# Hydroxyryrosol-Rich Olive Extract for Plasma Cholesterol Control
## 4 Discussion
Furthermore, olive oil intake is hardly predictable because it is a seasoning, not a food, and its antioxidant effect is variably impaired by the exposition of it at cooking temperature. It should also be taken into account that olive oil is a source of lipids, so the recommended daily amount of olive oil in weight-management programs should be less than that which is recommended for the maintenance of CV health in normal-weight individuals [28]. Last but not least, not everyone likes the taste of olive oil and, of consequence, not everyone is able to adhere to a Mediterranean dietary pattern on the long-term. For all of these reasons, an olive-derived extract that is standardized in hydroxytyrosol to be consumed on top of Mediterranean diet could be of particular interest, taking into consideration that olive oil's supposed beneficial effects on the vascular and metabolic parameters depend only on its polyphenolic fraction and not MUFA. According to our observations, 100 mg olive-derived extracts that are standardized in hydroxytyrosol are able to yield a broad-spectrum of activity with significant improvement in SBP, PP, FPG, TC, HDL-C, LDL-C, non-HDL-C, and SUA after one month of its dietary supplementation. Previously, evidence from clinical trials had been mostly limited to highly selected demographic groups such as elderly people who were either free-living or living in protective residences [29; 30]. A randomized, double-blind, placebo-controlled, clinical study had already showed that one-year consumption of a polyphenol extract from _Olea europaea_ improved the lipid profile of postmenopausal women (pre-post treatment changes: TC = \(-\)26.2 mg/dL in the active group, \(p\) = 0.01 versus placebo; LDL-C = \(-\)34.7 mg/dL in the active group, \(p\) =0.02 versus placebo; TG = \(-\)4.15 mg/dL in the active group, \(p\) = 0.01 versus placebo) [29]. Another randomized, double-blind, clinical study involving institutional individuals that were aged 65-96 years had already revealed that a nutritional intervention testing a 6-week daily dietary supplementation with virgin oil improved the antioxidant status in the elderly by reducing the serum lipid levels, the serum total antioxidant capacity (TAC), and the superoxide dismutase (SOD) and glutathione peroxidase (GH-PX) activity, and by increasing the catalase (CAT) in the erythrocytes [30]. Most recently, the lipid-lowering effect of dietary supplementation with phenolic-rich olive extract has been investigated as it is associated with red yeast rice. In this context, a nutraceutical compound containing red yeast rice and olive fruit extract that is highly concentrated in hydroxytyrosol (5 mg hydroxytyrosol equivalent) has been found to be effective in reducing the serum lipid levels and also well tolerated by hypercholesterolemia patients with a history of statin-associated muscle symptoms (SAMS) [31]. Another randomized, double-blind, placebo-controlled, clinical study has showed that a food supplement combining red yeast rice and olive fruit extract (for a daily intake of 10.82 mg of monacolins and 9.32 mg of hydroxytyrosol) was able to exert beneficial effects in patients with MetS even in the short term by lowering the LDL-C by 24% (+1% in the placebo group) and also improving the TC(\(-17\%\) versus \(+2\%\) in the control group), apolipoprotein B (\(-15\%\) versus \(+6\%\), \(p<0.001\)), TG (\(-9\%\) versus \(+16\%\), \(p=0.02\)), oxidized LDL (\(-20\%\) versus \(+5\%\) in the control group. \(p<0.001\)), SBP (mean difference versus placebo \(=-0.3\) mmHg, \(p=0.001\)), and DBP (mean difference versus placebo \(=-0.4\) mmHg, \(p=0.05\)) after only 6 weeks of dietary supplementation taking place [32]. In effect, the preclinical evidence suggests that olive polyphenols are able to partially inhibit the activity of 3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA) reductase and acetyl-Coenzyme A cholesterol acyltransferase (ACAT), thus resulting in a decreased cholesterol biosynthesis [33].