Fish oil and cardiovascular disease: lipids and arterial function

n-3 Fatty acids have been shown to modify several key risk factors for card iovascular disease. However, it is not clear whether the apparent protectio n against cardiovascular disease is directly related to antiatherogenic fun ctions of these fatty acids or is mediated through their modification of th e risk factors through mechanisms not directly related to lipids. A major q uestion concerns the importance of lipid modification, which is a potent ou tcome of fish-oil supplementation. On balance, lipid modification is likely to represent a significant antiatherogenic fatter. The benefits include in creased HDL2-cholesterol concentrations, reduced triacylglycerol-rich lipop rotein concentrations, reduced postprandial lipemia, and reduced remnant co ncentrations. In contrast, LDL-cholesterol. concentrations have often been noted to rise and the potential of increased oxidizability of LDLs is poten tially adverse with lipid modification, but this potential can be overcome with vitamin E supplementation. The characteristic lipid changes and the un derlying mechanisms are reviewed. Additional benefits of fish oils include improved endothelial function and better arterial compliance (elasticity). Future trials will be needed to determine minimum effective dosages of eico sapentaenoic and docosahexaenoic acids over lengthy periods and to show car diovascular disease reduction through intervention.