Postprandial triacylglycerolaemia: the effect of low-fat dietary treatment with and without fish oil supplementation.

OBJECTIVE

This study investigated whether a low-dose of fish oil had the ability to prevent the adverse effects associated with low-fat dietary treatment, namely elevated plasma triacylglycerol (TAG) and reduced high density lipoprotein (HDL) cholesterol concentrations.

DESIGN

Thirty-two healthy volunteers participated in the trial, which consisted of four study groups (n = 8): low-fat diet with fish oil supplementation, low-fat diet without fish oil supplementation, full-fat diet with fish oil supplementation and full-fat diet without fish oil supplementation. Low-fat dietary treatment reduced dietary energy derived from fat by at least 10% and the low-dose of fish oil provided 1 g n-3 polyunsaturated fatty acids (PUFA) daily. The postprandial response to a fat-rich test meal (0.5 g/kg pre-trial body weight) was investigated before and after 16 weeks dietary intervention.

RESULTS

Fasting plasma TAG concentrations were significantly (P < or = 0.05) reduced by fish oil supplementation and significantly (P < or = 0.05) increased by the low-fat diet alone but not significantly affected following the low-fat diet with fish oil supplementation. The postprandial TAG response was significantly (P < or = 0.05) increased following the low-fat diet with fish oil supplementation.

CONCLUSION

This study demonstrated that some of the deleterious effects of a low-fat diet, reduced concentrations of the cardioprotective HDL2 cholesterol fraction and increased fasting plasma TAG concentrations were prevented when a low dose of fish oil was provided with a low-fat diet. However postprandial triacylglycerolaemia is adversely affected when the low-fat diet was supplemented with fish oil.