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Comparison of the Effects of Fasting Glucose, Hemoglobin A1c, and Triglyceride-Glucose Index on Cardiovascular Events in Type 2 Diabetes Mellitus.
Su, WY, Chen, SC, Huang, YT, Huang, JC, Wu, PY, Hsu, WH, Lee, MY
Nutrients. 2019;11(11)
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Cardiovascular disease generally refers to the narrowing or blockage of the arteries of the heart, which can lead to a heart attack or stroke and is the major cause of death in individuals with type 2 diabetes. Identifying individuals with type 2 diabetes who are at high risk of developing cardiovascular disease could ensure better management of these patients. This retrospective observational study of 3524 individuals with type 2 diabetes aimed to investigate if the amount of sugar found in the blood over the last few months, known as haemaglobin A1c (HbA1c) can predict cardiovascular disease in individuals with type 2 diabetes. In addition, the study looked at the triglyceride-glucose (TyG) index and its relationship to cardiovascular disease outcomes. The results showed that several factors were associated with cardiovascular disease, however of main note was that the TyG index and the amount of sugar in the blood following a fast were associated with increased cardiovascular events in individuals with type 2 diabetes, but HbA1c was not. It was concluded that TyG and the blood sugar level could be used to allow early identification and management of type 2 diabetics to prevent cardiovascular events. Clinicians could use this study to justify the use of measuring the TyG index and blood sugar levels as a predictor for cardiovascular events to ensure that patients are managed not only for type 2 diabetes but also to reduce their risk of cardiovascular events in the future.
Abstract
The triglyceride-glucose (TyG) index has been correlated with insulin resistance. We aim to investigate the role of the TyG index on cardiovascular (CV) events in type 2 diabetes mellitus and compare the roles of fasting glucose, hemoglobin A1c, and the TyG index in predicting CV events. This retrospective study enrolled 3524 patients with type 2 diabetes from the Kaohsiung Medical University Research Database in 2009 in this longitudinal study and followed them until 2015. The TyG index was calculated as log (fasting triglyceride level (mg/dL) × fasting glucose level (mg/dL)/2). CV events included myocardial infarction, unstable angina, stroke, hospitalization for coronary artery disease, peripheral artery disease, and CV-related death. The association between variables and CV events was assessed using a multivariable stepwise Cox proportional hazard analysis. Two hundred and fifteen CV events (6.1%) were recorded during a follow-up period of 5.93 years. The multivariable stepwise analysis showed that high fasting glucose (HR, 1.007; p < 0.001) and a high TyG index (HR, 1.521; p = 0.004) but not hemoglobin A1c or triglycerides were associated with a higher rate of CV events. Adding fasting glucose and the TyG index to the basic model improved the predictive ability of progression to a CV event (p < 0.001 and p = 0.018, respectively), over that of hemoglobin A1c (p = 0.084) and triglyceride (p = 0.221). Fasting glucose and the TyG index are useful parameters and stronger predictive factors than hemoglobin A1c and triglyceride for CV events and may offer an additional prognostic benefit in patients with type 2 diabetes.
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A Mediterranean Diet with Fresh, Lean Pork Improves Processing Speed and Mood: Cognitive Findings from the MedPork Randomised Controlled Trial.
Wade, AT, Davis, CR, Dyer, KA, Hodgson, JM, Woodman, RJ, Keage, HAD, Murphy, KJ
Nutrients. 2019;11(7)
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Dementia is characterised by severe cognitive impairment and reduced quality of life. Observational studies have demonstrated that populations following a traditional Mediterranean diet experience less cognitive decline and a lowered risk of dementia. The aim of this study was to examine a Mediterranean diet modified to include 2–3 fresh servings of pork each week across measures of cognitive function and well-being. The study is a 24-week parallel randomised controlled crossover design to compare a Mediterranean diet with 2-3 weekly servings of fresh, lean pork (MedPork) and a low-fat control diet (LF). It recruited adults aged 45–80 years due to their increased risk of developing cardiovascular disease. Results indicate that compared with the LF control diet, the MedPork intervention led to higher performance in the cognitive domain of processing speed and higher scores for the SF-36 subscale emotional role functioning. No significant differences were observed for other domains of cognitive function, nor for additional measures of psychological well-being. Authors conclude that the MedPork intervention can improve processing speed and mood in a population at risk of cardiovascular disease and therefore dementia.
Abstract
BACKGROUND The Mediterranean diet may be capable of improving cognitive function. However, the red meat restrictions of the diet could impact long-term adherence in Western populations. The current study therefore examined the cognitive effects of a Mediterranean diet with additional red meat. METHODS A 24-week parallel crossover design compared a Mediterranean diet with 2-3 weekly servings of fresh, lean pork (MedPork) and a low-fat (LF) control diet. Thirty-five participants aged between 45 and 80 years and at risk of cardiovascular disease followed each intervention for 8 weeks, separated by an 8-week washout period. Cognitive function was assessed using the Cambridge Neuropsychological Test Automated Battery. Psychological well-being was measured through the SF-36 Health Survey and mood was measured using the Profile of Mood States (POMS). RESULTS During the MedPork intervention, participants consumed an average of 3 weekly servings of fresh pork. Compared to LF, the MedPork intervention led to higher processing speed performance (p = 0.01) and emotional role functioning (p = 0.03). No other significant differences were observed between diets. CONCLUSION Our findings indicate that a Mediterranean diet inclusive of fresh, lean pork can be adhered to by an older non-Mediterranean population while leading to positive cognitive outcomes.
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Visceral obesity, skeletal muscle mass and resistin in metabolic syndrome development.
Rodríguez-López, CP, González-Torres, MC, Cruz-Bautista, I, Nájera-Medina, O
Nutricion hospitalaria. 2019;36(1):43-50
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Obesity is a growing public health problem at a national and global level. Visceral adipose tissue (VAT) is the most bioactive component that is related with the release of inflammatory mediators which gives rise to insulin resistance, mainly local, and subsequently in liver and skeletal muscle. The aim of this study was to determine the relationship of body components with the concentration of resistin as an inflammatory marker in patients with overweight and obesity. The study is an observational, cross-sectional clinical study which analysed 40 participants with an age range between 18 and 40 years. Results indicate that: - as body mass index and VAT increased, anthropometric measurements, body composition, and biochemical indicators were altered. - persons with obesity and increased VAT had the highest proportions of metabolic syndrome (MS). - an increase in skeletal muscle is related with increased BMI and with the presence of increased VAT. - there was a significant increase in resistin concentration in individuals without MS and increased VAT compared to those without MS and normal VAT. Authors conclude that resistin might be acting as an inflammatory adipocytokine [a bioactive product produced by adipose tissue], contributing to the increase in frequency of MS in those persons who present increased levels of this cytokine.
Abstract
INTRODUCTION Background: obesity implies an increase in the visceral adipose tissue (VAT), which is a risk factor for various metabolic diseases. VAT releases proinflammatory mediators, like resistin. In addition, it has been noted that the skeletal muscle mass (SMM) is involved in the development of metabolic syndrome (MS). Objective: this study was designed to determine the relationship of body components (VAT and SMM) with MS and resistin in patients with obesity. Methods: body composition and anthropometric and biochemical measurements to assess MS, and ELISA tests for resistin were carried out in 40 patients aged 18-40 years. Results: overweight and obesity were observed in 72% of patients; visceral obesity was found in 53% and 35% had MS. A positive correlation between VAT and SMM in patients with MS was detected. In the entire population, an increase of 1 kg of SMM was found to be associated with an increase of 3 cm2 of VAT, and an increase of 4 cm2 of VAT was observed in individuals with MS. According to resistin, people with increased VAT had higher concentration than persons with normal VAT. Furthermore, an increase of 1 cm2 of VAT accounted for a person entertaining a 3.3 fold greater risk of MS for different values of SMM and resistin. Conclusion: the transcendence and significance of VAT as a main factor in triggering the chronic inflammatory process and MS, the SMM and resistin were also related. INTRODUCCIÓN: Introducción: la obesidad implica un aumento del tejido adiposo visceral (TAV), el cual es un factor de riesgo para varias enfermedades metabólicas. El VAT se relaciona con mediadores proinflamatorios, como la resistina. Además, se ha observado que la masa musculoesquelética (MME) interviene en el desarrollo del síndrome metabólico (SM). Objetivo: este estudio fue diseñado para determinar la relación de la composición corporal (TAV y MME) con el SM y la resistina en pacientes con obesidad. Métodos: se realizaron medidas antropométricas, de composición corporal y bioquímica para determinar el SM y prueba de ELISA para resistina en 40 pacientes de 18 a 40 años de edad. Resultados: se observó sobrepeso y obesidad en el 72% de los participantes, obesidad visceral en el 53% y el 35% presentó SM. Se detectó una correlación positiva entre el TAV y la MME en pacientes con SM. En el grupo de estudio encontramos que un aumento de un 1 kg de MME se asociaba con un incremento de 3 cm2 de TAV y en individuos con SM, con un incremento de 4 cm2 de TAV. En relación con la resistina, las personas con TAV incrementado presentan concentraciones más altas que las personas con TAV normal. Además, se observó que un aumento de 1 cm2 de TAV representa un riesgo 3,3 veces mayor que para las personas de padecer SM para diferentes valores de MME y de resistina. Conclusión: además de la trascendencia y la importancia del TAV como factor principal para desencadenar el proceso inflamatorio crónico y el SM, se observó que la MME y la resistina también están relacionadas.
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Health-Promoting Components in Fermented Foods: An Up-to-Date Systematic Review.
Melini, F, Melini, V, Luziatelli, F, Ficca, AG, Ruzzi, M
Nutrients. 2019;11(5)
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While fermented foods have long been produced, a renewed interest has been observed in Western countries. Several reviews have investigated the health benefits of fermented foods, however none of them have discussed the components that form upon fermentation and their possible effect on health. The purpose of this study was to provide a comprehensive review of the health-promoting components of fermentation in order to better understand their role in healthy diets. This systematic review found fermentation increased antioxidant activity of milks, cereals, fruit, vegetables, meat and fish based on 125 analysed articles. Fermentation of different food categories led to varying health benefits including vitamin content, probiotic activity and anti-hypertensive properties. Based on the existing literature, the authors conclude fermented foods should be consumed regularly and recommend they be included in worldwide dietary guidelines.
Abstract
Fermented foods have long been produced according to knowledge passed down from generation to generation and with no understanding of the potential role of the microorganism(s) involved in the process. However, the scientific and technological revolution in Western countries made fermentation turn from a household to a controlled process suitable for industrial scale production systems intended for the mass marketplace. The aim of this paper is to provide an up-to-date review of the latest studies which investigated the health-promoting components forming upon fermentation of the main food matrices, in order to contribute to understanding their important role in healthy diets and relevance in national dietary recommendations worldwide. Formation of antioxidant, bioactive, anti-hypertensive, anti-diabetic, and FODMAP-reducing components in fermented foods are mainly presented and discussed. Fermentation was found to increase antioxidant activity of milks, cereals, fruit and vegetables, meat and fish. Anti-hypertensive peptides are detected in fermented milk and cereals. Changes in vitamin content are mainly observed in fermented milk and fruits. Fermented milk and fruit juice were found to have probiotic activity. Other effects such as anti-diabetic properties, FODMAP reduction, and changes in fatty acid profile are peculiar of specific food categories.
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Vegetarian diet and blood pressure in a hospital-base study.
Liu, HW, Liu, JS, Kuo, KL
Ci ji yi xue za zhi = Tzu-chi medical journal. 2018;30(3):176-180
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High blood pressure (BP) accounts for approximately 50% of cardiovascular disease morbidity worldwide. The aim of this study was to examine the effect of a vegetarian diet on BP in participants with or without proteinuria [the earliest marker of kidney damage]. This study is a large retrospective cross-sectional study. The medical records of 36,617 individuals, 16,415 (44.8%) males and 20,202 (55.2%) females were examined. Results indicate that a vegan diet was significantly associated with lower systolic and diastolic BP compared with a nonvegetarian diet in asymptomatic participants with proteinuria. Authors conclude that a vegan diet could be an effective nonpharmacologic approach to reduce BP.
Abstract
OBJECTIVE Previous studies have reported that a vegetarian diet may lower blood pressure (BP), but the effect of diet on BP in asymptomatic participants with proteinuria is unknown. We examined the association of diet and BP in individuals with or without proteinuria. MATERIALS AND METHODS This cross-sectional study analyzed data from participants who were more than 40 years old and received physical checkups at Taipei Tzu Chi Hospital from September 5, 2005, to December 31, 2016. Diets were assessed at baseline by a self-reported questionnaire and categorized as vegan, lacto-ovo vegetarian, or omnivore. There were 2818 (7.7%) vegans, 5616 (15.3%) lacto-ovo vegetarians, and 28,183 (77.0%) omnivores. The effect of different parameters on BP was determined using a multivariate multiple linear regression model with no intercept, with control for important characteristics and lifestyle confounders. RESULTS The vegan group had a lower mean systolic BP (-3.87 mmHg, P < 0.001) and diastolic BP (-2.48 mmHg, P < 0.001) than the omnivore group. Participants with proteinuria had a higher systolic BP (4.26 mmHg, P < 0.001) and diastolic BP (2.15 mmHg, P < 0.001) than those without proteinuria. Interaction analysis indicated that vegan participants with proteinuria had a lower systolic BP (-2.73 mmHg, P = 0.046) and diastolic BP (-2.54 mmHg, P = 0.013) than other participants with proteinuria. However, individuals in the lacto-ovo group with proteinuria had a BP similar to other participants with proteinuria. CONCLUSIONS A vegan diet was associated with lower BP in asymptomatic participants with proteinuria. This diet could be a nonpharmacologic method to reduce BP.
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Systematic review of palm oil consumption and the risk of cardiovascular disease.
Ismail, SR, Maarof, SK, Siedar Ali, S, Ali, A
PloS one. 2018;13(2):e0193533
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Palm oil, the most widely consumed vegetable oil in the world, derives from the palm tree fruit with a balanced ratio of unsaturated and saturated fatty acids. Studies have shown an association between high contents of saturated fats in palm oil with the detrimental atherogenic profile. The review aims at synthesising the available evidence reporting the association of palm oil consumption with cardiovascular disease risk and cardiovascular disease-specific mortality, including specifically Coronary Heart Disease (CHD) and stroke. The authors systematically searched three databases up to June 2017 without restriction on setting or language. Published interventional and observational studies that evaluated palm oil consumption with coronary heart disease or stroke in adults were searched. Separate searches were performed depending on the outcome. The study did not find a clear association between palm oil consumption and risk or mortality of cardiovascular disease, namely coronary heart disease and stroke. The health effects found between association of palm oil consumption and risk of coronary heart disease were not unique to just palm oil consumption as other food items were also included in the analysis. The review could not establish strong evidence for or against palm oil consumption relating to cardiovascular disease risk and cardiovascular disease-specific mortality. A healthy overall diet is suggested for good cardiometabolic health.
Abstract
BACKGROUND The high amount of saturated fatty acids (SFA) coupled with the rising availability and consumption of palm oil have lead to the assumption that palm oil contributes to the increased prevalence of cardiovascular diseases worldwide. We aimed at systematically synthesising the association of palm oil consumption with cardiovascular disease risk and cardiovascular disease-specific mortality. METHODS We systematically searched Central, Medline and Embase databases up to June 2017 without restriction on setting or language. We performed separate searches based on the outcomes: coronary heart disease and stroke, using keywords related to these outcomes and palm oil. We searched for published interventional and observational studies in adults (Age: >18 years old). Two investigators extracted data and a consensus was reached with involvement of a third. Only narrative synthesis was performed for all of the studies, as the data could not be pooled. RESULTS Our search retrieved 2,738 citations for stroke with one included study and 1,777 citations for coronary heart disease (CHD) with four included studies. Palmitic acid was reported to be associated with risk of myocardial infarction (MI) (OR 2.76; 95%CI = 1.39-5.47). Total SFA intake was reported to be not significant for risk of MI. Varying intake of fried foods, highest contributor to total SFA with 36% of households using palm oil for frying, showed no significant associations to risk of MI. Odds of developing first non-fatal acute MI was higher in palm oil compared to soybean oil with 5% trans-fat (OR = 1.33; 95%CI = 1.09-1.62) than palm oil compared to soybean oil with 22% trans-fat (OR = 1.16; 95%CI = 0.86-1.56). Nevertheless, these risk estimates were non-significant and imprecise. The trend amongst those taking staple pattern diet (characterised by higher palm oil, red meat and added sugar consumption) was inconsistent across the factor score quintiles. During the years of 1980 and 1997, for every additional kilogram of palm oil consumed per-capita annually, CHD mortality risk was 68 deaths per 100,000 (95% CI = 21-115) in developing countries and 17 deaths per 100,000 (95%CI = 5.3-29) in high-income countries, whereas stroke was associated with 19 deaths per 100,000 (95%CI = -12-49) and 5.1 deaths per 100,000 (95% CI: -1.2-11) respectively. The evidence for the outcomes of this review were all graded as very low. The findings of this review should be interpreted with some caution, owing to the lack of a pooled effect estimate of the association, significant bias in selection criteria and confounding factors, inclusion of other food items together with palm oil, and the possible out-dated trend in the ecological study. CONCLUSION In view of the abundance of palm oil in the market, quantifying its true association with CVD outcomes is challenging. The present review could not establish strong evidence for or against palm oil consumption relating to cardiovascular disease risk and cardiovascular disease-specific mortality. Further studies are needed to establish the association of palm oil with CVD. A healthy overall diet should still be prioritised for good cardiometabolic health.
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Adiponectin-leptin ratio: A promising index to estimate adipose tissue dysfunction. Relation with obesity-associated cardiometabolic risk.
Frühbeck, G, Catalán, V, Rodríguez, A, Gómez-Ambrosi, J
Adipocyte. 2018;7(1):57-62
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Obesity is medically defined as a condition of abnormal or excessive fat accumulation in adipose tissue, of sufficient extent to produce adverse health consequences. Presently, adipose tissue has emerged as an extremely active endocrine organ, based on its ability to secrete a plethora of biologically active adipokines [a class of cytokine mediators that are predominantly secreted by adipose cells] such as leptin and adiponectin. Furthermore, obesity is characterized by an increase in circulating leptin concentrations, in parallel to a decrease in blood levels of adiponectin. Thus, the adiponectin/leptin ratio has been suggested as a marker of adipose tissue dysfunction. A dysfunctional adipose tissue, evidenced by a lower adiponectin/ leptin ratio, is a clear contributor to the low-grade chronic inflammation associated with metabolic syndrome. Authors conclude that this ratio is highly and negatively correlated with markers of low-grade chronic inflammation emerging as a useful estimator of obesity- and metabolic syndrome- associated cardiometabolic risk.
Abstract
Obesity is currently the most extended metabolic disturbance worldwide favoring the development of cardiometabolic alterations such as type 2 diabetes, hypertension, and dyslipidemia. Obesity and the metabolic syndrome (MS) are characterized by an increase in circulating leptin concentrations, in parallel to a decrease in blood levels of adiponectin. Consequently, the adiponectin/leptin ratio has been suggested as a maker of adipose tissue dysfunction. This emerging biomarker correlates with insulin resistance better than adiponectin or leptin alone, or even HOMA and is decreased with increasing number of metabolic risk factors having been proposed as a predictive marker for the MS. Moreover, the adiponectin/leptin ratio is negatively correlated with markers of low-grade chronic inflammation. In this sense, an increase in this ratio has been related with reduced atherosclerosis risk as well as with a decreased risk of some types of cancer in epidemiological studies. In this commentary we propose new cutoffs to estimate obesity- and MS-associated cardiometabolic risk according to the adiponectin/leptin ratio and discuss different therapeutic strategies to increase this promising biomarker of metabolic risk.
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Spices and Atherosclerosis.
Tsui, PF, Lin, CS, Ho, LJ, Lai, JH
Nutrients. 2018;10(11)
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Cardiovascular disease (CVD) is one of the leading causes of death and disability in the world. Atherosclerosis, characterised by the accumulation of fat and inflammation in blood vessels, is the main feature of CVD. Common spices such as pepper, ginger, garlic, onion, cinnamon and chilli may have effects on the initiation and development of atherosclerosis. In this review, the authors focused on the potential protective effects of spices, in atherosclerosis and CVD. Most studies to date have been carried out either in cell culture or in animals. These have revealed various potential mechanisms by which spices exert their beneficial effects, including anti-oxidant, anti-atherogenic, anti-coagulant, anti-inflammatory and cholesterol-lowering properties. There are some human studies evaluating the effects of spices on high blood pressure. Although saffron, turmeric, and chilli pepper had no effect on blood pressure, cinnamon demonstrated significant blood pressure lowering effects in patients with diabetes. Garlic has been shown to have the potential to reduce blood pressure in patients with high blood pressure. These studies provide information on the beneficial roles of spices in reducing cardiovascular risk factors. The types of spices consumed vary across cultures, and currently there are no available population studies showing that consumption of spices is associated with reduction of CVD nor any recommendations for the amounts of spices to be consumed. The authors conclude that the consumption of spices should be encouraged across countries to promote good health.
Abstract
Cardiovascular disease is one of the leading causes of death and disability in the world. Atherosclerosis, characterized by lipid accumulation and chronic inflammation in the vessel wall, is the main feature of cardiovascular disease. Although the amounts of fruits and vegetables present in the diets vary by country, diets, worldwide, contain large amounts of spices; this may have positive or negative effects on the initiation and development of atherosclerosis. In this review, we focused on the potential protective effects of specific nutrients from spices, such as pepper, ginger, garlic, onion, cinnamon and chili, in atherosclerosis and atherosclerotic cardiovascular disease. The mechanisms, epidemiological analysis, and clinical studies focusing on a variety of spices are covered in this review. Based on the integrated information, we aimed to raise specific recommendations for people with different dietary styles for the prevention of atherosclerotic cardiovascular disease through dietary habit adjustments.
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Cardio-Metabolic Benefits of Plant-Based Diets.
Kahleova, H, Levin, S, Barnard, N
Nutrients. 2017;9(8)
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Chronic disease, which includes cardiovascular disease, obesity, type 2 diabetes, hypertension, hyperlipidaemia and stroke, is the underlying cause of many health and economic burdens. There is ample evidence that proper nutrition, specifically plant-based diets (PBDs), are an effective strategy for reducing the burden of chronic disease. The aim of this narrative review is to summarise the most recent evidence on the efficacy of PBDs on various cardio-metabolic disease risk factors. This review found consistent, convincing evidence around PBDs improving body weight, glycaemic control, blood pressure and blood lipid profile, thus reducing the overall risk factors associated with chronic disease. Based on these findings, the authors conclude properly planned PBDs are an effective tool for preventing and treating cardio-metabolic disease and encourage PBDs to be recommended and promoted.
Abstract
Cardio-metabolic disease, namely ischemic heart disease, stroke, obesity, and type 2 diabetes, represent substantial health and economic burdens. Almost one half of cardio-metabolic deaths in the U.S. might be prevented through proper nutrition. Plant-based (vegetarian and vegan) diets are an effective strategy for improving nutrient intake. At the same time, they are associated with decreased all-cause mortality and decreased risk of obesity, type 2 diabetes, and coronary heart disease. Evidence suggests that plant-based diets may reduce the risk of coronary heart disease events by an estimated 40% and the risk of cerebral vascular disease events by 29%. These diets also reduce the risk of developing metabolic syndrome and type 2 diabetes by about one half. Properly planned vegetarian diets are healthful, effective for weight and glycemic control, and provide metabolic and cardiovascular benefits, including reversing atherosclerosis and decreasing blood lipids and blood pressure. The use of plant-based diets as a means of prevention and treatment of cardio-metabolic disease should be promoted through dietary guidelines and recommendations.
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Olive Polyphenols and the Metabolic Syndrome.
Saibandith, B, Spencer, JPE, Rowland, IR, Commane, DM
Molecules (Basel, Switzerland). 2017;22(7)
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Up to 25% of the world’s population has metabolic syndrome (MetS), characterised by a combination of high blood pressure, high blood sugar, obesity and abnormal levels of fats in the blood. People with MetS have an increased risk of developing type 2 diabetes and heart disease. The development of MetS is related to modifiable diet and lifestyle factors. This review presents evidence from previous studies investigating the relationship between consumption of olive products, and aspects of MetS, and discusses potential mechanisms linking olive consumption to improvements in markers of health. The authors found good evidence from previous human studies showing that the consumption of olives and olive oil lowers blood pressure in people diagnosed with high blood pressure. There is also good evidence that olives and olive oil can improve blood glucose levels in those with prediabetes and improve markers of lipid peroxidation. There is limited, but promising evidence for effects on dyslipidaemia and the inhibition of weight gain. Studies that used extra virgin olive oil (EVOO) used doses of up to 50g per day, well above the amount that is consumed habitually in most diets. Further evidence is needed to confirm the mechanisms and benefits of olive polyphenols, but the authors suggest that they may explain some of the metabolic benefits associated with a Mediterranean diet.
Abstract
Here, the effects of consuming polyphenol-rich olive products, including olive leaves, their crude extract, and extra virgin olive oil, on aspects of the metabolic syndrome are reviewed. We have sought to summarize the available scientific evidence from dietary intervention trials demonstrating a role for these phytochemicals in ameliorating aberrant glucose metabolism, high blood pressure and elevated blood lipids, and we discuss the potential mechanisms underpinning these observations. Searches for relevant literature published in English were conducted via PubMed and Science Direct. Based on published dietary intervention studies, there is convincing evidence to show that olive polyphenols, independently of olive lipids, reduce risk factors for metabolic syndrome, in particular by improving blood sugar and blood pressure control, and in reducing low density lipoprotein oxidation. There is more limited evidence to suggest that the consumption of olive polyphenols or related products can reduce body weight and visceral fat or impede weight gain, and similarly there are some limited data suggesting improved lipid profiles. There is some mechanistic data to support observations made in human volunteers, but further work is needed in this area. The consumption of olive polyphenols within the context of a healthy pattern of food intake may, in part, explain the reduced risk of metabolic disease associated with adherence to the Mediterranean diet.