Omega-3s Lower Triglycerides

The clinical uses of omega-3 fatty acids (n-3 FAs) include treatment of hypertrglyceridaemia, use in statin-treated patients with elevated triaclyglycerol (TG) concentrations or non-HDL (high-denisty lipoprotein) cholesterol (mixed hyperlipidaemia), and use in the secondary and primary prevention of cardiovascular disease.

A recent pooled meta-analysis with multiple doses of n-3 FAs ranging from 0.8-5.4/g revealed highly significant (p<0.001) changes in TG, HDL cholesetrol and low-density lipoprotein (LDL) cholesterol (see Table 1).

Table 1: Effect of n-3 FAs on lipids
Lipids Change 95% Confidence Interval
TG -27mg/dL -33, -20
HDL Cholesterol +1.6mg/dL +.08, +2.3
LDL Cholesterol +6mg/dL +3, +8

 

Across the studies, each 1g/d increase in fish oil dose was associated with a decrease in TG of 8mg/dL.

Several meta-analyses have also been conducted to determine the degree of TG reductions seen with n-3 FAs. In a meta-analysis of 72 placebo-controlled trials, average TG reductions with fixed doses of 3-4g n-3 FAs as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) were between 25-35 %, with greater reductions seen in those with high TG concentrations of >500ml/dL.

The American Heart Association recommends regular m-3 FA intake for primary and secondary prevention of coronary heart disease (CHD), as summarised in Table 2.

 

Table 2: Amerian Heart Association recommendations for n-3 FA intake
Population Recommendation
Patients without documented coronary heart disease (CHD) Eat a variety of oily fish at least twice weekly. Include oils and foods rich in a-linolenic acid (e.g. flaxseed, walnuts)
Patients with documented CHD Consume ~1g EPA + DHA per day either from oily fish or supplementation.
Patients requiring TG-lowering 2-4g EPA + DHA per day.

 

Jacobson TA. Role of n-3 fatty acids in the treatment of hypertriglyceridemia and cardiovascular disease. Am J Clin Nutr 2008 Jun; 87(6):S1981-S1990.