Effect of ingestion of virgin olive oil on human low-density lipoprotein composition.

OBJECTIVE: To measure the incorporation of oleic acid and antioxidants (phenols and vitamin E) to low density lipoprotein (LDL) after acute and short-term ingestion of virgin olive oil. To study whether this incorporation contributes to an increase in LDL resistance to oxidation. SETTING: Department of Food and Nutrition, University of Barcelona, Spain and Department of Lipids and Cardiovascular Epidemiology, IMIM, Barcelona, Spain. SUBJECTS: Sixteen healthy volunteers aged 25-65 y. DESIGN AND INTERVENTIONS: To observe the change in the fatty acid profile, vitamin E, phenolic compounds and LDL oxidation-related variables after the postprandial phase and after daily ingestion of olive oil for one week. RESULTS: Few changes were observed in the postprandial phase. However, after a week of olive oil consumption there was an increase in oleic acid (P=0.015), vitamin E (P=0.047), phenolics (P=0.021) and lag time (P=0.000), and a decrease in the maximum amount of dienes (P=0.045) and oxidation rate (P=0.05). CONCLUSION: After ingestion of virgin olive oil, an increase in antioxidants and oleic acid in LDL was observed as well as an improvement of LDL resistance to oxidation. Our results support the idea that daily ingestion of virgin olive oil could protect LDL from oxidation. SPONSORSHIP: This study was supported by a research grant from Spain (ALI 97-1607-C02-02).

[Coronary disease protective factors: antioxidant effect of olive oil]. / Facteurs protecteurs de la maladie coronarienne: effet antioxydant de l'huile d'olive.

Alongside the French paradox, the REGICOR Study (Girona, Spain) has shown another paradox in the Mediterranean area: a high prevalence of cardiovascular risk factors with low incidence of myocardial infarction in the population of Girona, Spain. The antioxidant effects associated with olive oil consumption could explain part of this 'Mediterranean Paradox'. Virgin olive oils processed by two centrifugation phases and with low fruit ripeness have the highest levels of antioxidant content. The total content of phenolic compounds (PC) from virgin olive oil could delay LDL oxidation. The content and nature of olive oil PC have a high influence in the antioxidant capacity of an olive oil. PC from diet could bind human LDL in non-supplemented volunteers. PC from virgin olive oil could bind LDL and tyrosol is bioavailable in humans from ingestion of virgin olive oil in its natural form.

Administration of low doses of fish oil derived N-3 fatty acids to elderly subjects.

OBJECTIVES: To assess the incorporation of n-3 polyunsaturated fatty acids (PUFA) in plasma and erythrocyte lipids of elderly subjects after ingestion of very low doses of fish oil. The effects on alpha-tocopherol and retinol concentrations were also studied. SETTING: Municipal nursing home in Barcelona, Spain. SUBJECTS: Forty-five elderly subjects aged 60-92 y. DESIGN AND INTERVENTION: Subjects received a non-commercialized milk formula containing 1% fish oil for 15 months, which provided 0.40 g/d of n-3 PUFA. Fatty acid profiles and antioxidant concentrations were measured before and after the intervention period. RESULTS: Fish oil ingestion was associated with significant increases in total n-3 PUFA in plasma and erythrocytes by 32% and 18%, respectively. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid concentrations were higher after the ingestion period both in plasma and erythrocytes (P < 0.05), whereas linoleic and arachidonic acids remained unchanged. The n-6/n-3 ratio decreased by 21% in plasma and by 16% in erythrocytes (P < 0.05). Moreover, younger subjects showed a greater incorporation of EPA and DHA than older subjects. Plasma alpha-tocopherol and retinol concentrations did not vary significantly, whereas erythrocyte alpha-tocopherol was significantly higher after the intervention period. CONCLUSION: This study shows that low doses of n-3 PUFA supplemented with adequate amounts of alpha-tocopherol can be incorporated into blood lipids in elderly subjects without lowering their antioxidant concentrations.