Obesity and the metabolic syndrome in Mediterranean countries: a hypothesis related to olive oil

In Mediterranean countries people would previously have consumed a diet with a high proportion of MUFA. Physical activity would have been intense with a low level of stress. The stearoyl-CoA desaturase (SCD1) system selected over thousands of years of this type of behavior must have adapted to a particular capacity of self regulation. Now, this pattern, called the "Mediterranean diet", has been broken and many people living by the Mediterranean consume a high quantity of calories, mainly from saturated or n-6-rich fats and the relative intake of MUFA has decreased. Simultaneously, physical activity has decreased and the pattern of stress has changed towards what is called a western lifestyle. In this new context, if people have a favorable, genetically conditioned SCD1 activity that will let them confront the new situation or else have some other compensatory mechanism, such as being keen on sport, etc, then they can prevent the appearance of some of the complications associated with the metabolic syndrome. If, on the other hand, the SCD1 pattern is genetically unfavorable for this new situation and they have a new cultural context, then they do not have the alternative compensatory mechanisms and the probability of developing the metabolic syndrome is high.     

Antioxidant capacity of the Spanish Mediterranean diet

The objective of this work was to determine the total dietary antioxidant capacity (TDAC) of the Spanish Mediterranean diet. The antioxidant capacity of plant foods and beverages included in National food consumption data was determined. TDAC of the Spanish diet was estimated at 6014 and 3549 μmol trolox equivalents by FRAP (ferric reducing antioxidant power) and ABTS (free radical-scavenging capacity) procedures, respectively. About 68% of TDAC came from beverages and 20% from fruits and vegetables, with a very low contribution from cereals. The capacity to inhibit in vitro LDL oxidation of plant foods and beverages was consistent with their antioxidant capacity. The recommended daily intakes of antioxidant vitamins, C and E, represent about 10% of TDAC. Total phenolics intake was estimated as 1171 mg gallic acid/person/day by the Folin–Ciocalteau method. TDAC may be a parameter to be considered in nutritional and epidemiological studies.     

Intervention studies on Mediterranean diet and cardiovascular risk

The traditional Mediterranean diet, as studied in the 1950s to 1960s in the South of Europe, is characterized by moderate energy intake, low animal fat, high olive oil, high cereals, high legumes, nuts and vegetables, and regular and moderate wine. A Mediterranean-type diet is being developed to mimic the traditional one and fit with present life style. While numerous epidemiological studies have supported the concept that adherence to the traditional Mediterranean diet is beneficial for health and particularly protects against cardiovascular disease, the limited number of intervention studies in this field have not yet provided major support. Nevertheless, the dietary interventions performed until now have demonstrated that adoption of a Mediterranean-type diet reduces several cardiovascular risk factors in subjects at risk (primary prevention) and/or cardiovascular events or mortality in patients after a first cardiac event (secondary prevention). Among numerous foodstuffs characterizing the Mediterranean diet, virgin olive oil has been shown to display beneficial effects on a wide range of risk factors.     

The anticancer and antiobesity effects of Mediterranean diet

Cancers have been the leading cause of death worldwide and the prevalence of obesity is also increasing in these few decades. Interestingly, there is a direct association between cancer and obesity. Each year, more than 90,000 cancer deaths are caused by obesity or overweight. The dietary pattern in Crete, referred as the traditional Mediterranean diet, is believed to confer Crete people the low mortality rates from cancers. Nevertheless, the antiobesity effect of the Mediterranean diet is less studied. Given the causal relationship between obesity and cancer, the antiobesity effect of traditional Mediterranean diet might contribute to its anticancer effects. In this regard, we will critically review the anticancer and antiobesity effects of this diet and its dietary factors. The possible mechanisms underlying these effects will also be discussed.     

Definition of the Mediterranean diet based on bioactive compounds

Antioxidant (polyphenols and carotenoids) and nonantioxidant (phytosterols) bioactive compounds and dietary fiber may have a significant role in health. The intake of these compounds is strongly linked with the high consumption of fruits, vegetables, and unrefined cereals. A whole-diet approach to these food constituents is intended to render the current definition of Mediterranean diet based on food consumption more comprehensive. The Mediterranean dietary pattern can be characterized by the following four essential dietary indicators: 1) Monounsaturated to saturated fatty acid ratio (range: 1.6 to 2.0); 2) Intake of dietary fiber (41 to 62 g/person/day); 3) Antioxidant capacity of the whole diet (3500 to 5300 trolox equivalent/person/day); 4) Phytosterols intake (370 to 555 mg/person/day). The contribution of foods and beverages to these parameters is described. Spanish National Food Consumption Data for the years 2000 and 1964 were used to quantify the lowest and highest range values. The occurrence of these indicators in the Mediterranean diet has specific characteristics and there is sufficient scientific evidence to support the beneficial health effects.     

Milk minerals and the metabolic syndrome

The prevalence of the metabolic syndrome or single components of it has dramatically risen across continents in the recent past and shows a tendency to increase in the future. The increase of these metabolic disorders was accompanied by dramatic changes in people's lifestyles, mainly less physical activity and a change in dietary habits. The consumption of fast food, convenience food and soft drinks increased, while a decline in the consumption of milk and milk products occurred. Most epidemiological studies have demonstrated a negative association between calcium and dairy consumption, and the prevalence of components of the metabolic syndrome. Diets rich in calcium or dairy products facilitated weight loss and fat loss in obese subjects or rodents and reduced weight and the regaining of fat in rodents during re-feeding after dieting. A more pronounced effect was seen if calcium was derived from dairy products. From animal and cell culture experiments a mechanism was proposed that is based mainly on dietary calcium-stimulated reduction of circulating calcitriol levels, which consequently results in a lower influx of calcium into adipocytes, leading to a metabolic state that favors catabolic over anabolic pathways. Moreover, the direct effect of calcitriol on autocrine cortisol synthesis may contribute to the weight-regulating effect of calcium. Overall, human and animal experiments have shown that dietary calcium has a slight but significantly beneficial effect on blood pressure. This was more pronounced if the calcium intake was based on milk products, which may be due to the high magnesium and potassium, and low sodium content, and to angiotensin converting enzyme-inhibiting peptides in milk products. The threshold for the minimum calcium requirement with respect to weight regulation is considered to be 800–1000 mg per day. More controlled intervention studies are needed to confirm the findings and support this hypothesis. The diversity of results indicates a complex rather than a simplistic model.     

Melatonin in Mediterranean diet,a new perspective

The health‐promoting properties of the Mediterranean diet have been attributed, at least in part, to the chemical diversity of plant foods. Among phytochemicals, polyphenols represent the paradigm of the relationship between healthy foods and reduced risk of chronic‐degenerative diseases, although, in the past few years, a new element has enriched this scenario. Melatonin, and possibly other indoleamines recently discovered in some relevant Mediterranean foods, may represent a new factor contributing to the elucidation of the protective effects of diets rich in plant products. Therefore, in synergy with polyphenols and other bioactive phytochemicals (e.g. carotenoids and glucosinolates), melatonin may contribute to maximizing the benefits of healthy dietary styles. This brief survey deals with the occurrence of melatonin in the Mediterranean diet, with an emphasis on grape products, and focuses on the biological significance of dietary melatonin, an emerging and exciting topic in the field of nutritional sciences. © 2014 Society of Chemical Industry     

Lifestyle genomics and the metabolic syndrome: A review of genetic variants that influence response to diet and exercise interventions

Metabolic syndrome (MetS) comprises a cluster of risk factors that includes central obesity, dyslipidemia, impaired glucose homeostasis and hypertension. Individuals with MetS have elevated risk of type 2 diabetes and cardiovascular disease; thus placing significant burdens on social and healthcare systems. Lifestyle interventions (comprised of diet, exercise or a combination of both) are routinely recommended as the first line of treatment for MetS. Only a proportion of people respond, and it has been assumed that psychological and social aspects primarily account for these differences. However, the etiology of MetS is multifactorial and stems, in part, on a person's genetic make-up. Numerous single nucleotide polymorphisms (SNPs) are associated with the various components of MetS, and several of these SNPs have been shown to modify a person's response to lifestyle interventions. Consequently, genetic variants can influence the extent to which a person responds to changes in diet and/or exercise. The goal of this review is to highlight SNPs reported to influence the magnitude of change in body weight, dyslipidemia, glucose homeostasis and blood pressure during lifestyle interventions aimed at improving MetS components. Knowledge regarding these genetic variants and their ability to modulate a person's response will provide additional context for improving the effectiveness of personalized lifestyle interventions that aim to reduce the risks associated with MetS.     

Nutrition in the genomics era: cardiovascular disease risk and the Mediterranean diet

The effect of dietary changes on phenotypes (i.e., plasma lipid measures, body weight and blood pressure) differs significantly between individuals. This phenomenon has been more extensively researched in relation to changes in dietary fat and plasma lipid concentrations for the prevention of cardiovascular disease (CVD) compared to other pathological conditions. Although common knowledge associates low fat diets with reductions in total and plasma LDL cholesterol, the clinical evidence shows dramatic inter-individual differences in response that are partially due to genetic factors. The discovery of the cardioprotective and other healthy properties of the Mediterranean diet has popularized the consumption of Mediterranean products such as olive oil. Molecular, clinical, and epidemiological studies have begun to shed some light about how various components of this diet may protect the cardiovascular system and to decrease the risk of other diseases such as cancer. However, it is also possible that the right combination of genetic, cultural, socioeconomic factors is needed to achieve full benefit. It has been proposed that the Mediterranean diet may be closer to the ancestral foods that were part of human development and our metabolism may have evolved to work optimally on such a diet rather than with the current diets richer in saturated fat and highly refined and processed foods. Therefore, it is possible that alleles that are associated with increase disease risk may be silenced in the presence of that more ancestral and traditional diet and lifestyle. This knowledge may provide the basis for successful public health as well individual approaches for disease prevention.     

Central obesity and the Mediterranean diet: A systematic review of intervention trials

ABSTRACT

Central obesity is associated with chronic low-grade inflammation, and is a risk factor for cardiometabolic syndrome. The Mediterranean diet pattern has a convincing evidence-base for improving cardiometabolic health. This review investigated the impact of Mediterranean diet interventions on central obesity, specifically. A systematic literature search was conducted in the MEDLINE, CINAHL, EMBASE and Cochrane library databases. Search terms included: ‘Mediterranean Diet’, ‘Mediterranean dietary pattern’, ‘central obesity’ and ‘visceral fat’. The search was limited to English language and humans ≥18 years. Eighteen articles met the eligibility criteria and reported at least one outcome measure of central obesity with Mediterranean diet intervention. Central obesity measures included waist circumference (16 studies), waist-hip ratio (5 studies) and visceral fat (2 studies). Thirteen (72%) of the studies, totaling 7186 subjects (5168 subjects assigned to a Mediterranean Diet), reported a significant reduction in central obesity with a Mediterranean-type diet. However, seven out of these 13 interventions employed energy restriction, and only three showed a statistically significant favorable effect of the Mediterranean diet relative to a control group. This systematic review highlights the potential for a Mediterranean diet intervention to reduce central obesity and in turn reduce obesity-related chronic disease risk and associated public health burden.     

Mediterranean diet improves dyslipidemia and biomarkers in chronic renal failure patients

Dyslipidemia, oxidative stress (OS) and inflammation increase the risk of cardiovascular disease in chronic renal failure (CRF) patients. The aim of this study was to evaluate the effect of nutritional advice on dyslipidemia and biomarkers in CRF patients. 40 CRF patients with dyslipidemia, hypertriglyceridemia and/or hypercholesterolemia were randomly assigned to either the control or the intervention group. The intervention group received nutritional advice adapted to a Mediterranean diet (MD). Patients were assessed at baseline (T0) and after 30 (T1), 60 (T2) and 90 (T3) days for dietary intake and biomarkers. In the intervention group compared to the control group, TG concentrations were decreased by 26% at T3 (p < 0.05), TC concentrations were diminished by 14% at T2 and by 35% at T3 (p < 0.05). A decrease in LDL-C was noted at T2 and T3 (p < 0.05). The TC/HDL-C ratio was diminished at T1, T2 and T3 (p < 0.05). The apo A-I/apo B ratio was elevated at T3 (p < 0.05). HDL-C, apo A-I, apo B concentrations and the TC/LDL-C ratio were similar in the both groups at T1, T2 and T3. Creatinine, urea, glomerular filtration rate (GFR), urate, iron and bilirubin values remained unchanged in both groups. Haemoglobin concentrations were elevated at T1 (p < 0.05). Increased albumin values were observed at T2 (p < 0.05). CRP concentrations were decreased by 29% at T1 (p < 0.05) and 40% (p < 0.01) at T3. Fibrinogen (p < 0.01) concentrations were decreased at T3. In the intervention group compared to control group (p < 0.01), TBARS values were decreased by 16% at T2 and 21% at T3 (p < 0.05). In this study, we demonstrate that the nutritional management of CRF patients before dialysis based on the MD improves food consumption, reduces dyslipidemia and protects against lipid peroxidation and inflammation, allowing patients to enter dialysis with an acceptable nutritional and cardiovascular state.     

Co-occurrence and risk assessment of mycotoxins in food and diet from Mediterranean area

The contents of 14 mycotoxins were studied in samples of different cereals and cereal products from four countries of the Mediterranean region. Two hundred and sixty-five samples from Spain, Italy, Morocco and Tunisia were analysed. Samples were extracted with matrix solid-phase dispersion (MSPD) and determined by liquid chromatography-tandem mass spectrometry with a triple quadrupole mass analyser. The percentage of total samples contaminated was 53%. The frequency of contaminated samples from Spain, Italy, Tunisia and Morocco was 33%, 52%, 96% and 50%, respectively. Nivalenol and beauvericin were the most predominant mycotoxins. This is the first international report to study the presence of several mycotoxins in different types of cereal (rice, wheat, maize, rye, barley, oat, spelt and sorghum) and cereal products (snacks, pasta, soup, biscuits and flour) from the Mediterranean area, estimate the intake of mycotoxins and evaluate the risk assessment.     

Probiotics intake and metabolic syndrome: A proposal

Probiotics are practical tools to provide the modulation of microbiota. The ingestion of food or ingredients containing anti-inflammatory activity components as probiotics should be useful in obesity control and associated co-morbidities treatment. Metabolic syndrome is a metabolic dysfunction associated with visceral obesity and insulin resistance, in which the alterations in host-microbiota interactions play an important role. Besides diet and physical activity, new strategies are necessary to control metabolic syndrome, and as consequence improving quality of life. This article revises the actual knowledge concerning probiotic intake and obesity as a proposal to control metabolic syndrome.     

The metabolic efficiency of baker's yeast in an atherogenic diet

The effect of bakery compressed yeasts in the amounts of 6 and 12 g/100 g of the ration was studied in rats. It was revealed that 12 g of yeasts per 100 g of the atherogenic ration produced a hypocholesterolemic effect. A negative effect of this amount of the yeasts was manifest in the slow growth of the rats' body mass and in an increased ratio of the kidney/body mass. The yeasts amounts used did not protect the test animals from the kidney infiltration with lipids and cholesterol; 12 g of yeasts per 100 g of the ration promoted elevation of sialic acid content in the blood plasma. Morphologic changes were observed only in the aortal wall, they were characteristic of the prelipid stage of atherosclerosis and did not depend on the yeasts amount.     

Adherence to the Mediterranean diet and healthy ageing: Current evidence,biological pathways,and future directions

Abstract

With an ever-ageing population in developed countries, healthy ageing is an emerging public health priority for securing citizens’ quality of life and minimizing healthcare associated costs. While adherence to the Mediterranean diet is associated with numerous health benefits and deterrence of age-related disorders, a comprehensive review of the current evidence to guide further public health interventions is lacking. This study systematically assessed, according to PRISMA guidelines, current evidence arising from observational studies regarding the potential impact of adherence to the Mediterranean diet on healthy ageing among elder adults. Of 509 initially retrieved unique items, 9 studies (including 2 cross-sectional and 7 prospective cohort studies) were reviewed. The reviewed evidence support that adherence to the Mediterranean diet during midlife was associated with 36%–46% greater likelihood of healthy ageing. Among the elderly, adherence to the Mediterranean diet was significantly associated with healthy ageing, while diets similar to that of the Mediterranean diet were associated with 269% greater likelihood of successful ageing and 33% reduction in mortality risk. Therefore, public health interventions aimed at promoting adherence to the Mediterranean diet, particularly among the elderly, may propagate healthy ageing and diminish the healthcare associated costs associated with age-related morbidity and mortality.