There is increasing evidence that serum triglycerides are a significant and independent risk factor for CVD. The aim of this report is to review recent literature pertinent to the triglyceride-lowering effect of omega-3 long chain polyunsaturated fatty acids (LC-PUFA). Animal data are not considered because they are difficult to extrapolate to the human situation. A large body of evidence derived from epidemiological studies and clinical trials has consistently demonstrated that this effect is dose-dependent and can be achieved by diet. The smallest amount of omega-3 LC-PUFA needed to significantly lower serum triglycerides appears to be approximately 1 g/day as provided by a fish diet. Use of fish oil administering as little as 0.21 g EPA and 0.12 g DHA per day significantly lowered serum triglycerides in hyperlipidemics. In normolipidemics, a daily intake of 0.17 g EPA and 0.11 g DHA, given as a fish oil supplement, induced a non-significant reduction of 22%. These findings must be considered as preliminary and warrant further research. Intake of omega-3 LC-PUFA is frequently reported to modestly increase LDL cholesterol. However, in normo- or slightly hyperlipidemic individuals who received omega-3 LC-PUFA for 4 months or longer, changes of LDL cholesterol were not significantly different from a placebo group. Both EPA and DHA lower serum triglycerides, but they may have a differential effect on lipoproteins. Intake of omega-3 LC-PUFA in the amount mentioned above is safe.