Health effects of 100% fruit and vegetable juices: evidence from human subject intervention studies.

The health effects of 100% fruit and vegetable juices (FVJ) represent a controversial topic. FVJ contain notable amounts of free sugars, but also vitamins, minerals, and secondary compounds with proven biological activities like (poly)phenols and carotenoids. The review aimed to shed light on the potential impact of 100% FVJ on human subject health, comprehensively assessing the role each type of juice may have in specific health outcomes for a particular target population, as reported in dietary interventions. The effects of a wide range of FVJ (orange, grapefruit, mandarin, lemon, apple, white, red, and Concord grapes, pomegranate, cranberry, chokeberry, blueberry, other minor berries, sweet and tart cherry, plum, tomato, carrot, beetroot, and watermelon, among others) were evaluated on a series of outcomes (anthropometric parameters, body composition, blood pressure and vascular function, lipid profile, glucose homeostasis, biomarkers of inflammation and oxidative stress, cognitive function, exercise performance, gut microbiota composition and bacterial infections), providing a thorough picture of the contribution of each FVJ to a health outcome. Some juices demonstrated their ability to exert potential preventive effects on some outcomes while others on other health outcomes, emphasising how the differential composition in bioactive compounds defines juice effects. Research gaps and future prospects were discussed. Although 100% FVJ appear to have beneficial effects on some cardiometabolic health outcomes, cognition and exercise performance, or neutral effects on anthropometric parameters and body composition, further efforts are needed to better understand the impact of 100% FVJ on human subject health.

Changes in the consumption of foods characterising the Mediterranean dietary pattern and major correlates during the COVID-19 confinement in Italy: results from two cohort studies.

We investigated the effect of confinement during the COVID-19 pandemic on the consumption of foods characterising the Mediterranean dietary pattern (MDP) and its major correlates in two Italian population-based cohorts comprising 3161 subjects (mean age 57.7 ± 15.4 y). At population level, 38.8% of participants reported an improvement of diet quality during the first nationwide lockdown. Healthful dietary changes were associated with older age (ß = 0.41; 95% confidence interval [CI] 0.08, 0.73 for 56-65 vs. 18-39 y), greater wealth (ß = 0.45; 0.01, 0.89 for >40,000 ≤ 60,000 vs. ≤ 10,000 EUR/y), increased physical activity (ß = 0.52; 0.22, 0.81) and reduced body weight (ß = 0.36; 0.11, 0.62). Switching to healthy eating was also related to increased consumption of organic (ß = 1.24; 0.88, 1.60) and locally-grown food (ß = 0.74; 0.51, 0.96). The first Italian lockdown led, in a substantial part of the population, to higher intake of foods characterising a MDP; this was also accompanied by healthier lifestyle and more sustainable food choices.

Factors driving the inter-individual variability in the metabolism and bioavailability of (poly)phenolic metabolites: A systematic review of human studies.

This systematic review provides an overview of the available evidence on the inter-individual variability (IIV) in the absorption, distribution, metabolism, and excretion (ADME) of phenolic metabolites and its determinants. Human studies were included investigating the metabolism and bioavailability of (poly)phenols and reporting IIV. One hundred fifty-three studies met the inclusion criteria. Inter-individual differences were mainly related to gut microbiota composition and activity but also to genetic polymorphisms, age, sex, ethnicity, BMI, (patho)physiological status, and physical activity, depending on the (poly)phenol sub-class considered. Most of the IIV has been poorly characterised. Two major types of IIV were observed. One resulted in metabolite gradients that can be further classified into high and low excretors, as seen for all flavonoids, phenolic acids, prenylflavonoids, alkylresorcinols, and hydroxytyrosol. The other type of IIV is based on clusters of individuals defined by qualitative differences (producers vs. non-producers), as for ellagitannins (urolithins), isoflavones (equol and O-DMA), resveratrol (lunularin), and preliminarily for avenanthramides (dihydro-avenanthramides), or by quali-quantitative metabotypes characterized by different proportions of specific metabolites, as for flavan-3-ols, flavanones, and even isoflavones. Future works are needed to shed light on current open issues limiting our understanding of this phenomenon that likely conditions the health effects of dietary (poly)phenols.

Are (poly)phenols contained in 100% fruit juices mediating their effects on cardiometabolic risk factors? A meta-regression analysis.

Background: The consumption of 100% fruit juices has not been associated with substantial detrimental outcomes in population studies and may even contribute to improving the cardiometabolic profile if included in a healthy balanced diet. The main contributors to such potential beneficial effects include vitamins, minerals, and likely the (poly)phenol content. This study aimed to investigate whether the (poly)phenols contained in 100% fruit juices may mediate their effects on cardiometabolic risk factors based on published randomized controlled trials (RCT). Methods: A systematic search in PubMed/MEDLINE and Embase, updated till the end of October 2022, was carried out to identify RCT providing quantitative data on (poly)phenol content in 100% fruit juices and used as an intervention to improve cardiometabolic parameters such as blood lipids, glucose, and blood pressure. Meta-regression analysis was performed to calculate the effect of the intervention [expressed as standardized mean difference and 95% confidence intervals (CI)] using the (poly)phenol content as moderator. Results: A total of 39 articles on RCT investigating the effects of 100% fruit juices on cardiometabolic risk factors reporting data on total (poly)phenol and anthocyanin content were included in the analysis. Total (poly)phenol content was substantially unrelated to any outcome investigated. In contrast, each 100 mg per day increase in anthocyanins was related to 1.53 mg/dL decrease in total cholesterol (95% CI, -2.83, -0.22, p = 0.022) and 1.94 mg/dL decrease in LDL cholesterol (95% CI, -3.46, -0.42, p = 0.012). No other potential mediating effects of anthocyanins on blood triglycerides, glucose, systolic and diastolic pressure were found, while a lowering effect on HDL cholesterol after excluding one outlier study was observed. Discussion: In conclusion, the present study showed that anthocyanins may mediate the potential beneficial effects of some 100% fruit juices on some blood lipids. Increasing the content of anthocyanins through specific fruit varieties or plant breeding could enhance the health benefits of 100% fruit juices.

(Poly)phenolic compounds and gut microbiome: new opportunities for personalized nutrition.

For decades, (poly)phenols have been linked to cardiometabolic health, but population heterogeneity limits their apparent efficacy and the development of tailored, practical protocols in dietary interventions. This heterogeneity is likely determined by the existence of different metabotypes, sub-populations of individuals metabolizing some classes of (poly)phenols differently. The gut microbiota plays a major role in this process. The impact of microbiota-related phenolic metabotypes on cardiometabolic health is becoming evident, although the picture is still incomplete, and data are absent for some classes of (poly)phenols. The lack of a complete understanding of the main microbial actors involved in the process complicates the picture. Elucidation of the mechanisms behind phenolic metabotypes requires novel experimental designs that can dissect the inter-individual variability. This paper, in addition to providing an overview on the current state-of-the-art, proposes wider metabotyping approaches as a means of paving the way towards effective personalized nutrition with dietary (poly)phenols.

Impact of Nationwide Lockdowns Resulting from the First Wave of the COVID-19 Pandemic on Food Intake, Eating Behaviors, and Diet Quality: A Systematic Review.

The lockdowns resulting from the first wave of the coronavirus disease 2019 (COVID-19) pandemic impacted deeply on all life activities, including diet. We performed a systematic review to investigate changes in food intake, eating behaviors, and diet quality during lockdown as compared with before the lockdown. A literature search was performed using 3 electronic databases from inception until 13 June 2021. Observational studies evaluating changes in general populations during the COVID-19 pandemic lockdown were eligible. Of 1963 studies retrieved from the search strategy, 95 met inclusion criteria (85 in adults, 10 in children/adolescents), and the majority were of high quality (72.6%). Most of the studies were web-based surveys using convenience sampling, mainly focused on variations in the consumption of foods and eating behaviors during lockdown, whereas only 15 studies analyzed diet quality through dietary indices. On the basis of the definition of a healthful diet as reflected by a traditional Mediterranean diet, an increase in recommended foods such as fruit and vegetables, legumes, cereals, and olive oil was observed, although a sharp decrease in fish intake and an increase in dairy products were documented. Accordingly, a reduction in foods that should be eaten less frequently was reported-namely, red and processed meat. However, a higher consumption of unhealthy foods (e.g., snacks and sweets) was also observed. Results indicated improved diet quality in Europe, especially among Mediterranean countries, with the exception of France, while a switch to poor nutrient patterns was observed in Colombia and Saudi Arabia. Analyses of eating behaviors suggest an increase in food intake, number of daily meals, and snacking. In conclusion, changes in intake of major food groups, apart from fish intake, were in line with the definition of a traditional Mediterranean diet, indicating a consistent moderate improvement in dietary habits worldwide. This review protocol was registered at https://www.crd.york.ac.uk/prospero/ as CRD42020225292.

The inflammatory potential of the diet as a link between food processing and low-grade inflammation: An analysis on 21,315 participants to the Moli-sani study.

BACKGROUND & AIMS: Food processing may adversely affect human health through a variety of mechanisms, including the development of a chronic pro-inflammatory state. In this study we aimed to test the hypothesis that an increasing degree of food processing is directly associated with low-grade inflammation, and evaluate to what extent this association is mediated by the inflammatory potential of highly processed foods. METHODS: Cross-sectional analysis on 21,315 subjects (mean age 55 ± 3 y) from the Moli-sani Study with complete dietary data collected by a validated 188-item food frequency questionnaire. The NOVA classification was used to categorize foods on the basis of industrial processing as: 1) unprocessed/minimally processed foods; 2) processed culinary ingredients; 3) processed foods; 4) ultra-processed foods (UPF). The inflammatory potential of the diet was evaluated through the Energy-adjusted Dietary Inflammatory Index (E-DII™). Low-grade inflammation was assessed by a composite INFLA-score including C-reactive protein, leukocyte and platelet counts and the granulocyte to lymphocyte ratio. RESULTS: In multivariable-adjusted linear regression models, the INFLA-score was positively associated with E-DII (ß = 0.15; 0.10, 0.19), processed foods (ß = 0.04; 0.01, 0.08) and UPF (ß = 0.13; 0.07, 0.19), but inversely associated with minimally processed foods (ß = -0.09; -0.13, -0.06). The E-DII score was inversely associated with minimally processed food (ß = -0.40; 95%CI -0.41, -0.39 for 5% increment in the weight ratio) but directly with either processed culinary ingredients (ß = 0.18; 0.15, 0.21 for 1% increment), processed food (ß = 0.28; 0.27, 0.29 for 5% increment) or UPF (ß = 0.34; 0.32, 0.36 for 5% increment). The inclusion of the E-DII into the multivariable model explained 88.5% of the association of processed food with the INFLA-score (p < 0.0001) and mitigated by 32.6% (p < 0.0001) the association with UPF. CONCLUSIONS: The association of UPF with low-grade inflammation is only partially explained by the high pro-inflammatory potential of these foods. Further studies are warranted to test whether the observed adverse relationship of UPF with low-grade inflammation could be triggered by mechanisms that are not directly related to the pro-inflammatory potential of highly processed food products.