Catherine Itsiopoulos

The Mediterranean diet improves hepatic steatosis and insulin sensitivity in individuals with non-alcoholic fatty liver disease

BACKGROUND & AIMS Non-alcoholic fatty liver disease (NAFLD) affects up to 30% of the population and signifies increased risk of liver fibrosis and cirrhosis, type 2 diabetes, and cardiovascular disease. Therapies are limited. Weight loss is of benefit but is difficult to maintain. We aimed at examining the effect of the Mediterranean diet (MD), a diet high in monounsaturated fatty acids, on steatosis and insulin sensitivity, using gold standard techniques. METHODS Twelve non-diabetic subjects (6 Females/6 Males) with biopsy-proven NAFLD were recruited for a randomised, cross-over 6-week dietary intervention study. All subjects undertook both the MD and a control diet, a low fat-high carbohydrate diet (LF/HCD), in random order with a 6-week wash-out period in- between. Insulin sensitivity was determined with a 3-h hyperinsulinemic-euglycemic clamp study and hepatic steatosis was assessed with localized magnetic resonance (1)H spectroscopy ((1)H-MRS). RESULTS At baseline, subjects were abdominally obese with elevated fasting concentrations of glucose, insulin, triglycerides, ALT, and GGT. Insulin sensitivity at baseline was low (M=2.7 ± 1.0 mg/kg/min(-1)). Mean weight loss was not different between the two diets (p=0.22). There was a significant relative reduction in hepatic steatosis after the MD compared with the LF/HCD: 39 ± 4% versus 7 ± 3%, as measured by (1)H-MRS (p=0.012). Insulin sensitivity improved with the MD, whereas after the LF/HCD there was no change (p=0.03 between diets). CONCLUSIONS Even without weight loss, MD reduces liver steatosis and improves insulin sensitivity in an insulin-resistant population with NAFLD, compared to current dietary advice. This diet should be further investigated in subjects with NAFLD.

The impact of whole-of-diet interventions on depression and anxiety: a systematic review of randomised controlled trials

OBJECTIVE Non-pharmacological approaches to the treatment of depression and anxiety are of increasing importance, with emerging evidence supporting a role for lifestyle factors in the development of these disorders. Observational evidence supports a relationship between habitual diet quality and depression. Less is known about the causative effects of diet on mental health outcomes. Therefore a systematic review was undertaken of randomised controlled trials of dietary interventions that used depression and/or anxiety outcomes and sought to identify characteristics of programme success. DESIGN A systematic search of the Cochrane, MEDLINE, EMBASE, CINAHL, PubMed and PyscInfo databases was conducted for articles published between April 1971 and May 2014. RESULTS Of the 1274 articles identified, seventeen met eligibility criteria and were included. All reported depression outcomes and ten reported anxiety or total mood disturbance. Compared with a control condition, almost half (47%) of the studies observed significant effects on depression scores in favour of the treatment group. The remaining studies reported a null effect. Effective dietary interventions were based on a single delivery mode, employed a dietitian and were less likely to recommend reducing red meat intake, select leaner meat products or follow a low-cholesterol diet. CONCLUSIONS Although there was a high level of heterogeneity, we found some evidence for dietary interventions improving depression outcomes. However, as only one trial specifically investigated the impact of a dietary intervention in individuals with clinical depression, appropriately powered trials that examine the effects of dietary improvement on mental health outcomes in those with clinical disorders are required.

Can the Mediterranean diet prevent prostate cancer

Prostate cancer is the second most common cancer in men worldwide. Despite the global importance of this cancer, until recently little was known about risk factors apart from the well-established factors: age, family history and country of birth. The large worldwide variation in prostate cancer risk and increased risk in migrants moving from low to high risk countries provides strong support for modifiable environmental factors. We have based our review on the findings of a systematic review undertaken by an expert panel on behalf of the World Cancer Research Fund and the American Institute for Cancer Research, and new data since then, linking identified foods and nutrients with prostate cancer. Evidence indicates that foods containing lycopene, as well as selenium and foods containing it, probably protect against prostate cancer, and excess consumption of foods or supplements containing calcium are a probable cause of this cancer. The expert panel also concluded that it is unlikely that beta-carotene (whether from foods or supplements) has a substantial effect on the risk of this cancer. A recent review on environmental factors in human prostate cancer also found that there were protective effects of vitamin E, pulses, soy foods and high plasma 1,25-dihydroxyvitamin D levels. The Mediterranean diet is abundant in foods that may protect against prostate cancer and is associated with longevity and reduced cardiovascular and cancer mortality. Compared with many Western countries Greece has lower prostate cancer mortality and Greek migrant men in Australia have retained their low risk for prostate cancer. Consumption of a traditional Mediterranean diet, rich in bioactive nutrients, may confer protection to Greek migrant men, and this dietary pattern offers a palatable alternative for prevention of this disease.

A randomised, controlled trial of a dietary intervention for adults with major depression (the "SMILES" trial): study protocol

BackgroundDespite increased investment in its recognition and treatment, depression remains a substantial health and economic burden worldwide. Current treatment strategies generally focus on biological and psychological pathways, largely neglecting the role of lifestyle. There is emerging evidence to suggest that diet and nutrition play an important role in the risk, and the genesis, of depression. However, there are limited data regarding the therapeutic impact of dietary changes on existing mental illness. Using a randomised controlled trial design, we aim to investigate the efficacy and cost-efficacy of a dietary program for the treatment of Major Depressive Episodes (MDE).Methods/DesignOne hundred and seventy six eligible participants suffering from current MDE are being randomised into a dietary intervention group or a social support group. Depression status is assessed using the Montgomery–Åsberg Depression Rating Scale (MADRS) and Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (Non Patient Edition) (SCID-I/NP). The intervention consists of 7 individual nutrition consulting sessions (of approximately 60 minutes), delivered by an Accredited Practising Dietitian (APD). Sessions commence within one week of baseline assessment. The intervention focuses on advocating a healthy diet based on the Australian Dietary Guidelines and the Dietary Guidelines for Adults in Greece. The control condition comprises a befriending protocol using the same visit schedule and length as the diet intervention. The study is being conducted at two locations in Victoria, Australia (a metropolitan and regional centre). Data collection occurs at baseline (pre-intervention), 3-months (post-intervention) and 6– months. The primary endpoint is MADRS scores at 3 months. A cost consequences analysis will determine the economic value of the intervention.DiscussionIf efficacious, this program could provide an alternative or adjunct treatment strategy for the management of this highly prevalent mental disorder; the benefits of which could extend to the management of common co-morbidities including cardiovascular disease (CVD), obesity, and type 2 diabetes.Trial registrationNCT01523561

Dietary recommendations for the prevention of depression

Background: Major depressive disorder is a common, chronic condition that imposes a substantial burden of disability globally. As current treatments are estimated to address only one-third of the disease burden of depressive disorders, there is a need for new approaches to prevent depression or to delay its progression. While in its early stages, converging evidence from laboratory, population research, and clinical trials now suggests that dietary patterns and specific dietary factors may influence the risk for depression. However, largely as a result of the recency of the nutritional psychiatry field, there are currently no dietary recommendations for depression. Aim: The aim of this paper is to provide a set of practical dietary recommendations for the prevention of depression, based on the best available current evidence, in order to inform public health and clinical recommendations. Results: Five key dietary recommendations for the prevention of depression emerged from current published evidence. These comprise: (1) follow ‘traditional’ dietary patterns, such as the Mediterranean, Norwegian, or Japanese diet; (2) increase consumption of fruits, vegetables, legumes, wholegrain cereals, nuts, and seeds; (3) include a high consumption of foods rich in omega-3 polyunsaturated fatty acids; (4) replace unhealthy foods with wholesome nutritious foods; (5) limit your intake of processed-foods, ‘fast’ foods, commercial bakery goods, and sweets. Conclusion: Although there are a number of gaps in the scientific literature to date, existing evidence suggests that a combination of healthful dietary practices may reduce the risk of developing depression. It is imperative to remain mindful of any protective effects that are likely to come from the cumulative and synergic effect of nutrients that comprise the whole-diet, rather than from the effects of individual nutrients or single foods. As the body of evidence grows from controlled intervention studies on dietary patterns and depression, these recommendations should be modified accordingly.

Experiences of patients undergoing anti-VEGF treatment for neovascular age-related macular degeneration: A systematic review

Current therapy to slow disease progression in patients with neovascular age-related macular degeneration (AMD) often entails intra-vitreal injection of an anti-vascular endothelial growth factor (VEGF) agent, that begins with a three-month loading phase of four weekly injections followed by regular monthly visits with clinician-determined re-treatment. The effects of AMD on quality of life and visual function have been extensively reported in the literature, however, less is known about the burden imposed on patients by the arduous and often indefinite treatment schedule which habitually follows a diagnosis of wet AMD. To date, no systematic review has been conducted of research investigating patients’ experiences of anti-VEGF treatment for AMD. A systematic search of the Embase, Medline, PsycINFO and PubMed electronic databases was undertaken to identify all studies between January 2004 and December 2013, published in the English language and involving human participants. A hand-search of an additional four journals was conducted. Ten articles were identified for inclusion in this review. A critical appraisal was undertaken using the Critical Appraisal Skills Programme Qualitative Research Checklist and the results synthesised to form a narrative review. Few studies to date have investigated patients’ experiences of treatment for AMD. These studies have focused primarily on patients’ experiences of the injection procedure with respect to pain and anxiety. Anticipated discomfort is often greater than actual discomfort experienced during intra-vitreal injection. However, different stages of the treatment procedure produce varying levels of patient discomfort. No one method of anaesthesia has consistently been shown to be more effective in reducing discomfort associated with treatment. Common reasons underlying patient apprehension surrounding treatment include the thought of having an injection, fear of losing eyesight and fear of the unknown. Whilst these studies have not been without their methodological limitations, they provide a platform for further exploration of the patient experience.

Plasma retinol: A novel marker for cardiovascular disease mortality in Australian adults

BACKGROUND AND AIMS Vitamin A affects inflammation and immune function and is thus a factor of interest in relation to cardiovascular disease (CVD). As vitamin A circulates in the plasma in the form of retinol, this study aims to describe the relationship between plasma retinol and the 5-year incidence of CVD mortality. METHODS AND RESULTS Community-dwelling adults (n = 441, 45% with type 2 diabetes) were recruited in Melbourne, assessed at baseline and followed for 5 years. At baseline, CVD risk factors were assessed by clinical evaluation, by personal lifestyle questionnaire and from biochemistry (plasma fasting glucose, lipids, total homocysteine, C-reactive protein, retinol and carotenoids plus the urinary albumin excretion rate over 24 h.). Dietary intake was assessed by a validated food frequency questionnaire. CVD mortality over 5-years was determined by consulting state or national registries. The majority of participants had adequate plasma retinol concentrations (≥30 μg/dL). The final Cox regression model indicated that those in the highest tertile of plasma retinol (mean ± SD) 76 ± 14 μg/dL) had a significantly lower risk of 5-year CVD mortality (hazard ratio 0.27 [95% confidence interval 0.11, 0.68], P = 0.005), an effect that was not readily explained in terms of traditional CVD risk factors or dietary intake. CONCLUSION In well-nourished older Australian adults, plasma retinol was inversely associated with CVD mortality via mechanisms apparently unrelated to established CVD risk factors and dietary intake.

A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: A randomized controlled trial (HELFIMED)

Objectives: We investigated whether a Mediterranean-style diet (MedDiet) supplemented with fish oil can improve mental health in adults suffering depression. Methods: Adults with self-reported depression were randomized to receive fortnightly food hampers and MedDiet cooking workshops for 3 months and fish oil supplements for 6 months, or attend social groups fortnightly for 3 months. Assessments at baseline, 3 and 6 months included mental health, quality of life (QoL) and dietary questionnaires, and blood samples for erythrocyte fatty acid analysis. Results: n = 152 eligible adults aged 18–65 were recruited (n = 95 completed 3-month and n = 85 completed 6-month assessments). At 3 months, the MedDiet group had a higher MedDiet score (t = 3.95, P < 0.01), consumed more vegetables (t = 3.95, P < 0.01), fruit (t = 2.10, P = 0.04), nuts (t = 2.29, P = 0.02), legumes (t = 2.41, P = 0.02) wholegrains (t = 2.63, P = 0.01), and vegetable diversity (t = 3.27, P < 0.01); less unhealthy snacks (t = −2.10, P = 0.04) and red meat/chicken (t = −2.13, P = 0.04). The MedDiet group had greater reduction in depression (t = −2.24, P = 0.03) and improved mental health QoL scores (t = 2.10, P = 0.04) at 3 months. Improved diet and mental health were sustained at 6 months. Reduced depression was correlated with an increased MedDiet score (r = −0.298, P = 0.01), nuts (r = −0.264, P = 0.01), and vegetable diversity (r = −0.303, P = 0.01). Other mental health improvements had similar correlations, most notably for increased vegetable diversity and legumes. There were some correlations between increased omega-3, decreased omega-6 and improved mental health. Discussion: This is one of the first randomized controlled trials to show that healthy dietary changes are achievable and, supplemented with fish oil, can improve mental health in people with depression.

A modified Mediterranean dietary intervention for adults with major depression: Dietary protocol and feasibility data from the SMILES trial

Background: The SMILES trial was the first randomized controlled trial (RCT) explicitly designed to evaluate a dietary intervention, conducted by qualified dietitians, for reducing depressive symptomatology in adults with clinical depression. Objectives: Here we detail the development of the prescribed diet (modified Mediterranean diet (ModiMedDiet)) for individuals with major depressive disorders (MDDs) that was designed specifically for the SMILES trial. We also present data demonstrating the extent to which this intervention achieved improvements in diet quality. Methods: The ModiMedDiet was designed using a combination of existing dietary guidelines and scientific evidence from the emerging field of nutritional psychiatric epidemiology. Sixty-seven community dwelling individuals (Melbourne, Australia) aged 18 years or over, with current poor quality diets, and MDDs were enrolled into the SMILES trial. A retention rate of 93.9 and 73.5% was observed for the dietary intervention and social support control group, respectively. The dietary intervention (ModiMedDiet) consisted of seven individual nutrition counselling sessions delivered by a qualified dietitian. The control condition comprised a social support protocol matched to the same visit schedule and length. Results: This manuscript details the first prescriptive individualized dietary intervention delivered by dietitians for adults with major depression. Significant improvements in dietary quality were observed among individuals randomized to the ModiMedDiet group. These dietary improvements were also found to be associated with changes in depressive symptoms. Discussion/Conclusion: The ModiMedDiet, a novel and individually tailored intervention designed specifically for adults with major depression, can be effectively implemented in clinical practice to manage this highly prevalent and debilitating condition. Trial registration: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12612000251820. Registered 29 February 2012

Mediterranean-type diets and inflammatory markers in patients with coronary heart disease: a systematic review and meta-analysis

The health benefits of a Mediterranean diet are thought to be mediated via its anti-inflammatory effects; however, the anti-inflammatory effect of this diet is unclear in patients who have already developed coronary heart disease (CHD). This systematic review and meta-analysis assessed the effect of Mediterranean-type diets on cytokines and adipokines in patients with CHD. An electronic search of the literature was conducted up to October 2016 using PubMed, Scopus, Web of Science, and Cochrane Library. Eleven of the 435 articles identified met eligibility criteria. Four observational studies reported significant inverse associations between Mediterranean-type diet scores and inflammatory cytokines. Five clinical trials (4 in non-Mediterranean countries) demonstrated nonsignificant reductions, and 2 trials conducted in Spain demonstrated significant reductions in C-reactive protein with a Mediterranean-type diet. Random effects meta-analysis of 4 controlled trials detected a nonsignificant difference in final mean value of C-reactive protein with Mediterranean-type diet vs low-fat diet. Despite promising findings from observational studies, this review demonstrated mostly nonsignificant effects of Mediterranean-type diet interventions on inflammatory cytokines and no effect in comparison to low-fat diets in controlled trials conducted primarily in Mediterranean populations. Therefore, randomized controlled trials of a traditional Mediterranean diet in non-Mediterranean populations and with multiple inflammatory biomarkers are needed in the high-risk CHD patient group.