RESUMO
The phenolic content of olive oil has a role in cardiovascular protection. Some clinical trial studies demonstrated that phenolic compounds of olive oil have antioxidant activity which can protect macronutrients from oxidative damages. The aim of this study was to summarize the results of clinical trials which assessed the effects of high- versus low-phenol olive oil on oxidative stress biomarkers levels. We searched Scopus, PubMed, Web of Science, Google Scholar, ProQuest, and Embase up to July 2021. Eight clinical trials which evaluated the effect of the phenolic content of olive oil on oxidized-LDL (ox-LDL), malondialdehyde (MDA), or ferric-reducing ability of plasma (FRAP) were included the meta analysis. A significant decrease was observed in ox-LDL level (WMD: -0.29 U/L; 95% CI: -0.51, -0.07) and MDA (WMD: -1.82 µmoL/L; 95% CI: -3.13, -0.50). However, after subgroup analysis for MDA, the result was not significant for not serious limitation (SMD: -0.05, 95% CI: -0.35 to 0.24), but significant for serious limitation (SMD: -3.64, 95% CI: -4.29 to -2.99). Also, no significant change was found in FRAP (WMD: 0.0 mmoL/L; 95% CI: -0.03, 0.04) level. Dose-response analysis indicated a significant linear relationship between the phenolic content of olive oil and ox-LDL. The present study showed some beneficial effects of high-phenol compared with low-phenol olive oil on ox-LDL and MDA levels. According to the meta-regression analysis along with the increasing phenolic content of olive oil, a reduction in oxidative stress biomarkers was observed.
RESUMO
The global consumer food waste (FW) estimates are mainly based on modeling data obtained from governments. However, a major data gap exists in FW at the household level, especially in developing countries. Meanwhile, the reliability of the existing data is questionable. This study aimed to quantify wheat bread waste (HBW) in Shiraz, Iran, and cross-examine the governmental HBW data. Face-to-face waste recall questionnaire interviews were conducted in 419 households from December 2018 to August 2019. A multistage sampling strategy consisting of stratification, clustering, and systematic sampling was employed. Moreover, we carried out a comprehensive document review to extract and analyze the official HBW data. The results revealed that the HBW in Shiraz is 1.80%-the waste amounts for traditional bread and non-traditional bread were 1.70% and 2.50%, respectively. The survey results were compared with the previous official data, revealing a substantial contradiction with the 30% HBW reported between 1991 and 2015. Possible reasons for this disparity are explored in this paper. Although our results cannot be generalized to other food commodities and locations, our findings suggest that considering the substantial likelihood of bias in the official data, policymakers should conduct more FW measurements and re-evaluate the accuracy of the existing data.
