Effects of oleic-rich and omega-3-rich diets on serum lipid pattern and lipid oxidation in mildly hypercholesterolemic patients.

AIMS

To evaluate which dietary fat elicits the best response in terms of plasma lipids, lipoproteins, and oxidative processes.

METHODS

After a 4-week run-in period, 14 mildly hypercholesterolemic subjects were fed two balanced diets for 6-week periods. During the first intervention period, patients received a monounsaturated fatty acid (MUFA)-enriched diet (olive oil diet). During the second period this diet was supplemented by n-3 polyunsaturated fatty acids (PUFAs) (n-3 diet).

RESULTS

After the olive oil diet, a significant decrease in total serum cholesterol (-8.54%, P<0.01), and in apolipoprotein B (Apo B) (-10.0%, P<0.01) was observed. With the addition of n-3 fatty acids no further significant changes in serum lipid concentrations were found. However, the n-3 diet was followed by an increase in lipoperoxides in isolated native low-density lipoprotein (LDL) (67.23%, P<0.01).

CONCLUSIONS

A beneficial effect on the serum lipid pattern was observed with the olive oil-enriched diet. The lack of further beneficial modifications on blood lipids and lipoproteins and the increase in the oxidative susceptibility of LDL observed after the addition of n-3 PUFA to the olive oil diet does not favor the use of this diet in hypercholesterolemic patients if it is not associated with a high intake of antioxidants.