Dietary Intervention Study Research Articles

Childhood adiposity, serum metabolites and breast density in young women

BackgroundChildhood adiposity is inversely associated with young adult percent dense breast volume (%DBV) and absolute dense breast volume (ADBV), which could contribute to its protective effect for breast cancer later in life. The objective of this study was to identify metabolites in childhood serum that may mediate the inverse association between childhood adiposity and young adult breast density.MethodsLongitudinal data from 182 female participants in the Dietary Intervention Study in Children (DISC) and the DISC 2006 (DISC06) Follow-Up Study were analyzed. Childhood adiposity was assessed by anthropometry at the DISC visit with serum available that occurred closest to menarche and expressed as a body mass index (BMI) z-score. Serum metabolites were measured by untargeted metabolomics using ultra-high-performance liquid chromatography–tandem mass spectrometry. %DBV and ADBV were measured by magnetic resonance imaging at the DISC06 visit when participants were 25–29 years old. Robust mixed effects linear regression was used to identify serum metabolites associated with childhood BMI z-scores and breast density, and the R package mediation was used to quantify mediation.ResultsOf the 115 metabolites associated with BMI z-scores (FDR < 0.20), 4 were significantly associated with %DBV and 6 with ADBV before, though not after, adjustment for multiple comparisons. Mediation analysis identified 2 unnamed metabolites, X-16576 and X-24588, as potential mediators of the inverse association between childhood adiposity and dense breast volume. X-16576 mediated 14% (95% confidence interval (CI) = 0.002, 0.46; P = 0.04) of the association of childhood adiposity with %DBV and 11% (95% CI = 0.01, 0.26; P = 0.02) of its association with ADBV. X-24588 also mediated 7% (95% CI = 0.001, 0.18; P = 0.05) of the association of childhood adiposity with ADBV. None of the other metabolites examined contributed to mediation of the childhood adiposity–%DBV association, though there was some support for contributions of lysine, valine and 7-methylguanine to mediation of the inverse association of childhood adiposity with ADBV.ConclusionsAdditional large longitudinal studies are needed to identify metabolites and other biomarkers that mediate the inverse association of childhood adiposity with breast density and possibly breast cancer risk.

Susceptibility of Human Plasma N-glycome to Low-Calorie and Different Weight-Maintenance Diets.

Aberrant plasma protein glycosylation is associated with a wide range of diseases, including diabetes, cardiovascular, and immunological disorders. To investigate plasma protein glycosylation alterations due to weight loss and successive weight-maintenance diets, 1850 glycomes from participants of the Diogenes study were analyzed using Ultra-High-Performance Liquid Chromatography (UHPLC). The Diogenes study is a large dietary intervention study in which participants were subjected to a low-calorie diet (LCD) followed by one of five different weight-maintenance diets in a period of 6 months. The most notable alterations of the plasma glycome were 8 weeks after the subjects engaged in the LCD; a significant increase in low-branched glycan structures, accompanied by a decrease in high-branched glycan structures. After the LCD period, there was also a significant rise in N-glycan structures with antennary fucose. Interestingly, we did not observe significant changes between different diets, and almost all effects we observed immediately after the LCD period were annulled during the weight-maintenance diets period.

What are the outcomes of dietary interventions in Heart Failure with preserved Ejection Fraction? A systematic review and meta-analysis.

To determine the efficacy of dietary interventions in Heart Failure with preserved Ejection Fraction (HFpEF). Keyword searches were performed in five bibliographic databases to identify randomized or controlled studies of dietary interventions conducted in HFpEF or mixed heart failure (HF) samples published in the English language. Studies were appraised for bias and synthesized into seven categories based on the similarity of the intervention or targeted population. The quality of the body of evidence was assessed via the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) framework. Twenty-five unique interventions were identified; 17 were considered for meta-analysis. Most studies were judged to be at high risk of bias. There was moderate-quality evidence that caloric restriction led to clinically meaningful improvements in blood pressure and body weight. There was moderate-quality evidence that carbohydrate restriction resulted in meaningful reductions in blood pressure. There was very low-quality evidence that protein supplementation improved blood pressure and body weight and moderate-quality evidence for clinically meaningful improvements in function. While some types of dietary interventions appeared to deliver clinically meaningful change in critical outcomes; the study heterogeneity and overall quality of the evidence make it difficult to make firm recommendations. Greater transparency when reporting the nutritional composition of interventions would enhance the ability to pool studies. PROSPERO CRD42019145388.

A Pilot Plant Based Dietary Intervention in MGUS and SMM Patients with Elevated BMI Is Feasible and Associated with Improvements in Metabolic and Microbiome Biomarkers of Progression

Introduction Obesity, low adiponectin, high leptin, high insulin, high IGF-1, and diets lacking plant-based foods or high in insulinemic foods are all risk factors for plasma cell disorders (PCDs). Patients (pts) with monoclonal gammopathy (MGUS) and an elevated body mass index (BMI) are twice as likely to progress from MGUS to multiple myeloma (MM). Additionally, there is gut dysbiosis in pts with PCDs, and whole food plant-based diets (WFPBDs) increase stool butyrate concentrations. Butyrate has anti-cancer (HDAC and NFkB inhibition) and anti-inflammatory (proinflammatory cytokine inhibition) properties. Prior studies show that increased relative abundance of stool butyrate producers are associated with improved outcomes in PCDs. Therefore, there is a rationale to study a dietary intervention in MGUS/smoldering MM (SMM), given the standard of care is observation despite the risk of progression. Methods Therefore, we initiated a pilot dietary intervention study (NUTRIVENTION) of a WFPBD in MGUS/SMM pts with BMI ≥25 (NCT04920084) with the primary objective of determining feasibility, as measured by weight loss (>5%) and adherence (>70%) at 12 weeks (wks). Here, we present interim results on feasibility, metabolic markers (insulin, adiponectin leptin ratio, IGF-1), microbiome (relative abundance of butyrate producers, short chain fatty acids) and secreted inflammatory biomarkers (CRP, Olink proteomics) for pts analyzed to date. The intervention, consisting of fully prepared WFPBD meals and behavioral coaching was provided by Plantable. Patients received self-selected WFPBD meals (lunch/dinner) for 12 wks, along with guidance for snacks and breakfast. Behavioral counseling was provided by health coaches and a research dietitian for 24 wks. Adherence was calculated as the percentage of kcal that were whole unprocessed plant foods out of total kcal consumed. Plasma total adiponectin, leptin, IGF-1 and insulin were measured via ELISA immunoassays. Stool samples were analyzed with 16S sequencing and gas chromatography mass spectrometry for short chain fatty acids and plasma was analyzed with the Olink Target 96 inflammation panel. We calculated the median at baseline and the median change % (median change/median at baseline) at 4 and 12 wks. Results The study has completed enrollment of 22 pts (2 dropped out within 12 wks for pt preference and were replaced), with 14 having completed the 12-wk intervention. The baseline demographics for 22 pts include median age 62 years (range 40-79), 45% male, 45% minorities (black, Hispanic, or other), 50% MGUS, 77% obese, and 27% prediabetic/diabetic. Preliminary results for clinical and correlative endpoints are provided in table 1. The study met both feasibility endpoints with 7% median BMI reduction and 90% median adherence at 12 wks as described in table 1. Metabolic markers indicate an improvement in LDL cholesterol, HgbA1c, insulin and adiponectin leptin (AL) ratio. The AL ratio is a marker of insulin resistance and higher levels imply improved insulin sensitivity, reduced BMI, and inflammation. Increased insulin, leptin, IGF-1 as well as decreased adiponectin are associated with the development of MM. Microbiome shows an improvement in the relative abundance of butyrate producers at 4 wks and stool butyrate concentrations at 12 wks. Additionally, a decrease in the branched chain fatty acids are seen. There is a decrease in the proinflammatory cytokines IL8, IL12B and TNFB, a decrease in DNER, a NOTCH1 activator and an increase in the protein FGF21 that is known to promote insulin sensitivity and downregulate hepatic IGF-1 production. Butyrate is known to inhibit the formation of proinflammatory cytokines and increase FGF21 via HDAC inhibition and inhibit NOTCH signaling. Conclusions This is the first interventional study in PCDs with mechanistic insights into risk reduction through modifiable risk factors with the potential to empower pts. Preliminary results show that a WFPBD is feasible given the BMI reduction and adherence in pts with PCDs. Our data suggests that a WFPBD improves metabolic profile (BMI, insulin resistance, AL ratio and FGF21) as well as increases stool butyrate producers and butyrate levels which in turn leads to a reduction in proinflammatory cytokines. Positive changes in metabolic, microbiome and inflammation markers are potential mechanisms by which diet may alter disease trajectory. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Nontargeted and Targeted Metabolomics Identifies Dietary Exposure Biomarkers for Navy Bean and Rice Bran Consumption in Children and Adults.

Dietary exposure biomarkers are needed for advancing knowledge on healthy foods. This study examined biomarkers for navy beans and rice bran in children and adults. Plasma, urine, stool, and study foods from dietary intervention studies were analyzed by metabolomics. A total of 38 children and 49 adults were assessed after consuming navy beans and/or rice bran for 2-, 4-, 6-, or 12 weeks. From the 138-175 metabolites modulated by diet, 11 were targeted for quantification. Trigonelline and pipecolate concentrations increased in children and adult plasma after 4 weeks compared to baseline. Increased xanthurenate (46%) was observed in children plasma after rice bran intake for 4 weeks. Study foods with navy beans had higher S-methylcysteine compared to control and supported the increased urine S-methylcysteine sulfoxide. Nontargeted metabolomics was moderately effective to identify target molecules as candidate biomarkers. Study limitations include interindividual metabolite variations before diet intervention. Validation is warranted using cross-over designs and larger sample sizes.

Metabolomics analysis of type 2 diabetes remission identifies 12 metabolites with predictive capacity: a CORDIOPREV clinical trial study

BackgroundType 2 diabetes mellitus (T2DM) is one of the most widely spread diseases, affecting around 90% of the patients with diabetes. Metabolomics has proven useful in diabetes research discovering new biomarkers to assist in therapeutical studies and elucidating pathways of interest. However, this technique has not yet been applied to a cohort of patients that have remitted from T2DM.MethodsAll patients with a newly diagnosed T2DM at baseline (n = 190) were included. An untargeted metabolomics approach was employed to identify metabolic differences between individuals who remitted (RE), and those who did not (non-RE) from T2DM, during a 5-year study of dietary intervention. The biostatistical pipeline consisted of an orthogonal projection on the latent structure discriminant analysis (O-PLS DA), a generalized linear model (GLM), a receiver operating characteristic (ROC), a DeLong test, a Cox regression, and pathway analyses.ResultsThe model identified a significant increase in 12 metabolites in the non-RE group compared to the RE group. Cox proportional hazard models, calculated using these 12 metabolites, showed that patients in the high-score tercile had significantly (p-value < 0.001) higher remission probabilities (Hazard Ratio, HR, high versus low = 2.70) than those in the lowest tercile. The predictive power of these metabolites was further studied using GLMs and ROCs. The area under the curve (AUC) of the clinical variables alone is 0.61, but this increases up to 0.72 if the 12 metabolites are considered. A DeLong test shows that this difference is statistically significant (p-value = 0.01).ConclusionsOur study identified 12 endogenous metabolites with the potential to predict T2DM remission following a dietary intervention. These metabolites, combined with clinical variables, can be used to provide, in clinical practice, a more precise therapy.Trial registrationClinicalTrials.gov, NCT00924937.

Early Life Beef Consumption Patterns Are Related to Cognitive Outcomes at 1-5 Years of Age: An Exploratory Study.

Protein, iron, zinc, and choline affect early brain development and are found in beef. The aims of this study were to describe (1) early feeding practices related to introduction of beef in the rural US west (Idaho); (2) parental perceptions of beef as a first food, and (3) associations between early beef consumption and child cognition at 1-5 years. A total of 61 children and their parents were enrolled. Parents completed a survey and a food frequency questionnaire to assess perceptions of beef and early feeding practices along with their child's dietary intake at 6-12 months. Children's cognitive function was assessed using the Bayley-4 Scales of Infant and Toddler Development (12-35 months) and the NIH Toolbox for Assessment of Neurological and Behavioral Function (NIHTB) (3-5 years). Parents introduced beef at 7.79 ± 2.65 months of age, primarily so that their children could eat what the family was eating. Higher intake of beef (r = 0.41, p = 0.02), zinc (r = 0.45, p = 0.01), and choline (r = 0.39, p = 0.03) at 6-12 months was associated with better attention and inhibitory control at 3-5 years of age. These findings support the role of beef as an early food for cognitive development, although controlled dietary intervention studies are needed.

A dietary intervention study to reduce Metabolic Syndrome risks in heart-transplanted patients

Abstract Background Since heart transplantation (HTx) has become the gold standard therapy in end-staged heart failure, many factors, including metabolic syndrome (MS), represent a burden in HTx patients. Considering key role of immunosuppressive therapy and its side effects on the appearance of MS, we focused on modifiable factors including adherence to Mediterranean Diet (MD) and improvement of dietary habits. Methods 21 heart-transplanted patients were enrolled and randomized in a control group (CG; N 10) and an intervention group (IG; N 11). During two meetings (baseline, 6-month follow-up) were administered a validated Food Frequency Questionnaire (FFQ), to assess adherence to MD, and collected clinical and anthropometric parameters, IG were additionally requested to fill a food diary. IG received personalized advices, CG received standard recommendations. Comparison between IG and CG were analyzed, differences into the IG were also assessed. Results The prevalence of MS at baseline was 46% in IG and 20% in CG. During 6-month follow-up, significant lower blood pressure values were observed (median, 25th-75th: systolic 130, 120-130 IG vs 145, 130-147 CG; p = 0.004). Seven patients of IG underwent a 12-month meeting. In this group MD scores increased significantly (7 + 1.3 vs 4 + 1.5, p = 0.001). Furthermore, significant decrease of fat mass percentage (%) (23.3 + 6.3 vs 14.8 + 10.1, p = 0.014), increase of fat free mass % (76 + 6.3 vs 85.2 + 10.1, p = 0.014) and increase of body cell mass % (50.9 + 3.8 vs 53.4 + 3.4, p = 0.031) were observed. Dietary data in IG showed significant decrease of energy from saturated fatty acids % (13.0±2.1 vs 9.6±1.5, p = 0.001), sodium (mg) (2138±359 vs 1822±417, p = 0.045), and decreasing trend for cholesterol (mg) (219±82 vs 171±59, p = 0.082). Conclusions Dietary intervention based on MD perhaps can improve MS risks in heart-transplanted patients. Further investigations may be needed to assess the fundamental role of a structured nutritional follow-up in these patients. Key messages • Personalized nutritional advices based on the MD, compared to general recommendation, can significantly improve health and quality of life in heart-transplanted patients. • A structured nutritional follow-up for heart-transplanted patients may be desirable to prevent risks of Metabolic Syndrome as a public health instrument in selected categories as these patients.

Working to Answer the Effectiveness of Nutrition in IBD: Still a Ways to Go.

The Specific Carbohydrate diet (SCD) is an exclusion diet widely popular among patients with IBD, which restricts carbohydrates and processed foods. Two recently concluded controlled studies PRODUCE (Personalized Research on Diet in Ulcerative Colitis (UC) and Crohn's Disease) and DINE-CD (The Diet to Induce Remission in Crohn's disease) confirm efficacy of SCD on symptom control but fail to demonstrate a sustained anti-inflammatory response. These dietary studies are a welcome addition to a poorly understood field of dietary management of IBD, we explore some practical challenges including trial designs, recruitment, and retention in long term dietary intervention studies. Future dietary intervention studies should, therefore, incorporate endoscopic end points to establish a true anti-inflammatory response to elimination diets, preferably with detailed multi-omics analysis to understand mechanism of action.

Network-based gut microbiome analysis in dogs

A growing number of studies in the last decade described the microbial populations in different niches of the organism thank to High-throughput DNA sequencing techniques, that are easily accessible to researchers. Furthermore, network analysis allows characterisation of bacteria that are indirectly linked to outcomes such as disease, diet and host sex through their association with other taxa. The present work on the gut microbiome follows previous research in which data were collected from 8 in-house dietary intervention studies in healthy dogs. Animals were divided according to diet and sex. The process of sample collection, storage, DNA extraction and sequencing, bioinformatic and statistical analysis followed a tailored, internally defined pipeline. The extracted DNA was prepared for sequencing of the V3 and V4 regions of the 16 rRNA gene. Correlation network analysis was performed by calculating pairwise relationships between taxa using the Sparse Correlations for Compositional Data (SparCC) algorithm. First, we identified candidate bacteria that were highly abundant in the microbial community, and second, we examined taxa that were directly related to diet and sex factors. In summary, this study underpins the network structure of the gut microbiome of dogs categorised by diet and sex and provides a better explanation for the interactions between bacteria that led to the grouping of dogs based on environmental or genetic factors. Specifically, this study has provided the basis for understanding how the bacterial community in the gut is interconnected and functions as a function of diet composition and sex. Highlights Network analysis could allow indirect association between bacteria composing the gut microbiome and outcomes, such as disease, diet and sex of the host. This research put the basis on the definition of enterotypes also in dogs, a concept already applied in humans. Positively correlated bacteria, belonging to modules could help to modulate diets and therapies for the treatment of enteropathies or gut-related pathologies linked to a dysbiosis status of the host.

Test-Retest Reliability Of Physical Activity And Sedentary Behaviors In Non-diabetic Overweight And Obese Adults

Sedentary (SED) and physical activity (PA) behaviors influence health and prevalence of chronic diseases. Activity measurements help to understand the influence of SED and PA on health and disease outcomes, but these assessments can be complex. Time spent in SED and PA intensities have different health outcomes. Accelerometers permit objective measurements under free-living conditions to capture time spent in SED, light, moderate, and vigorous PA. Knowing the reliability of PA and SED measurements within a specific research study population is important when interpreting impact of SED and PA behaviors on health and disease outcomes. PURPOSE: The purpose of this study was to evaluate test-retest reliability of average time per day in SED and light, moderate, and vigorous PA parameters in accelerometer use on 2 different 7 consecutive day periods, 12 weeks apart, in adults with elevated risk for metabolic disease. METHODS: SED and PA were measured in overweight and obese research subjects in a dietary intervention study using waist worn accelerometers (ActiGraph GT3X+) for 7 days on two occasions 12 weeks apart. Test-retest reliability coefficients of 0.6 < 0.7 were considered questionable; 0.7 < 0.8 acceptable; 0.8 < 0.9 good; and ≥ 0.9 excellent. RESULTS: A total of 22 subjects (mean ± SD; age = 45.4 ± 14.1 y; BMI = 33.9 ± 6.3 kg.m-2) completed the study. Except for average minutes in vigorous PA, test-retest correlations (p < 0.001 for all) for SED and light, moderate, and vigorous PA of varying bout durations were in the acceptable to excellent range (r = 0.744 to r = 0.924). Test-retest means and correlations for average minutes in each category were SED (493.5 ± 119.9 min, 474.9 ± 100.0 min; r = 0.88, good), light (309.7 ± 87.2 min, 31.6 ± 87.7 min; r = 0.843, good), moderate (42.8 ± 18.5 min, 41.9 ± 20.6 min; r = 0.773, acceptable), and vigorous (2.3 ± 7.6 m, 1.5 ± 3.0 m; r = -.656, questionable). CONCLUSIONS: In adults at increased risk for metabolic disease, test-retest reliability measured using accelerometry for 7 days varied across SED and PA intensity levels. Reliability was highest for SED and decreased as intensity of PA increased. Time spend in vigorous PA was the most variable between tests and reliability of this measure is questionable in this population. Supported by USDA-ARS Pulse-Crop Health Initiative 58-3060-9-040.

HOMEFOOD randomized trial—beneficial effects of 6-month nutrition therapy on body weight and physical function in older adults at risk for malnutrition after hospital discharge

Background/objectivesMalnutrition is common among older adults. Dietary intervention studies in older adults aiming to improve anthropometrics measures and physical function have been inconsistent. We aimed to investigate the effects of nutrition therapy in combination with home delivered meals and oral nutritional supplements (ONS) in community-dwelling older adults discharged from hospital.MethodsA total of 106 participants (>65 years) were randomized into the intervention group (n = 53) and into the control group (n = 53). The intervention group received individual nutrition therapy (five in person visits and three phone calls) and freely delivered energy- and protein- rich foods, while the control group received standard care. Dietary intake, anthropometrics, and short physical performance battery (SPPB) were assessed at baseline and at endpoint.ResultsEnergy intake at baseline was similar in both groups (~1500 kcal at the hospital) but there was a significant increase in energy intake and body weight in the intervention group (+919 kcal/day and 1.7 kg, P < 0.001 in both cases) during the study period, compared to a significant decrease in both measures among controls (−815 kcal/day and −3.5 kg, P < 0.001 in both cases). SPPB score increased significantly in the intervention group while no changes were observed among controls.ConclusionsMost Icelandic older adults experience substantial weight loss after hospital discharge when receiving current standard care. However, a 6-month multi-component nutrition therapy, provided by a clinical nutritionist in combination with freely delivered supplemental energy- and protein-dense foods has beneficial effects on body weight, physical function, and nutritional status.Study registrationThis study was registered at ClinicalTrials.gov (NCT03995303).

Accumulation of Sulforaphane and Alliin in Human Prostate Tissue.

Diets rich in cruciferous vegetables have been associated with a lower risk of incidence and progression of prostate cancer. Sulforaphane, an isothiocyanate derived from 4-methylsulphinylbutyl glucosinolate (glucoraphanin) that accumulates in certain of these vegetables, notably broccoli, has been implicated in their protective effects. Likewise, the consumption of garlic and its sulphur-containing compounds such as alliin have been associated with a reduction in risk of prostate cancer. In this study, we tested whether consuming glucoraphanin derived from broccoli seeds and alliin derived from garlic resulted in the occurrence of these potential bioactive compounds in the prostate, which may contribute to our understanding of the putative protective effects of these dietary components. We recruited 42 men scheduled for a trans-perineal prostate biopsy into a randomised, double-blinded, 2 × 2-factorial dietary supplement four-week intervention study, and 39 completed the study. The two active interventions were supplements providing glucoraphanin from broccoli (BroccoMax®) and alliin from garlic (Kwai Heartcare®). Following the intervention, prostate biopsy tissue was analysed for the presence of sulforaphane and its thiol conjugates and for alliin and associated metabolites. Sulforaphane occurred in significantly higher levels in the prostate tissue (both within the transition and peripheral zone) of men consuming the glucoraphanin containing supplements (p < 0.0001) compared to men not consuming these supplements. However, while alliin and alliin-derived metabolites were detected within the prostate, there was no significant difference in the concentrations of these compounds in the prostate of men consuming supplements derived from garlic compared to men not consuming these supplements.

Dietary PUFA Preferably Modify Ethanolamine-Containing Glycerophospholipids of the Human Plasma Lipidome.

The content of polyunsaturated fatty acids (PUFA) in complex lipids essentially influences their physicochemical properties and has been linked to health and disease. To investigate the incorporation of dietary PUFA in the human plasma lipidome, we quantified glycerophospholipids (GPL), sphingolipids, and sterols using electrospray ionization coupled to tandem mass spectrometry of plasma samples obtained from a dietary intervention study. Healthy individuals received foods supplemented with different vegetable oils rich in PUFA. These included sunflower, linseed, echium, and microalgae oil as sources of linoleic acid (LA; FA 18:2 n-6), alpha-linolenic acid (ALA; FA 18:3 n-3), stearidonic acid (SDA; FA 18:4 n-3), and docosahexaenoic acid (DHA; FA 22:6 n-3). While LA and ALA did not influence the species profiles of GPL, sphingolipid, and cholesteryl ester drastically, SDA and DHA were integrated primarily in ethanolamine-containing GPL. This significantly altered phosphatidylethanolamine and plasmalogen species composition, especially those with 38–40 carbons and 6 double bonds. We speculate that diets enriched with highly unsaturated FA more efficiently alter plasma GPL acyl chain composition than those containing primarily di- and tri-unsaturated FA, most likely because of their more pronounced deviation of FA composition from typical western diets.

Olive Oil Phenolics and Platelets-From Molecular Mechanisms to Human Studies.

Chronically activated, dysfunctional platelets mediate the progression of the majority of non-communicable diseases in a pleiotropic fashion. Antiplatelet therapy remains an attractive therapeutic means which however hasn't reached the expected targets according to the promising preclinical studies. It is therefore obvious that the consumption of foods demonstrating antiplatelet activity may be a less drastic but on the other hand a more sustainable way of achieving daily antiplatelet therapy, either alone or in combination with antiplatelet drugs. Olive oil is probably the main cardioprotective component of the Mediterranean Diet according to the results of observational and dietary intervention studies. Among all phytochemicals of olive oil, its unique phenolics seems to be responsible for the majority of its cardioprotective properties. This review article aims to highlight the platelet modulating roles of olive oil polyphenols, trying to critically assess whether those properties could partially explain the cardioprotective role of olive oil. The cellular and animal studies clearly show that extra virging olive oil (EVOO) phenolics, mainly hydroxytyrosol, are able to inhibit the activation of platelets induced by several endogenous agonists and pathologies. However, the outcomes of the pre-clinical studies are difficult to be translated to humans mainly because the dosages and the chemical forms of the phenolics used to these studies are much higher and different to that found in human circulation. Despite the heterogeneity of the few human trials on the field so far, the results are promising showing that EVOO can exert antiplatelet actions in real, acute or long-term, trials and at least part of this antiplatelet action can be attributed to the phenolic content of EVOOs. Although we clearly need better, well-powered studies to give certain answers on this field the antiplatelet properties of olive oil phenolics is a promising, emerging mechanism which may explain some of the health properties of EVOO and the Mediterranean Diet.

Improved Aerobic Capacity and Adipokine Profile Together with Weight Loss Improve Glycemic Control without Changes in Skeletal Muscle GLUT-4 Gene Expression in Middle-Aged Subjects with Impaired Glucose Tolerance.

(1) Objective: The aim of this study was to clarify the role of adipokines in the regulation of glucose metabolism in middle-aged obese subjects with impaired glucose tolerance in response to a long-term exercise and dietary intervention. (2) Methods: Skeletal muscle, plasma and serum samples were examined in 22 subjects from an exercise–diet intervention study aiming to prevent type 2 diabetes. The subjects were further divided into two subgroups (non-responders n = 9 and responders n = 13) based on their achievement in losing at least 3 kg. (3) Results: The two-year exercise–diet intervention reduced leptin levels and increased adiponectin levels in responders; the changes in leptin levels were significantly associated with changes in their weights (r = 0.662, p < 0.01). In responders, insulin sensitivity (Bennett and McAuley index) increased and was associated with changes in maximal oxygen uptake (VO2peak) (r = 0.831, p < 0.010 and r = 0.890, p < 0.01). In addition, the VO2peak and oxidative capacity of skeletal muscle improved in responders, but not in non-responders. However, there were no changes between the two groups in expressions of the glucose transporter protein-4 (GLUT-4) gene or of AMP-activated protein kinase (AMPK)-α1 or AMPK-α2 proteins. (4) Conclusions: The exercise–diet intervention decreased serum leptin and increased serum adiponectin concentrations, improved glucose control without affecting GLUT-4 gene expression in the skeletal muscle in responders.

Characterization and Comparison of the Divergent Metabolic Consequences of High-Sugar and High-Fat Diets in Male Wistar Rats.

Diet-induced obesity (DIO) in laboratory rodents can serve as a model with which to study the pathophysiology of obesity, but obesogenic diets (high-sugar and/or high-fat) are often poorly characterised and simplistically aimed at inducing metabolic derangements for the purpose of testing the therapeutic capacity of natural products and other bioactive compounds. Consequently, our understanding of the divergent metabolic responses to different obesogenic diet formulations is limited. The aim of the present study was to characterise and compare differences in the metabolic responses induced by low-fat, medium-fat/high-sugar and high-fat diets in rats through multivariate statistical modelling. Young male Wistar rats were randomly assigned to CON (laboratory chow, low-fat), OB1 (high-sugar, medium-fat) or OB2 (high-fat) dietary groups (n = 24 each) for 17 weeks, after which metabolic responses were characterised. Projection-based multivariate analyses (principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA)) were used to explore the associations between measures of body composition and metabolism. Furthermore, we conducted a systematic literature survey to examine reporting trends in rat dietary intervention studies, and to determine how the metabolic responses observed in the present study compared to other recently published studies. The OB1 and OB2 dietary regimens resulted in distinct metabolic profiles, with OB1 characterised by perturbations in insulin homeostasis and adipose tissue secretory function, while OB2 was characterised by altered lipid and liver metabolism. This work therefore confirms, by means of direct comparison, that differences in dietary composition have a profound impact on metabolic and pathophysiological outcomes in rodent models of DIO. However, through our literature survey we demonstrate that dietary composition is not reported in the majority of rat dietary intervention studies, suggesting that the impact of dietary composition is often not considered during study design or data interpretation. This hampers the usefulness of such studies to provide enhanced mechanistic insights into DIO, and also limits the translatability of such studies within the context of human obesity.

Eating Habits among US Firefighters and Association with Cardiometabolic Outcomes.

Cardiovascular disease is the leading cause of on-duty mortality among firefighters, with obesity as an important risk factor. However, little is known regarding the dietary patterns which are characteristic in this population and how these patterns relate to cardiometabolic outcomes. The aim of this study was to identify the dietary patterns of US firefighters and examine their association with cardiometabolic outcomes. The participants (n = 413) were from the Indianapolis Fire Department, and were recruited for a Federal Emergency Management Agency (FEMA)-sponsored Mediterranean diet intervention study. All of the participants underwent physical and medical examinations, routine laboratory tests, resting electrocardiograms, and maximal treadmill exercise testing. A comprehensive food frequency questionnaire was administered, and dietary patterns were derived using principal component analysis. The mean body mass index (BMI) was 30.0 ± 4.5 kg/m2 and the percentage of body fat was 28.1 ± 6.6%. Using principal component analysis, two dietary patterns were identified, namely a Mediterranean diet and a Standard American diet. Following the adjustment for gender, BMI, maximal oxygen consumption (VO2 max), max metabolic equivalents (METS), age, and body fat percent, the Mediterranean diet was positively associated with high-density lipoprotein (HDL) cholesterol (β = 1.20, p = 0.036) in linear regression models. The Standard American diet was associated with an increase in low-density lipoprotein (LDL) cholesterol (β = −3.76, p = 0.022). In conclusion, the Mediterranean diet was associated with more favorable cardiometabolic profiles, whereas the Standard American diet had an inverse association. These findings could help in providing adequate nutrition recommendations for US firefighters to improve their health.

Diverging metabolic effects of 2 energy-restricted diets differing in nutrient quality: a 12-week randomized controlled trial in subjects with abdominal obesity

ABSTRACTBackgroundDespite the established relation between energy restriction (ER) and metabolic health, the most beneficial nutrient composition of a weight-loss diet is still a subject of debate.ObjectivesThe aim of the study was to examine the additional effects of nutrient quality on top of ER.MethodsA parallel-designed, 12-week 25% ER dietary intervention study was conducted (clinicaltrials.gov: NCT02194504). Participants aged 40–70 years with abdominal obesity were randomized over 3 groups: a 25% ER high-nutrient-quality diet (n = 40); a 25% ER low-nutrient-quality diet (n = 40); or a habitual diet (n = 30). Both ER diets were nutritionally adequate, and the high-nutrient-quality ER diet was enriched in MUFAs, n-3 PUFAs, fiber, and plant protein and reduced in fructose. Before and after the intervention, intrahepatic lipids, body fat distribution, fasting and postprandial responses to a mixed-meal shake challenge test of cardiometabolic risk factors, lipoproteins, vascular measurements, and adipose tissue transcriptome were assessed.ResultsThe high-nutrient-quality ER diet (−8.4 ± 3.2) induced 2.1 kg more weight loss (P = 0.007) than the low-nutrient-quality ER diet (−6.3 ± 3.9), reduced fasting serum total cholesterol (P = 0.014) and plasma triglycerides (P < 0.001), promoted an antiatherogenic lipoprotein profile, and induced a more pronounced decrease in adipose tissue gene expression of energy metabolism pathways than the low-quality ER diet. Explorative analyses showed that the difference in weight loss between the two ER diets was specifically present in insulin-sensitive subjects (HOMA-IR ≤ 2.5), in whom the high-nutrient-quality diet induced 3.9 kg more weight loss than the low-nutrient-quality diet.ConclusionsA high-nutrient-quality 25% ER diet is more beneficial for cardiometabolic health than a low-nutrient-quality 25% ER diet. Overweight, insulin-sensitive subjects may benefit more from a high- than a low-nutrient-quality ER diet with respect to weight loss, due to potential attenuation of glucose-induced lipid synthesis in adipose tissue.

Vegetarianism, microbiota, and cardiovascular health: looking back, and forward

Cardiovascular diseases (CVDs) are the leading cause of death globally, with over 17.9 million attributed deaths in 2019. Unhealthy diet is an often-overlooked major modifiable risk factor for CVD. Global Burden of Disease (GBD) estimates suggest that unhealthy diets account for nearly 26% of all deaths, of which 84% were attributed to CVD. Plant-based diets (PBDs), which are a diverse group of dietary patterns focused on plant produce, with flexibility for varying levels of vegetarianism, have been suggested to decrease the incidence of various cardiovascular and cardiometabolic diseases. In this review, we aim to delve into the spectrum of PBDs, revisit objective definitions and classifications, and compare them with standard non-vegetarian diets. We examine plausible mechanisms underlying the cardiovascular benefits of PBDs with a particular focus on the dietary manipulation of gut microbiota-host interaction and its effect on energy metabolism, and local and systemic inflammation. In addition, we explore the evidence on the impact of PBDs on CVD, examine the challenges and limitations associated with dietary intervention studies, and devise strategies to draw valid conclusions. Dietary interventions, such as PBDs are one of the most powerful, attainable, cost-effective tools for health and environmental protection at the population level. We conclude with a clear appreciation for PBDs in environmental sustainability, climate change, and animal welfare.