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Plant-based dietary patterns, including vegetarian and vegan dietary patterns, may help to manage type 2 diabetes (T2DM) by contributing to maintenance of a healthy body weight, improved glycemic control, and reduced risk of diabetes complications. Several diabetes clinical practice guidelines support the use of vegetarian dietary patterns, but there has not been a recently updated systematic review (SR) of evidence from randomized controlled trials (RCTs) to examine efficacy. The primary objective of this SR was to examine the effect of vegetarian dietary patterns compared with nonvegetarian dietary patterns in adults with T2DM. MEDLINE, CINAHL, Cochrane CENTRAL Database of Controlled Trials, Food Science Source, and SportsDiscus databases were searched for RCTs published from 1998 to May 2023. Two independent reviewers extracted data and assessed risk of bias using the Cochrane RoB 2 tool. Data were pooled using a DerSimonian-Laird random-effects model and expressed as mean differences (MDs) with 95% confidence intervals (CIs). Heterogeneity was assessed using the I2 statistic, and certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Full texts of 66 articles were reviewed, and 7 RCTs (n = 770 participants) were included in this SR. Vegetarian dietary patterns likely reduce hemoglobin A1c [MD (95% CI): -0.40% (-0.59, -0.21)] and body mass index [MD (95% CI): -0.96 kg/m2 (-1.58, -0.34)] (moderate certainty evidence); may allow for reduced diabetes medication (in 2 of 3 included studies) (low certainty); and may improve metabolic clearance of glucose (insulin sensitivity) [MD (95% CI): 10% (1.86, 18.14)] (very low certainty), compared with nonvegetarian dietary patterns. There were no effects of vegetarian dietary patterns on fasting blood glucose, fasting insulin, or low-density lipoprotein cholesterol concentrations. These findings support the inclusion of vegetarian or vegan dietary patterns as options in nutrition care plans for adults with T2DM. PROSPERO REGISTRATION: CRD42023396453.
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Diabetes Mellitus Tipo 2 , Dieta Vegana , Dieta Vegetariana , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/terapia , Adulto , Masculino , Glicemia/metabolismo , Feminino , Pessoa de Meia-Idade , Hemoglobinas Glicadas/análise , Padrões DietéticosRESUMO
Background: Diet significantly influences the risk of developing cardiovascular disease (CVD), the leading cause of death in the United States. As vegetarian dietary patterns are increasingly being included within clinical practice guidelines, there is a need to review the most recent evidence regarding if and how these dietary patterns mitigate CVD risk. Objective: This umbrella review of systematic reviews compared the relationships between vegetarian, vegan and non-vegetarian dietary patterns and CVD health outcomes and risk factors among presumably healthy adults (≥18 years) in the general population. Methods: MEDLINE, CINAHL, Cochrane Databases of Systematic Reviews, Food Science Source and SportsDiscus databases were searched for systematic reviews (SRs) published from 2018 until March 2024. Eligible SRs and meta-analyses examined relationships between vegetarian or vegan diets and CVD risk factors and disease outcomes compared to non-vegetarian diets. SRs were screened in duplicate, and SR quality was assessed with AMSTAR2. The overall certainty of evidence (COE) was evaluated using the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) method. Results: There were 758 articles identified in the databases' search and 21 SRs met inclusion criteria. SRs targeting the general population had primarily observational evidence. Vegetarian, including vegan, dietary patterns were associated with reduced risk for CVD incidence [Relative Risk: 0.85 (0.79, 0.92)] and CVD mortality [Hazard Ratio: 0.92 (0.85, 0.99)] compared to non-vegetarian diets. Vegan dietary patterns were associated with reductions in CVD risk factors including blood pressure [systolic mean difference (95 % CI): -2.56 mmHg (-4.66, -0.445)], low-density lipoprotein cholesterol [-0.49 mmol/l (-0.62, -0.36)], and body mass index [-1.72 kg/m2 (-2.30, -1.16)] compared to non-vegetarian dietary patterns, as well as c-reactive protein concentrations in a novel meta-analysis [-0.55 mg/l (-1.07, -0.03)]. Conclusion: Practitioners can consider recommending vegetarian dietary patterns to reduce cardiometabolic risk factors and risk of CVD incidence and mortality.
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BACKGROUND: Hypertension is an important risk factor for cardiovascular disease (CVD). Interventions with dietitians can help modify dietary intake and reduce hypertension risk. OBJECTIVES: We aimed to examine the following research question: In adults with prehypertension or hypertension, what is the effect of medical nutrition therapy (MNT) provided by a dietitian on blood pressure (BP), CVD risk and events, and anthropometrics compared with standard care or no intervention? METHODS: MEDLINE, CINAHL, and Cochrane Central databases were searched for randomized controlled trials (RCTs) published in peer-reviewed journals from 1985-2022. Risk of bias was assessed using version 2 of the Cochrane tool for RCTs. Meta-analyses were conducted using the DerSimonian-Laird random-effects model. Certainty of evidence (COE) was assessed for each outcome using the Grading of Recommendations, Assessment and Evaluation method. RESULTS: Forty articles representing 31 RCTs were included and analyzed. MNT provided by a dietitian may reduce systolic [mean difference (MD): -3.63 mmHg; 95% confidence interval (CI): -4.35, -2.91 mmHg] and diastolic (MD: -2.02 mmHg; 95% CI: -2.56, -1.49 mmHg) BP (P < 0.001) and body weight (MD: -1.84 kg; 95% CI: -2.72, -0.96 kg; P < 0.001) and improve antihypertensive medication usage, relative risk of stroke (MD: 0.34; 95% CI: 0.14, 0.81; P = 0.02), and CVD risk score [standardized mean difference (SMD): -0.20; 95% CI: -0.30, -0.09; P < 0.001] compared with control participants, and COE was moderate. Additionally, MNT may reduce arterial stiffness (SMD: -0.45; 95% CI: -0.71, -0.19; P = 0.008) and waist circumference (SMD: -1.18 cm; 95% CI: -2.00, -0.36; P = 0.04), and COE was low. There was no significant difference in risk of myocardial infarction between groups. Dietitian interventions reduced BP and related cardiovascular outcomes for adults with prehypertension or hypertension. CONCLUSIONS: Dietitians play a critical role in improving cardiometabolic risk factors for adults with elevated BP; thus, improved payment for and access to MNT services has the potential to significantly impact public health. This review was registered at PROSPERO as CRD42022351693.
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Hipertensão , Terapia Nutricional , Nutricionistas , Pré-Hipertensão , Humanos , Hipertensão/dietoterapia , Pré-Hipertensão/dietoterapia , Terapia Nutricional/métodos , Adulto , Pressão SanguíneaRESUMO
Characterization of the nutrients in human milk is important to understand the dietary and developmental requirements of infants. The objective of this review was to summarize the state-of-the-science on the nutrient composition of human milk in the United States and Canada published from 2017 to 2022. Four databases were searched for randomized controlled studies and others given the scoping nature of this review. We limited type to mature milk collected 21 d postpartum and beyond from lactating individuals in the United States and Canada who gave birth at 37-wk gestation or later (full-term). Outcomes of interest included traditional macro- and micronutrients, including human milk oligosaccharides (HMOs), and milk volume. The publication date range was selected as January 1, 2017, to the day the literature search was performed. A total of 32 articles were included in the scoping review from primarily longitudinal cohort or cross-sectional designs. The most prevalent sample collection method was full-breast expression (n = 20) with most studies (n = 26) collecting samples from a single timepoint. Carbohydrates (HMOs [n = 12], glucose [n = 8], and lactose [n = 6]) and protein (n = 5) were the most frequently assessed nutrients in this body of work, with consensus among studies that glucose is present in limited concentrations compared to lactose (24-64 mg/dL compared with 6-7 g/dL) and that HMOs are influenced by temporality and secretor status. Included studies displayed an overall level of heterogeneity and sparsity paralleling previous reports and nutrient data in the USDA FoodData Central system. Much of the data extracted from retained articles generally provided analysis of a specific nutrient or group of nutrients. Moreover, many studies did not use the preferred analytical methods as outlined by the Human Milk Composition Initiative to increase measurement confidence. Up-to-date nutrient composition data of human milk is still greatly needed as it is paramount for the management of infant feeding, assessment of infant and maternal nutritional and health needs, and as a reference for infant formula development.
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Lactação , Leite Humano , Lactente , Feminino , Humanos , Estados Unidos , Leite Humano/química , Estudos Transversais , Lactose , Oligossacarídeos , Micronutrientes/análise , Glucose , Fenômenos Fisiológicos da Nutrição do LactenteRESUMO
BACKGROUND: A total of 374 million adults worldwide are living with prediabetes, 70% of whom will develop type 2 diabetes mellitus (T2DM) in their lifetime. Medical nutrition therapy (MNT) provided by a dietitian, such as that found in lifestyle interventions, has the potential to improve glycemic control and prevent progression to T2DM. OBJECTIVES: The objective of this systematic review was to examine the effectiveness of MNT provided by a dietitian, compared with standard care, on glycemic, cardiometabolic, and anthropometric outcomes in adults with prediabetes. METHODS: Searches were conducted for randomized controlled trials (RCTs) published between 1995 and 2022 using electronic databases MEDLINE, CINHAL, and Cochrane Central. The risk of bias was assessed using version 2 of the Cochrane risk-of-bias tool for RCTs. Meta-analyses were conducted using a random-effects model. The certainty of evidence was assessed for each outcome using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method, and a summary of findings table was created using the GRADEpro Guideline Development Tool. RESULTS: Thirteen RCTs were included in the analysis, showcasing a variety of MNT interventions delivered by dietitians. Intervention durations ranged from 3 to 24 mo. Compared with standard care, MNT improved hemoglobin A1c (HbA1c) (mean difference [95% confidence interval]: -0.30% [-0.49, -0.12]) and fasting blood glucose (FBG) (-4.97 mg/dL [-6.24, -3.71]). Statistically significant improvements were found in anthropometrics (weight, body mass index, and waist circumference), cholesterol (total, high-, and low-density lipoproteins), and blood pressure (systolic and diastolic). No significant effect was found on T2DM or triglycerides. The certainty of evidence was moderate for FBG and low for HbA1c and incidence of T2DM. CONCLUSIONS: In adults with prediabetes, MNT was effective in improving glycemic outcomes, anthropometrics, blood pressure, and most lipid levels. However, most studies had a risk of bias because of the randomization process or deviations from intended interventions. MNT plays a key role in improving cardiometabolic risk factors in adults with prediabetes. TRIAL REGISTRATION NUMBER: This study was registered with the registration ID #351421, available from https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=351421.
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Diabetes Mellitus Tipo 2 , Terapia Nutricional , Nutricionistas , Estado Pré-Diabético , Humanos , Adulto , Estado Pré-Diabético/terapia , Hemoglobinas Glicadas , Terapia Nutricional/métodosRESUMO
Oral and vascular diseases are seemingly disparate conditions, yet individuals with poor oral health are at increased risk for cardiovascular events. Spice-derived bioactive polyphenols with antioxidant functionality may attenuate mechanisms linking the diseases, namely oxidative stress and inflammation. Acknowledging that novel approaches to increase antioxidant intake are warranted, the purpose of this study was to evaluate the influence of two functional sugar-free gums infused with spices on antioxidant capacity and phenolic content of saliva using the oxygen radical absorbance capacity and Folin-Ciocalteu assays, respectively. Unstimulated followed by stimulated saliva was collected according to a validated method across a prescribed five minute chewing period. Both gums significantly increased hydrophilic, lipophilic, and total antioxidant capacity of saliva (p < 0.05) yet to varying extents. Phenolic content of saliva was significantly higher (p < 0.001) post-chew for both gums. Results suggest spices infused into sugar-free chewing gum bolster the antioxidant capacity of saliva, thereby promoting oral health. Research evaluating the sublingual absorption of spice-derived antioxidants in functional gums and their influence on systemic oxidative stress is warranted.
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Goma de Mascar , Saliva , Humanos , Antioxidantes , Concentração de Íons de Hidrogênio , FenóisRESUMO
Guideline recommendation for a plant bioactive such as flavan-3-ols is a departure from previous recommendations because it is not based on deficiencies but rather improvement in health outcomes. Nevertheless, there is a rapidly growing body of clinical data reflecting benefits of flavan-3-ol intake that outweigh potential harms. Thus, the objective of the Expert Panel was to develop an intake recommendation for flavan-3-ols and cardiometabolic outcomes to inform multiple stakeholders including clinicians, policymakers, public health entities, and consumers. Guideline development followed the process set forth by the Academy of Nutrition and Dietetics, which includes use of the Evidence to Decision Framework. Studies informing this guideline (157 randomized controlled trials and 15 cohort studies) were previously reviewed in a recently published systematic review and meta-analysis. Quality and strength-of-evidence along with risk-of-bias in reporting was reviewed. In drafting the guideline, data assessments and opinions by authoritative scientific bodies providing guidance on the safety of flavan-3-ols were considered. Moderate evidence supporting cardiometabolic protection resulting from flavan-3-ol intake in the range of 400-600 mg/d was supported in the literature. Further, increasing consumption of dietary flavan-3-ols can help improve blood pressure, cholesterol concentrations, and blood sugar. Strength of evidence was strongest for some biomarkers (i.e., systolic blood pressure, total cholesterol, HDL cholesterol, and insulin/glucose dynamics). It should be noted that this is a food-based guideline and not a recommendation for flavan-3-ol supplements. This guideline was based on beneficial effects observed across a range of disease biomarkers and endpoints. Although a comprehensive assessment of available data has been reviewed, evidence gaps identified herein can inform scientists in guiding future randomized clinical trials.
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Doenças Cardiovasculares , Flavonoides , Humanos , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Dieta , Suplementos Nutricionais , Glicemia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/tratamento farmacológico , BiomarcadoresRESUMO
BACKGROUND: Excess adiposity is characterized by alterations in adipokine secretion such that circulating leptin concentrations are increased with reductions in adiponectin. An emerging biomarker for the assessment of this adipose tissue (AT) dysfunction is the adiponectin:leptin (AL) ratio. A low AL ratio may be suggestive of dysfunctional AT and, consequently, a heightened cardiometabolic disease risk. This ancillary study investigated the relationship between the AL ratio and cardiometabolic health among community-dwelling older adults with obesity, as well as the effects of a 12-month exercise and diet intervention on changes in the AL ratio. METHODS: Participants (n = 163, 70.2 ± 4.7 years, 38.0% male) were randomized to the exercise only group, exercise + nutrient-dense weight maintenance group (exercise + weight maintenance), or exercise + nutrient-dense caloric restriction of 500 kcal/d group (exercise + intentional weight loss) (clinicaltrials.gov #NCT00955903). Total and regional adiposity as determined by magnetic resonance imaging (MRI) and dual-energy X-ray absorptiometry (DXA), anthropometrics, and cardiometabolic biomarkers were assessed at baseline and 12 months. RESULTS: The AL ratio was significantly (p < 0.05) inversely correlated with body mass index, waist circumference, measures of adiposity, and insulin among all participants at baseline. Among females only, significant positive and inverse correlations were also observed between this ratio and high-density lipoprotein cholesterol and the inflammatory biomarkers high sensitivity C-reactive protein and interleukin-6, respectively. While controlling for biological sex, a significant time by intervention group interaction effect (p < 0.05) was observed such that the AL ratio significantly increased from baseline to study completion among participants in the exercise + weight maintenance group and exercise + intentional weight loss group. Post hoc analysis revealed that the exercise + intentional weight loss group exhibited a significantly greater AL ratio at study completion compared to other groups (p < 0.05 all). CONCLUSIONS: Results are in support of the AL ratio as a measure of AT dysfunction among older adults. Furthermore, results suggest that a 12-month exercise and diet intervention with intentional weight loss assists in improving the AL ratio in this population.
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Doenças Cardiovasculares , Leptina , Adiponectina/metabolismo , Idoso , Biomarcadores , Dieta Redutora , Feminino , Humanos , Leptina/metabolismo , Masculino , Obesidade/metabolismo , Redução de PesoRESUMO
BACKGROUND/OBJECTIVES/INTRODUCTION: It is imperative to accurately estimate whole body fat percentage (%fat) to understand the deleterious nature of excess adiposity on cardiometabolic disease risk. Cost and accessibility often preclude the use of advanced imaging methods like dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI). Relative fat mass (RFM) is an emerging estimator of whole body %fat based on waist circumference, height, and biological sex. The purpose of this ancillary study was to examine the relationship between RFM and gold-standard measures of adiposity among community-dwelling older adults with obesity and to evaluate if changes in RFM reflect changes in %fat following a 12-month lifestyle intervention (clinicaltrials.gov #NCT00955903). PATIENTS/MATERIALS AND METHODS: Participants (N = 163, 37.4% male, 70.3 ± 4.7 years) were randomized to the exercise only group, exercise + nutrient-dense weight maintenance group, or exercise + nutrient-dense energy restriction of 500 kcal/d group. Total and regional adiposity assessed by DXA and MRI, as well as anthropometrics, were evaluated at baseline and 12 months. RESULTS: RFM was significantly positively correlated with DXA whole body %fat and DXA trunk %fat at baseline. Equivalence testing revealed that RFM was considered equivalent to DXA whole body %fat for females only. Additionally, from baseline to 12 months, a significant reduction in RFM was observed among female participants in the exercise + energy restriction group only. Changes in RFM were significantly correlated with changes in DXA whole body %fat, DXA trunk fat, and total abdominal fat tissue determined by MRI. CONCLUSION: Results support the use of RFM as an estimate of whole body %fat where advanced imaging techniques are not feasible. Furthermore, results suggest that this index is sensitive to changes in fat mass over 12 months in female older adults with obesity. KEY MESSAGESRelative fat mass (RFM), an emerging estimator of whole body %fat based on waist circumference, height, and biological sex, was intentionally developed to be a simple estimate of adiposity that overcomes limitations of measures like body mass index.In the current study, results from correlations and agreement analyses support the use of RFM to estimate whole-body fat percentage in a community-dwelling older adult population with obesity when advanced methods, namely dual-energy X-ray absorptiometry, are not feasible.Significant reductions in RFM were also observed over a 12-month period that was significantly correlated with changes in whole body fat percentage; thus, supporting the sensitivity of RFM to lifestyle changes.
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Adiposidade , Obesidade , Absorciometria de Fóton/métodos , Idoso , Índice de Massa Corporal , Dieta , Feminino , Humanos , Masculino , Obesidade/diagnóstico por imagem , Obesidade/terapiaRESUMO
Dietary patterns high in fat influence local and systemic oxidative stress through adipose tissue (AT) accrual and increased reactive oxygen species generation. Lycopene, a carotenoid with antioxidant functionality, may mitigate excess oxidative stress, yet the lipophilic nature of this compound may limit its functionality if sequestered by AT. Thus, it is critical to elucidate whether lycopene's efficacy is limited based on adiposity. The purpose of this study was to investigate the influence of lycopene-supplemented normal- and high-fat diets on systemic and AT redox status. Male Sprague-Dawley rats (n = 18) were fed a 30% normal-fat (NFD) or 60% high-fat (HFD) purified diet supplemented with 100 mg of lycopene/day. Body weight and visceral AT mass, as well as serum and AT lycopene, lipid peroxides, and antioxidant capacity (AC), were assessed after 3, 7, and 10 weeks of supplementation. At week 10, AT mass was significantly higher (P = .028) in the HFD group, yet there were no significant differences in serum or AT lycopene concentrations or lipid peroxides between groups. Additionally, AT in the HFD group exhibited significantly greater lipophilic AC (27.6% higher, P = .031). Results suggest that excess adiposity did not negatively influence circulating lycopene, nor did it limit its antioxidant functionality.
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Tecido Adiposo , Dieta Hiperlipídica , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Licopeno , Masculino , Oxirredução , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Vitamin A (VA) has been demonstrated to be a regulator of adipose tissue (AT) development in adult obese models. However, little is known about the effect of VA on obesity-associated developmental and metabolic conditions in early life. OBJECTIVES: We aimed to assess the effects of dietary VA supplementation during suckling and postweaning periods on the adiposity and metabolic health of neonatal and weanling rats from mothers consuming a high-fat diet (HFD). METHODS: Pregnant Sprague-Dawley rats were fed a normal-fat diet (NFD; 25% fat; n = 2) or an HFD (50% fat; n = 2), both with 2.6 mg VA/kg. Upon delivery, half of the rat mothers were switched to diets with supplemented VA at 129 mg/kg, whereas the other half remained at 2.6 mg VA/kg. Four groups of rat pups were designated as NFD, NFD + VA, HFD, and HFD + VA, respectively. At postnatal day (P)14, P25, and P35, pups (n = 4 or 3/group) were killed. Body weight (BW), visceral white AT (WAT) mass, brown AT (BAT) mass, uncoupling protein 1 mRNA expression in BAT, serum glucose, lipids, adipokines, and inflammatory biomarkers, as well as serum and AT redox status were assessed. RESULTS: Rat pups in the HFD group exhibited significantly higher BW, WAT mass, and serum glucose and leptin but reduced BAT mass compared with the NFD group. Without affecting the dietary intake, supplementing the HFD with VA significantly reduced the BW and WAT mass of pups but increased the BAT mass, significantly lowered the systemic and WAT oxidative stress, and modulated serum adipokines and lipids to some extent. CONCLUSIONS: VA supplementation during suckling and postweaning periods attenuated metabolic perturbations caused by excessive fat intake. Supplementing maternal or infant obesogenic diets with VA or establishing a higher RDA of VA for specific populations should be studied further for managing overweight/obesity in early life.
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The enterosalivary nitrate-nitrite-nitric oxide (NO) pathway results in systemic generation of NO from dietary inorganic nitrate to promote vasodilation and blood pressure regulation. Commensal bacteria in the oral cavity with nitrate-reducing properties underpin the efficiency of this pathway, as they facilitate the reduction of nitrate to nitrite-a critical activation step preceding NO formation. However, common antibacterial mouth rinses rid the oral cavity of these bacteria and, thus, may have local and systemic consequences. The purpose of this systematic review was to investigate the relationship between mouth rinse use and salivary or plasma nitrates/nitrites, as well as blood pressure. A systematic review was conducted utilizing PubMed and EBSCOhost databases to identify publications evaluating mouth rinse use on salivary and/or plasma nitrate/nitrite concentrations and blood pressure. In addition to inclusion of the aforementioned outcome measures, studies must have been published in scholarly, peer-reviewed journals. Data extraction and quality assessment were independently conducted by the Authors with tools created by the Academy of Nutrition and Dietetics. Methods were registered with the International Prospective Register of Systematic Reviews (CRD42019125081). Eight studies were identified for critical appraisal, including 5 human crossover studies and 3 animal studies with controls, published between 2009 and 2016. All human studies and two of the three animal studies revealed deleterious effects of an antibacterial mouth rinse on at least one of the outcome measures. For example, in human studies comparing antibacterial mouth rinses to control, 5 of 5 studies and 3 of 5 studies reported reduced salivary and plasma nitrite concentrations, respectively, and 4 of 5 studies observed increased blood pressure. Likewise, 2 of 3 animal studies reported reduced plasma nitrite compared to control as well as increased blood pressure. Differential effects on outcome measures were noted in mouth rinses of varying strengths and compositions. Results suggest that the utilization of an antibacterial mouth rinse negatively alters concentrations of salivary and plasma nitrate/nitrite with a concomitant rise in blood pressure. Acknowledging the rising prevalence of hypertension, future research is warranted to develop functional mouth rinses that support oral and cardiovascular health, as well as nutrition interventions to optimize the enterosalivary pathway for blood pressure regulation.
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Antissépticos Bucais , Saliva , Animais , Pressão Sanguínea , Humanos , Boca , Nitratos , Óxido Nítrico , NitritosRESUMO
Cardiometabolic risk factors increase the likelihood of cardiovascular disease development by 2-fold. Lycopene, a potent lipophilic antioxidant, may be able to mediate oxidative stress, a mechanism underpinning metabolic syndrome (MetS) and its risk factors. This is, to our knowledge, the first systematic review of the literature with the purpose of investigating the relation between circulating lycopene or dietary intake of lycopene and MetS as well as its risk factors. The review was conducted using PubMed and EBSCOhost databases with the search terms "lycopene" and "metabolic syndrome." Inclusion criteria included human studies published in English in a scholarly, peer-reviewed journal and evaluation of lycopene in relation to ≥3 of the 5 MetS risk factors as defined by the National Cholesterol Education Program's Adult Treatment Panel III (ATP III) report. The process identified 11 studies, including 8 cross-sectional and 3 intervention studies. Cross-sectional studies were grouped into 3 categories, with several studies falling into >1 category, based on results reporting associations of lycopene with the prevalence and outcomes of MetS (5 studies), presence of ATP III risk factors (4 studies), and variables mediating lycopene's influence on MetS risk (3 studies). All studies in each category reported significant protective associations. Of the 3 intervention studies, all reported significant protective effects from a lycopene-rich beverage, despite varying doses and durations of intake. Although a protective relation between lycopene and MetS was generally supported, different MetS components appeared to be influenced by lycopene rather than demonstrating consistent improvement in a single component. Thus, additional research is needed to elucidate the mechanistic effects of lycopene on MetS, as well as to determine evidence-based recommendations concerning dose-durational effects of lycopene and MetS risk reduction. In conclusion, the evidence of lycopene's benefit exists such that lycopene status or lycopene consumption may be associated with favorable alterations to the components of MetS.