Underrated aspects of a true Mediterranean diet: understanding traditional features for worldwide application of a "Planeterranean" diet.

Over the last decades, the Mediterranean diet gained enormous scientific, social, and commercial attention due to proven positive effects on health and undeniable taste that facilitated a widespread popularity. Researchers have investigated the role of Mediterranean-type dietary patterns on human health all around the world, reporting consistent findings concerning its benefits. However, what does truly define the Mediterranean diet? The myriad of dietary scores synthesizes the nutritional content of a Mediterranean-type diet, but a variety of aspects are generally unexplored when studying the adherence to this dietary pattern. Among dietary factors, the main characteristics of the Mediterranean diet, such as consumption of fruit and vegetables, olive oil, and cereals should be accompanied by other underrated features, such as the following: (i) specific reference to whole-grain consumption; (ii) considering the consumption of legumes, nuts, seeds, herbs and spices often untested when exploring the adherence to the Mediterranean diet; (iii) consumption of eggs and dairy products as common foods consumed in the Mediterranean region (irrespectively of the modern demonization of dietary fat intake). Another main feature of the Mediterranean diet includes (red) wine consumption, but more general patterns of alcohol intake are generally unmeasured, lacking specificity concerning the drinking occasion and intensity (i.e., alcohol drinking during meals). Among other underrated aspects, cooking methods are rather simple and yet extremely varied. Several underrated aspects are related to the quality of food consumed when the Mediterranean diet was first investigated: foods are locally produced, minimally processed, and preserved with more natural methods (i.e., fermentation), strongly connected with the territory with limited and controlled impact on the environment. Dietary habits are also associated with lifestyle behaviors, such as sleeping patterns, and social and cultural values, favoring commensality and frugality. In conclusion, it is rather reductive to consider the Mediterranean diet as just a pattern of food groups to be consumed decontextualized from the social and geographical background of Mediterranean culture. While the methodologies to study the Mediterranean diet have demonstrated to be useful up to date, a more holistic approach should be considered in future studies by considering the aforementioned underrated features and values to be potentially applied globally through the concept of a "Planeterranean" diet.

Association between alcoholic (poly)phenol-rich beverage consumption and cognitive status in older adults living in a Mediterranean area.

The prevalence of cognitive disorders is growing and evidence suggests the putative role of plant-based foods and beverages containing (poly)phenols. The aim of this study was to explore the association between the consumption of (poly)phenol-rich beverages, including wine and beer, resveratrol intake, and cognitive status in a cohort of older adults. The dietary intakes were assessed using a validated food frequency questionnaire, and cognitive status using the Short Portable Mental Status Questionnaire. Multivariate logistic regression analyses showed that individuals in the second and third tertile of red wine consumption were less likely to have cognitive impairment than those in the first tertile. In contrast, only individuals in the highest tertile of white wine intake were having lower odds of cognitive impairment. No significant results were found for beer intake. Individuals with higher resveratrol intake were less likely to have cognitive impairment. In conclusion, consumption of (poly)phenol-rich beverages may potentially affect cognition among older adults.

Fish and human health: an umbrella review of observational studies.

Fish represents one of the most important dietary sources of omega-3 polyunsaturated fatty acids, which are known to be associated with various health benefits. This study aimed to systematically review existing meta-analyses of observational studies exploring the association between fish intake and various health outcomes. A systematic search of electronic databases was conducted to retrieve a total of 63 studies. Evidence was deemed as possible for the association between higher fish intake and decreased risk of the acute coronary syndrome, liver cancer, and depression, and limited for other outcomes (including age-related macular degeneration, Alzheimer's disease, heart failure, all-cause and coronary heart disease mortality, total and ischaemic stroke) due to heterogeneity between results and potential otherwise inexplicable confounding factors. In conclusion, results from epidemiological studies support the mechanistic effects associated with omega-3 fatty acids from high fish consumption, but evidence needs to be further corroborated with more reliable results.

Total, red and processed meat consumption and human health: an umbrella review of observational studies.

Meat consumption has represented an important evolutionary step for humans. However, modern patterns of consumption, including excess intake, type of meat and cooking method have been the focus of attention as a potential cause of rise in non-communicable diseases. The aim of this study was to investigate the association between total, red and processed meat with health outcomes and to assess the level of evidence by performing a systematic search of meta-analyses of prospective cohort studies. Convincing evidence of the association between increased risk of (i) colorectal adenoma, lung cancer, CHD and stroke, (ii) colorectal adenoma, ovarian, prostate, renal and stomach cancers, CHD and stroke and (iii) colon and bladder cancer was found for excess intake of total, red and processed meat, respectively. Possible negative associations with other health outcomes have been reported. Excess meat consumption may be detrimental to health, with a major impact on cardiometabolic and cancer risk.

Egg consumption and cardiovascular risk: a dose-response meta-analysis of prospective cohort studies.

PURPOSE: Cardiovascular disease (CVD) is a leading cause of mortality globally and is strongly influenced by dietary risk factors. The aim was to assess the association between egg consumption and risk of CVD risk/mortality, including coronary heart disease (CHD), stroke, and heart failure. METHODS: MEDLINE, Embase, and Web of Science databases were searched through April 2020 for prospective studies. Two independent reviewers screened and extracted the data through standardized methods. Size effects were calculated as summary relative risks (SRRs) in a dose-response fashion through random-effects meta-analyses. RESULTS: Thirty-nine studies including nearly 2 million individuals and 85,053 CHD, 25,103 stroke, 7536 heart failure, and 147,124 CVD cases were included. The summary analysis including 17 datasets from 14 studies conducted on CVD (incidence and/or mortality) showed that intake of up to six eggs per week is inversely associated with CVD events, when compared to no consumption [for four eggs per week, SRR = 0.95 (95% CI: 0.90; 1.00)]; a decreased risk of CVD incidence was observed for consumption of up to one egg per day [SRR = 0.94 (95% CI: 0.89; 0.99)]. The summary analysis for CHD incidence/mortality including 24 datasets from 16 studies showed a decreased risk up to two eggs per week [(SRR = 0.96 (95% CI: 0.91; 1.00)]. No associations were retrieved with risk of stroke. The summary analysis for heart failure risk including six datasets from four studies showed that intake of one egg per day was associated with increased risk raising for higher intakes compared to no consumption [for 1 egg per day, SRR = 1.15 (95% CI:1.02; 1.30)]. After considering GRADE criteria for strength of the evidence, it was rated low for all outcomes but stroke, for which it was moderate (yet referring to no risk). CONCLUSION: There is no conclusive evidence on the role of egg in CVD risk, despite the fact that higher quality studies are warranted to obtain stronger evidence for a possible protection of CVD associated with moderate weekly egg consumption compared to no intake; equally, future studies may strengthen the evidence for increased heart failure risk associated with high regular egg consumption.

Time restricted feeding and mental health: a review of possible mechanisms on affective and cognitive disorders.

In the last decades, a high increase in life expectancy not adequately balanced by an improvement in the quality of life has been observed, leading possibly to an increase in the prevalence of affective and cognitive disorders related to aging, such as depression, cognitive impairment, dementia and Alzheimer's disease. As mental illnesses have multifactorial aetiologies, many modifiable factors including lifestyle and nutrition play an essential role. Among nutritional factors, intermittent fasting has emerged as an innovative strategy to prevent and treat mental health disorders, sleep disturbances and cognitive impairment. Among all types of intermittent fasting regimens, the time restricted feeding appears to be the most promising protocol as it allows to induce benefits of a total fasting without reducing global calories and nutrients intake. This review summarises the evidence on the effect of time restricted feeding towards brain health, emphasising its role on brain signalling, neurogenesis and synaptic plasticity.

Nut and legume consumption and human health: an umbrella review of observational studies.

Consumption of nuts and legumes has been associated with several health benefits. The aim of this study was to systematically review existing meta-analyses of observational studies on nut and legume intake and non-communicable diseases, and assess the level of evidence. Out of the six meta-analyses focussed on legume and 15 on nut intake, a possible association with decreased risk of colorectal adenoma and coronary heart disease was found for higher legume consumption, and a decreased risk of cardiovascular and cancer mortality, colon cancer, hypertension and ischaemic stroke for higher nut consumption. The association between legume consumption and cardiovascular diseases (CVDs), as well as nut consumption and risk of cancer, CVD incidence and all-cause mortality, was deemed as "limited" due to heterogeneity between results and/or potential confounding factors. General benefit towards better health can be observed for nut and legume consumption. Further studies are needed to better elucidate potential confounding factors.

Dairy foods and health: an umbrella review of observational studies.

Evidence on consumption of dairy foods and human health is contradictory. This study aimed to summarize the level of evidence of dairy consumption on various health outcomes. A systematic search for meta-analyses was performed: study design, dose-response relationship, heterogeneity and agreement of results over time, and identification of potential confounding factors were considered to assess the level of evidence. Convincing and probable evidence of decreased risk of colorectal cancer, hypertension and cardiovascular disease, elevated blood pressure and fatal stroke, respectively, was found for total dairy consumption; possible decreased risk of breast cancer, metabolic syndrome, stroke and type-2 diabetes, and increased risk of prostate cancer and Parkinson's disease was also found. Similar, yet not entirely consistent evidence for individual dairy products was reported. Among potential confounding factors, geographical localisation and fat content of dairy have been detected. In conclusions, dairy may be part of a healthy diet; however, additional studies exploring confounding factors are needed to ascertain the potential detrimental effects.

Egg consumption and human health: an umbrella review of observational studies.

Egg consumption has been an area of controversy regarding its impact on human health largely due to the content in cholesterol and its potential role in cardio-metabolic outcomes. This study aimed to summarise the level of evidence of egg consumption on various health outcomes. A systematic search for meta-analyses was performed: study design, dose-response relationship, heterogeneity and agreement of results over time, and identification of potential confounding factors were considered to assess the level of evidence. Results from this umbrella review showed a substantial no association between egg consumption and a number of health outcomes, including cancer, cardiovascular and metabolic disorders. In contrast, evidence of possible beneficial effects toward stroke risk has been found. In conclusions, egg may be part of a healthy diet; however, additional studies exploring confounding factors are needed to ascertain the potential detrimental effects.

Whole grain consumption and human health: an umbrella review of observational studies.

Whole grains have been associated with a number of health benefits. We systematically reviewed existing meta-analyses of observational studies and evaluated the level of evidence for their putative effects based on pre-selected criteria. Of the 23 included studies, we found convincing evidence of an inverse association between whole grain consumption and risk of type-2 diabetes and colorectal cancer; possible evidence of decreased risk of colon cancer and cardiovascular mortality with increased whole grain intake, as well as increased risk of prostate cancer. Limited or insufficient evidence was available for all other outcomes investigated. Overall findings are encouraging for a positive effect of whole grain consumption on certain diseases, especially highly prevalent metabolic diseases, however, uncertainty of some negative associations deserves further attention.

Fruit and vegetable consumption and health outcomes: an umbrella review of observational studies.

The aim of this study was to provide a comprehensive evaluation of current evidence on fruit and vegetable consumption and health outcomes. A systematic search for quantitative syntheses was performed. Several criteria, including study design, dose-response relationship, heterogeneity and agreement of results over time, and identification of potential confounding factors, were used to assess the level of evidence. The strongest (probable) evidence was found for cardiovascular disease protection; possible evidence for decreased risk of colon cancer, depression and pancreatic diseases was found for fruit intake; and colon and rectal cancer, hip fracture, stroke, depression and pancreatic diseases was found for vegetable intake. Suggestive and rather limited associations with other outcomes have been found. Evidence of potential confounding by sex and geographical localisation has been reported. Despite findings are consistent enough for hypothesising causation (at least for cardiovascular-related outcomes), further studies are needed to clarify the role of potential confounding factors.

Coffee, Caffeine, and Health Outcomes: An Umbrella Review.

To evaluate the associations between coffee and caffeine consumption and various health outcomes, we performed an umbrella review of the evidence from meta-analyses of observational studies and randomized controlled trials (RCTs). Of the 59 unique outcomes examined in the selected 112 meta-analyses of observational studies, coffee was associated with a probable decreased risk of breast, colorectal, colon, endometrial, and prostate cancers; cardiovascular disease and mortality; Parkinson's disease; and type-2 diabetes. Of the 14 unique outcomes examined in the 20 selected meta-analyses of observational studies, caffeine was associated with a probable decreased risk of Parkinson's disease and type-2 diabetes and an increased risk of pregnancy loss. Of the 12 unique acute outcomes examined in the selected 9 meta-analyses of RCTs, coffee was associated with a rise in serum lipids, but this result was affected by significant heterogeneity, and caffeine was associated with a rise in blood pressure. Given the spectrum of conditions studied and the robustness of many of the results, these findings indicate that coffee can be part of a healthful diet.

Hepatitis C virus eradication by direct antiviral agents improves glucose tolerance and reduces post-load insulin resistance in nondiabetic patients with genotype 1.

BACKGROUND AND AIMS: Genotype 1 chronic hepatitis C is associated with an impairment of glucose homoeostasis, especially in the advanced stages of the disease. Glucose tolerance is an independent predictor of liver-related mortality in patients with cirrhosis because of chronic hepatitis C. However, no study has demonstrated so far weather hepatitis C virus clearance affects glucose tolerance. METHODS: To this aim, we performed a prospective study assessing the effects of direct antiviral agents treatment in nondiabetic cirrhotic patients with genotypes 1a/1b and impaired glucose tolerance based on a 75-g oral glucose tolerance test. Impaired glucose tolerance was diagnosed by a 2-hour plasma glucose between 140 and 199 mg/dL. Insulin resistance was estimated by the oral glucose insulin sensitivity index, an oral glucose tolerance test-derived measure. RESULTS: After meeting the inclusion criteria, the study population included 32 outpatients (26/6 genotypes 1b/1a; age 62 ± 7.4 years; 18 males) with compensated Child-A cirrhosis. All patients achieved a sustained virological response following direct antiviral agents treatment. After viral eradication, we did not observe change in fasting plasma glucose (103.5 ± 7.1 vs 102.8 ± 7.2 mg/dL, P = .15) but 2-hour plasma glucose was reduced (165.2 ± 22.7 vs 138.5 ± 21.3 mg/dL, P < .001). Hepatitis C virus eradication led also to a significant reduction in HbA1c (6.1 ± 0.2% vs 5.7 ± 0.3%, P < .001) and post-load insulin resistance as assessed by the oral glucose insulin sensitivity index (6.92 ± 1.56 vs 9.52 ± 1.39 mg/kg/min, P < .001). These effects were observed despite no change in body mass index from baseline to follow-up (25.6 ± 4.3 vs 25.8 ± 4.4, P > .5). CONCLUSIONS: Our results indicate that hepatitis C virus eradication may early improve glucose tolerance in patients with hepatitis C virus-related cirrhosis.

Caffeinated and decaffeinated coffee consumption and melanoma risk: a dose-response meta-analysis of prospective cohort studies.

To determine the association between total, caffeinated and decaffeinated coffee consumption and melanoma risk a dose-response meta-analysis on prospective cohort studies were performed. Eligible studies were identified searching PubMed and EMBASE databases from the earliest available online indexing year to March 2017. The dose-response relationship was assessed by random-effects meta-analysis and the shape of the exposure-outcome curve was modelled linearly and using restricted cubic splines. A total of seven studies eligible for meta-analysis were identified that comprised 1,418,779 participants and 9211 melanoma cases. A linear dose-response meta-analysis showed a significant association between total coffee consumption and melanoma risk. An increase in coffee consumption of one cup per day was associated with a 3% reduction in melanoma risk (RR 0.97; 95% CI 0.95-0.99). Our findings suggest that coffee intake may be inversely associated with incidence of melanoma. Nevertheless, further studies exploring also the role of confounding factors are needed to explain the heterogeneity among studies.

Association between dietary flavonoids intake and obesity in a cohort of adults living in the Mediterranean area.

Dietary polyphenols, including flavonoids, are abundantly present in a healthy and balanced diet. Evidence for their role in preventing non-communicable diseases is emerging. We examined the association between estimated habitual intake of dietary flavonoid and obesity in a cohort study. After adjusting for potential confounding factors, inverse association between total flavonoid intake and excess weight (BMI ≥25) was found (OR = 0.66, 95% CI: 0.45, 0.99); among individual classes of flavonoids, only flavanones were inversely associated with excess body weight (OR = 0.68, 95% CI: 0.48, 0.97). However, when considering adjustment for dietary factors (adherence to the Mediterranean diet), the associations were no more significant. When considering obesity as the outcome (BMI ≥30), individuals with high intake of total flavonoids and flavonols resulted less likely to be obese (OR = 0.38, 95% CI: 0.21, 0.66 and OR = 0.63, 95% CI: 0.39, 0.99, respectively), even after adjustment for confounding factors. The results of the present study add to the current literature further evidence of the association between higher flavonoid intake and decreased body weight. Further studies are needed to confirm retrieved association.

Mediterranean diet adherence in the Mediterranean healthy eating, aging and lifestyle (MEAL) study cohort.

A decline in adherence to the Mediterranean dietary pattern has been observed over the last years. The aim of this study was to assess the level of adherence to the Mediterranean diet and possible determinants in the Mediterranean healthy Eating, Aging and Lifestyle (MEAL) study cohort. Demographic and dietary data of 1937 individuals were collected in 2014-2015 from the general population of Catania, Sicily (Italy). Food frequency questionnaires and the MEDI-LITE score were used to assess adherence to the Mediterranean diet. The score well characterised consumption of major food groups, micro- and macro-nutrients. The cohort had a general good adherence, but only a minority was highly adherent. High adherence was directly associated with education, non-smoking and physical activity and inversely with high occupational status. In conclusions, Mediterranean diet is still followed in Sicily; however, nutrition education campaigns should promote healthy traditional dietary patterns in certain groups of individuals.

Does a Mediterranean-type dietary pattern exert a cardio-protective effect outside the Mediterranean region? A review of current evidence.

Current evidence suggests a beneficial effect of the Mediterranean diet (MD) on human health. This has led to a rise in studies investigating the role of the MD in cardiovascular disease (CVD) prevention outside the region of its origin. We aimed to outline the evolving understanding of the MD and to provide an overview of adherence to MD in non-Mediterranean countries and the modulatory effects of MD on CVD biomarkers. Evidence suggest that MD may exert a protective effect on CVD via ameliorating blood lipid profile and blood pressure. A protective effect of MD was found with regard to left ventricular mass but data on carotid intima media thickness and pulse wave velocity are lacking. The paucity of data does not give a clear picture of the health effects of the MD in non-Mediterranean countries, thus larger and well-designed studies on MD outside the Mediterranean countries are warranted.

Dietary Phytoestrogen Intake is Inversely Associated with Hypertension in a Cohort of Adults Living in the Mediterranean Area.

BACKGROUND: Dietary polyphenols, including phytoestrogens are abundantly present in a balanced diet. Evidence for their role in preventing non-communicable diseases is emerging. METHODS: We examined the association between estimated habitual intakes of dietary phytoestrogens and hypertension in a cohort study. The baseline data included 1936 men and women aged 18 years and older. Intakes of total phytoestrogens, isoflavones, and lignans were calculated from validated food frequency questionnaire. Data on the polyphenols content in foods were retrieved from the Phenol-Explorer database. RESULTS: Individuals in the highest quartile of dietary phytoestrogens intake were less likely to be hypertensive (OR: 0.66, 95% CI: 0.44-0.98); moreover, the association showed a significant decreasing trend. Isoflavones and lignans were not associated with lower odds of hypertension; however, some individual compounds, such as biochanin A and pinoresinol showed an independent inverse association with hypertension. CONCLUSIONS: Dietary phytoestrogens are associated with lower likelihood of hypertension in adults living in the Mediterranean area. Future studies are needed to confirm the present findings (i.e., prospective cohort studies) and to better understand the mechanisms underlying such associations.

Dietary Polyphenol Intake and Depression: Results from the Mediterranean Healthy Eating, Lifestyle and Aging (MEAL) Study.

Background: The epidemiological evidence for a relation between dietary polyphenol intake and depression is limited. Therefore, the aim of this study was to assess the association between habitual dietary intake of total polyphenols, their classes, subclasses and individual compounds and depressive symptoms among the participants of the Mediterranean healthy Eating, Lifestyle and Aging (MEAL) study. Methods: Demographic and dietary characteristics of 1572 adults living in southern Italy were analyzed. Food frequency questionnaires and Phenol-Explorer were used to calculate habitual dietary intakes of polyphenols. The Center for Epidemiologic Studies Depression Scale (CES-D-10) was used as screening tool for depressive symptoms. Multivariate logistic regression analyses were used to test associations and were expressed as odds ratio (OR) and 95% confidence intervals (CI). Results: A total of 509 individuals reported having depressive symptoms. Based on multivariate logistic regression analyses, total polyphenol intake was not associated with depressive symptoms. After adjustment for potential confounding factors, dietary intake of phenolic acid (OR = 0.64, 95% CI: 0.44, 0.93), flavanones (OR = 0.54, 95% CI: 0.32, 0.91), and anthocyanins (OR = 0.61, 95% CI: 0.42, 0.89) showed significant inverse association with depressive symptoms, when comparing the highest with the lowest quartile. Moreover, flavanones and anthocyanins, were associated with depressive symptoms in a dose-response manner. Among individual compounds, inverse association was observed for quercetin (OR = 0.53, 95% CI: 0.32, 0.86) and naringenin (OR = 0.51, 95% CI: 0.30, 0.85), for the highest versus lowest quartile of intake. When taking into consideration the major sources of the polyphenols, only citrus fruits and wine consumption was inversely associated with depressive symptoms (Q4 vs. Q1: OR= 0.51, 95% CI: 0.35, 0.75; Q4 vs. Q1: OR = 0.53, 95% CI: 0.38, 0.74, respectively). Conclusions: Higher dietary intake of flavonoid may be inversely associated with depressive symptoms. Further studies are needed to definitively confirm these observed associations.