R-oxidation, decreased free fatty acids delivery to the liver, decreased hepatic fatty acids synthesis; increased phospholipid synthesis; or decreased activity of triglyceride-synthesizing enzymes (diacylgylcerol acyltranferase or phosphatidic acid phosphohydrolase).Recent findings Rarely were experimental conditions used in rat studies physiologically relevant to the human situation in which 1.2% energy as n-3 fatty acids lowers serum triglyceride levels. Nevertheless, the most consistent effect of n-3 fatty acids feeding in rats is to decrease lipogenesis. Increased beta-oxidation was frequently, but not consistently, reported with similar numbers of studies reporting increased mitochondrial compared with peroxisomal oxidation. Inhibition of triglyceride-synthesizing enzymes was only occasionally noted.Summary As the vast majority of studies fed unphysiologically high doses of n-3 fatty acids, these findings in rats must be considered tentative, and the mechanism by which n-3 fatty acids reduce triglycericle levels in humans remains speculative.