Analysis of long-chain omega-3 fatty acid content in fish-oil supplements.
BACKGROUND
Omega-3 polyunsaturated fatty acids (long-chain omega-3 PUFA) have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia in several studies, which has led national and international societies to recommend an intake of 1 g/d long-chain omega-3 PUFA for anti-atherosclerotic and antiarrhythmic purposes or 2-4 g/d for a lipid lowering effect. Numerous preparations are marketed for supplementing western diet, which is low in long-chain omega-3 PUFA. Since these preparations vary in their long-chain omega-3 PUFA content, we tested nine commercially available products for their fatty acid composition.


METHODS
Nine commercially available omega-3 fatty acid supplements were analyzed using capillary gas chromatography to determine their fatty acid content.


RESULTS
The nine preparations showed huge differences, up to 63.7 +/- 1.58 mol% (P = 0.002), in their longchain omega-3 fatty acid content. Most of them failed to achieve the daily recommended dose of 1 g, even when administered at the highest dosage according to the manufacturer's recommendations. Eight of the preparations contained either equal or significantly greater amounts of long-chain omega-3 PUFA than denoted by the manufacturer; one preparation did not provide any information. The highest percentage of DHA and EPA was detected in Omacor(95.80 +/- 0.63%) and Percucor (76.8 +/- 7.109%).


CONCLUSIONS
Administering long-chain omega-3 fatty acid preparations may result in huge differences in terms of the actual amount ingested. It is therefore advisable to use the most standardized and purified products available.
Tatarczyk
Tobias
T
Department of Internal Medicine, Clinical Division of General Internal Medicine, Medical University Innsbruck, Austria.
Engl
Julia
J
Ciardi
Christian
C
Laimer
Markus
M
Kaser
Susanne
S
Salzmann
Karin
K
Lenners
Ruth
R
Patsch
Josef R
JR
Ebenbichler
Christoph F
CF
D001145:Arrhythmias, Cardiac / Q000517:prevention & control*; D050197:Atherosclerosis / Q000517:prevention & control*; D002849:Chromatography, Gas; D019587:Dietary Supplements / Q000032:analysis*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000032:analysis*; D006801:Humans; D006949:Hyperlipidemias / Q000517:prevention & control*
D015525:Fatty Acids, Omega-3