ABSTRACT
PURPOSE OF REVIEW: This review uses the hierarchy of evidence as a framework to critically evaluate the effect of long chain n -3 polyunsaturated fatty acid (LC n -3 PUFA) ingestion alone, or as an adjunctive intervention to resistance training, on muscle health-related outcomes in healthy and clinical older adult populations. RECENT FINDINGS: Systematic reviews and meta-analyses of randomized controlled trials consistently report small, but clinically-relevant, effects of LC n -3 PUFA ingestion on strength outcomes, whereas mixed findings have been reported regarding changes in muscle mass and physical function. Cohort studies indicate an association between higher dietary LC n -3 PUFA intake and reduced likelihood of a sarcopenia diagnosis. Acute metabolic studies provide limited evidence for an effect of LC n -3 PUFA ingestion alone, or in combination with resistance training, on free-living integrated rates of MPS, static markers of muscle protein breakdown, or satellite cell activation in healthy older adults. SUMMARY: Recent data supports the efficacy of LCn-3 PUFA ingestion to facilitate small, but clinically relevant, improvements in muscle strength in healthy and clinical older adult populations. The mechanism(s) that underpin the action of LC n -3 PUFA in promoting strength outcomes remain unknown, but likely relate to neuromuscular function.
Subject(s)
Fatty Acids, Omega-3 , Sarcopenia , Humans , Aged , Fatty Acids, Omega-3/metabolism , Dietary Supplements , Sarcopenia/metabolism , Muscle Strength , Fatty Acids/metabolism , Muscle, Skeletal/metabolismABSTRACT
The main objective of the current study was to perform a systematic literature review with the purpose of exploring the impact of long-chain n-3 polyunsaturated fatty acid (LCn-3 PUFA) relative to control oil supplementation on muscle strength, with secondary outcomes of muscle mass and physical function in older individuals under conditions of habitual physical activity/exercise. The review protocol was registered with PROSPERO (CRD42021267011) and followed the guidelines outlined in the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. The search for relevant studies was performed utilizing databases such as PubMed, EMBASE, CINAHL, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) up to June 2023. Randomized controlled trials (RCTs) in older adults comparing the effects of LCn-3 PUFA with a control oil supplement on muscle strength were included. Five studies involving a total of 488 participants (348 females and 140 males) were identified that met the specified inclusion criteria and were included. Upon analyzing the collective data from these studies, it was observed that supplementation with LCn-3 PUFA did not have a significant impact on grip strength (standardized mean difference (SMD) 0.61, 95% confidence interval [-0.05, 1.27]; p = 0.07) in comparison to the control group. However, there was a considerable level of heterogeneity among the studies (I2 = 90%; p < 0.001). As secondary outcomes were only measured in a few studies, with significant heterogeneity in methods, meta-analyses of muscle mass and functional abilities were not performed. Papers with measures of knee extensor muscle mass as an outcome (n = 3) found increases with LCn-3 PUFA supplementation, but studies measuring whole body lean/muscle mass (n = 2) and functional abilities (n = 4) reported mixed results. With a limited number of studies, our data indicate that LCn-3 PUFA supplementation has no effect on muscle strength or functional abilities in older adults but may increase muscle mass, although, with only a few studies and considerable heterogeneity, further work is needed to confirm these findings.
Subject(s)
Fatty Acids, Omega-3 , Muscle Strength , Female , Male , Humans , Aged , Hand Strength , Dietary Supplements , Fatty Acids , Muscle, Skeletal , Fatty Acids, Omega-3/pharmacologyABSTRACT
PURPOSE: The perceived benefits and risks associated with seed oil intake remain controversial, with a limited number of studies investigating the impact of intake on a range of compounds used as cardiometabolic markers. This study aimed to explore the proteomic and cardiometabolic effects of commonly consumed seed oils in the UK, with different fatty acid profiles. METHODS: In a parallel randomised control design, healthy adults (n = 84), aged 25-72 with overweight or obesity were randomised to one of three groups: control (habitual diet, CON); 20 mL rapeseed oil per day (RO), or 20 mL sunflower oil per day (SO). Blood, spot urine and anthropometric measures were obtained at 0, 6 and 12 weeks. Proteomic biomarkers analysis was conducted for coronary arterial disease (CAD) and chronic kidney disease (CKD) using capillary electrophoresis coupled to mass spectrometry (CE-MS). Blood lipids, fasting blood glucose, glycative/oxidative stress and inflammatory markers were also analysed. RESULTS: No differences in change between time points were observed between groups for CAD or CKD peptide fingerprint scores. No change was detected within groups for CAD or CKD scores. No detectable differences were observed between groups at week 6 or 12 for the secondary outcomes, except median 8-isoprostane, ~ 50% higher in the SO group after 12-weeks compared to RO and CON groups (p = 0.03). CONCLUSION: The replacement of habitual fat with either RO or SO for 12 weeks does not lead to an improvement or worsening in cardiovascular health markers in people with overweight or obesity. TRIAL REGISTRATION: Trial registration clinicaltrials.gov NCT04867629, retrospectively registered 30/04/2021.
Subject(s)
Coronary Artery Disease , Helianthus , Renal Insufficiency, Chronic , Adult , Biomarkers , Humans , Obesity , Overweight , Plant Oils/pharmacology , Proteomics , Rapeseed Oil , Sunflower OilABSTRACT
Chronic kidney disease (CKD) manifests with systemic inflammation, oxidative stress, and gut dysbiosis, resulting in metabolic disorders and elevated rates of cardiovascular disease-associated death. These all correlate with a high economic cost to healthcare systems. Growing evidence indicates that diet is an indispensable ally in the prevention and management of CKD and its complications. In this context, the root vegetable beetroot (Beta vulgaris rubra) deserves special attention because it is a source of several bioactive compounds, such as nitrate, betaine, and betalain, and has shown beneficial effects in CKD, including reduction of blood pressure, anti-inflammatory effects, and antioxidant actions by scavenging radical oxidative species, as observed in preclinical studies. Beetroot consumption as a possible therapeutic strategy to improve the clinical treatment of patients with CKD and future directions for clinical studies are addressed in this narrative review.
Subject(s)
Beta vulgaris , Renal Insufficiency, Chronic , Antioxidants/therapeutic use , Dysbiosis , Humans , Renal Insufficiency, Chronic/drug therapy , VegetablesABSTRACT
To explore the factors (including knowledge and attitude) influencing the decision to follow a low-carbohydrate diet (LCD) or not in a sample of the UK population. An online questionnaire was distributed electronically to adults who had either followed LCD or not (February-December 2019). Demographics and self-reported "LCD-status" (current, past and non-follower) were collected. Multivariable linear regression was used with carbohydrate knowledge, dietary guideline agreement and theory of planned behaviour (TPB) constructs (all as predictors) to explain the intention to follow a LCD (outcome). Respondents (n = 723, 71% women, median age 34; 85% white-ethnicity) were either following (n = 170, 24%) or had tried a LCD in the preceding 3 months (n = 184, 25%). Current followers had lower carbohydrate knowledge scores (1-2 point difference, scale - 11 to 11) than past and non-followers. A majority of current LCD followers disagreed with the EatWell guide recommendations "Base meals on potatoes, bread, rice and pasta, or other starchy carbohydrates. Choose whole grains where possible" (84%) and "Choose unsaturated oils and spreads and eat in small amounts such as vegetable, rapeseed, olive and sunflower oils" (68%) compared to past (37%, 10%, respectively) and non-followers (16%, 8%, respectively). Weight-loss ranked first as a motivation, and the internet was the most influencial source of information about LCDs. Among LCD-followers, 71% reported ≥ 5% weight loss, and over 80% did not inform their doctor, nurse, or dietitian about following a diet. Approximately half of LCD followers incorporated supplements to their diets (10% used multivitamin/mineral supplements), despite the restrictive nature of the diet. TPB constructs, carbohydrate knowledge, and guideline agreement explained 60% of the variance for the intention to follow a LCD. Attitude (std-ß = 0.60), perceived behavioural control (std-ß = 0.24) and subjective norm (std-ß = 0.14) were positively associated with the intention to follow a LCD, while higher knowledge of carbohydrate, and agreeing with national dietary guidelines were both inversely associated (std-ß = - 0.09 and - 0.13). The strongest primary reason behind UK adults' following a LCD is to lose weight, facilitated by attitude, perceived behavioural control and subjective norm. Higher knowledge about carbohydrate and agreement with dietary guidelines are found among people who do not follow LCDs.
Subject(s)
Diet, Carbohydrate-Restricted/psychology , Health Knowledge, Attitudes, Practice , Nutrition Surveys/statistics & numerical data , Adult , Culture , Female , Humans , Male , Middle Aged , Motivation , Nutrition Policy , Social Class , United KingdomABSTRACT
This study investigated the efficacy of participation in culture-specific dancing to meet current physical activity recommendations and increase cardio-respiratory fitness in postmenopausal women. Sedentary postmenopausal women (n = 24), aged 63 ± 8 years and with BMI of 28 ± 3 kg/m2 completed a 4-week Scottish dancing study. The dancing sessions of approximately 75 min were performed twice a week and each session was based on five Scottish dances performed in 3 sets. Heart rate (HR) measurements were obtained during all dances to evaluate whether the intervention achieves the criteria of moderate to vigorous aerobic exercise intensity. Body composition, waist circumference, and HR during Chester Step test were measured before and after dancing intervention. HR achieved during individual dances ranged from 64 ± 5% to 80 ± 5% of HRmax and the mean HR of the five dances corresponded to 72 ± 7% of HRmax. Post-intervention mean HR was lower throughout Level 2 (Pre, 112 ± 13 bpm; Post, 106 ± 13 bpm; p = 0.005) and Level 3 (Pre, 122 ± 14 bpm; Post, 115 ± 14 bpm; p = 0.006) of the Chester test compared with baseline values. The intervention had no impact on body weight or body fat but reduced waist circumference (Pre, 94 ± 8 cm; Post, 91 ± 9 cm; p = 0.006). Thus, traditional Scottish dancing should be advocated to sedentary postmenopausal women, emphasising its potential in meeting current physical activity recommendations in relation of weekly duration and exercise intensity and improving cardiorespiratory fitness.
Subject(s)
Dance Therapy/methods , Dancing , Exercise , Heart Rate/physiology , Postmenopause/psychology , Aged , Exercise Test , Female , Humans , Middle Aged , Physical Fitness , Scotland , Waist CircumferenceABSTRACT
Low-carbohydrate diets (LCD) have been promoted for weight control and type 2 diabetes (T2D) management, based on an emerging body of evidence, including meta-analyses with an indication of publication bias. Proposed definitions vary between 50 and 130 g/d, or <10 and <40 % of energy from carbohydrate, with no consensus on LCD compositional criteria. LCD are usually followed with limited consideration for other macronutrients in the overall diet composition, introducing variance in the constituent foods and in metabolic responses. For weight management, extensive evidence supports LCD as a valid weight loss treatment, up to 1-2 years. Solely lowering carbohydrate intake does not, in the medium/long term, reduce HbA1c for T2D prevention or treatment, as many mechanisms interplay. Under controlled feeding conditions, LCD are not physiologically or clinically superior to diets with higher carbohydrates for weight-loss, fat loss, energy expenditure or glycaemic outcomes; indeed, all metabolic improvements require weight loss. Long-term evidence also links the LCD pattern to increased CVD risks and mortality. LCD can lead to micronutrient deficiencies and increased LDL-cholesterol, depending on food selection to replace carbohydrates. Evidence is limited but promising regarding food choices/sources to replace high-carbohydrate foods that may alleviate the negative effects of LCD, demanding further insight into the dietary practice of medium to long term LCD followers. Long-term, high-quality studies of LCD with different food sources (animal and/or plant origins) are needed, aiming for clinical endpoints (T2D incidence and remission, cardiovascular events, mortality). Ensuring micronutrient adequacy by food selection or supplementation should be considered for people who wish to pursue long-term LCD.
ABSTRACT
This narrative review aims to critically evaluate scientific evidence exploring the therapeutic role(s) of long-chain n-3 PUFA in the context of ageing, and specifically, sarcopenia. We highlight that beyond impairments in physical function and a lack of independence, the age-related decline in muscle mass has ramifications for cardio-metabolic health. Specifically, skeletal muscle is crucial in regulating blood glucose homeostasis (and by extension reducing type 2 diabetes mellitus risk) and providing gluconeogenic precursors that are critical for survival during muscle wasting conditions (i.e. AIDS). Recent interest in the potential anabolic action of n-3 PUFA is based on findings from experimental studies that measured acute changes in the stimulation of muscle protein synthesis (MPS) and/or chronic changes in muscle mass and strength in response to fish oil-derived n-3 PUFA supplementation. Key findings include a potentiated response of MPS to amino acid provision or resistance-based exercise with n-3 PUFA in healthy older adults that extrapolated to longer-term changes in muscle mass and strength. The key mechanism(s) underpinning this enhanced response of MPS remains to be fully elucidated, but is likely driven by the incorporation of exogenous n-3 PUFA into the muscle phospholipid membrane and subsequent up-regulation of cell signalling proteins known to control MPS. In conclusion, multiple lines of evidence suggest that dietary n-3 PUFA provide an essential link between musculoskeletal and cardio-metabolic health in older adults. Given that western diets are typically meagre in n-3 PUFA content, nutritional recommendations for maintaining muscle health with advancing age should place greater emphasis on dietary n-3 PUFA intake.
Subject(s)
Cardiovascular Diseases/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Diet , Fatty Acids, Omega-3 , Adult , Aged , Aged, 80 and over , Aging/physiology , Female , Humans , Male , Middle Aged , Muscle Proteins/metabolism , Muscle, Skeletal/physiology , Risk Factors , SarcopeniaABSTRACT
Plant-based diets rich in bioactive compounds such as polyphenols have been shown to positively modulate the risk of cardiometabolic (CM) diseases. The inter-individual variability in the response to these bioactives may affect the findings. This systematic review aimed to summarize findings from existing randomized clinical trials (RCTs) evaluating the effect of hydroxycinnamic acids (HCAs) on markers of CM health in humans. Literature searches were performed in PubMed and the Web of Science. RCTs on acute and chronic supplementation of HCA-rich foods/extracts on CM biomarkers were included. Forty-four RCTs (21 acute and 23 chronic) met inclusion criteria. Comparisons were made between RCTs, including assessments based on population health status. Of the 44 RCTs, only seven performed analyses on a factor exploring inter-individual response to HCA consumption. Results demonstrated that health status is a potentially important effect modifier as RCTs with higher baseline cholesterol, blood pressure and glycaemia demonstrated greater overall effectiveness, which was also found in studies where specific subgroup analyses were performed. Thus, the effect of HCAs on CM risk factors may be greater in individuals at higher CM risk, although future studies in these populations are needed, including those on other potential determinants of inter-individual variability. PROSPERO, registration number CRD42016050790.
Subject(s)
Biological Variation, Individual , Cardiovascular Diseases/prevention & control , Coumaric Acids/administration & dosage , Diet , Dietary Supplements , Metabolic Diseases/prevention & control , Adult , Aged , Biomarkers/blood , Cardiovascular Diseases/blood , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/physiopathology , Coumaric Acids/adverse effects , Diet/adverse effects , Dietary Supplements/adverse effects , Female , Humans , Male , Metabolic Diseases/blood , Metabolic Diseases/epidemiology , Metabolic Diseases/physiopathology , Middle Aged , Nutritional Status , Nutritive Value , Protective Factors , Randomized Controlled Trials as Topic , Risk Factors , Risk Reduction Behavior , Young AdultABSTRACT
A systematic review of published evidence on micronutrient intake/status with carbohydrate-restricted diets (CRD) was conducted in Web of Science, Medline, Embase, Scopus, CENTRAL, and ClinicalTrials.gov up to October 2018. We identified 10 studies: seven randomized controlled trials (RCTs) ("Atkins"-style, n = 5; "Paleolithic" diets, n = 2), two Atkins-style noncontrolled trials and one cross-sectional study. Prescribed carbohydrate varied 4% to 34% of energy intake. Only one noncontrolled trial prescribed multivitamin supplements. Dietary intakes/status were reported over 2 to 104 weeks, with weight losses from 2 to 9 kg. No diagnoses of deficiency were reported. Intakes of thiamine, folate, magnesium, calcium, iron, and iodine all decreased significantly (-10% to -70% from baseline) with any CRD types. Atkins diet trials (n = 6; 4%-34%E carbohydrate) showed inconsistent changes in vitamin A, E, and ß-carotene intakes, while a single "Paleolithic" diet trial (28%E carbohydrate) reported increases in these micronutrients. One other "Paleolithic" diet (30%E carbohydrate) reported a rise in moderate iodine deficiency from 15% to 73% after 6 months. In conclusion, few studies have assessed the impacts of CRD on micronutrients. Studies with different designs point towards reductions in several vitamins and minerals, with potential risk of micronutrient inadequacies. Trial reporting standards are expected to include analysis of micronutrient intake/status. Micronutrients in foods and/or supplements should be considered when designing, prescribing or following CRDs.
Subject(s)
Diet, Carbohydrate-Restricted , Micronutrients/administration & dosage , Nutritional Status , Body Weight , Energy Intake , HumansABSTRACT
ß-Glucan and black tea are fermented by the colonic microbiota producing short chain fatty acids (SCFA) and phenolic acids (PA). We hypothesized that the addition of ß-glucan, a dietary fiber, and tea polyphenols to a food matrix like bread will also affect starch digestion in the upper gut and thus further influence colonic fermentation and SCFA production. This study investigated SCFA and PA production from locally developed breads: white bread (WB), black tea bread (BT), ß-glucan bread (ßG), ß-glucan plus black tea bread (ßGBT). Each bread was incubated in an in vitro system mimicking human digestion and colonic fermentation. Digestion with α-amylase significantly (p = 0.0001) increased total polyphenol and polyphenolic metabolites from BT bread compared with WB, ßG, and ßGBT. Total polyphenols in ßGBT remained higher (p = 0.016; 1.3-fold) after digestion with pepsin and pancreatin compared with WB. Fermentations containing ßG and ßGBT produced similar propionate concentrations ranging from 17.5 to 18.6 mmol/L and total SCFA from 46.0 to 48.9 mmol/L compared with control WB (14.0 and 37.4 mmol/L, respectively). This study suggests that combination of black tea with ß-glucan in this functional bread did not impact on SCFA production. A higher dose of black tea and ß-glucan or in combination with other fibers may be needed to increase SCFA production.
Subject(s)
Bread , Camellia sinensis , Dietary Fiber/pharmacology , Fatty Acids, Volatile/metabolism , Gastrointestinal Microbiome , beta-Glucans/pharmacology , Fermentation , HumansABSTRACT
Iodine is essential for thyroid hormones synthesis and normal neurodevelopment; however, ~60% of pregnant women do not meet the WHO (World Health Organization) recommended intake. Using a qualitative design, we explored the perceptions, awareness, and experiences of pregnancy nutrition, focusing on iodine. Women in the perinatal period (n = 48) were interviewed and filled in a food frequency questionnaire for iodine. Almost all participants achieved the recommended 150 µg/day intake for non-pregnant adults (99%), but only 81% met the increased demands of pregnancy (250 µg/day). Most were unaware of the importance, sources of iodine, and recommendations for iodine intake. Attitudes toward dairy products consumption were positive (e.g., helps with heartburn; easy to increase). Increased fish consumption was considered less achievable, with barriers around taste, smell, heartburn, and morning sickness. Community midwives were the main recognised provider of dietary advice. The dietary advice received focused most often on multivitamin supplements rather than food sources. Analysis highlighted a clear theme of commitment to change behaviour, motivated by pregnancy, with a desired focus on user-friendly documentation and continued involvement of the health services. The study highlights the importance of redirecting advice on dietary requirements in pregnancy and offers practical suggestions from women in the perinatal period as the main stakeholder group.
Subject(s)
Diet , Dietary Supplements , Iodine/administration & dosage , Maternal Nutritional Physiological Phenomena , Nutritional Status , Recommended Dietary Allowances , Adult , Attitude of Health Personnel , Cross-Sectional Studies , Dairy Products , Diet/adverse effects , Feeding Behavior , Female , Health Behavior , Health Knowledge, Attitudes, Practice , Humans , Interviews as Topic , Nutritive Value , Pregnancy , Qualitative Research , SeafoodABSTRACT
Understanding interindividual variability in response to dietary polyphenols remains essential to elucidate their effects on cardiometabolic disease development. A meta-analysis of 128 randomized clinical trials was conducted to investigate the effects of berries and red grapes/wine as sources of anthocyanins and of nuts and pomegranate as sources of ellagitannins on a range of cardiometabolic risk biomarkers. The potential influence of various demographic and lifestyle factors on the variability in the response to these products were explored. Both anthocyanin- and ellagitannin-containing products reduced total-cholesterol with nuts and berries yielding more significant effects than pomegranate and grapes. Blood pressure was significantly reduced by the two main sources of anthocyanins, berries and red grapes/wine, whereas waist circumference, LDL-cholesterol, triglycerides, and glucose were most significantly lowered by the ellagitannin-products, particularly nuts. Additionally, we found an indication of a small increase in HDL-cholesterol most significant with nuts and, in flow-mediated dilation by nuts and berries. Most of these effects were detected in obese/overweight people but we found limited or non-evidence in normoweight individuals or of the influence of sex or smoking status. The effects of other factors, i.e., habitual diet, health status or country where the study was conducted, were inconsistent and require further investigation.
Subject(s)
Anthocyanins/chemistry , Anthocyanins/pharmacology , Biomarkers , Diet , Energy Metabolism/drug effects , Food , Hydrolyzable Tannins/chemistry , Hydrolyzable Tannins/pharmacology , Myocardium/metabolism , Anthocyanins/adverse effects , Cardiovascular Diseases/etiology , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/physiopathology , Cardiovascular Physiological Phenomena/drug effects , Cardiovascular System/drug effects , Dietary Supplements , Humans , Hydrolyzable Tannins/adverse effects , Risk FactorsABSTRACT
Several epidemiological studies have linked flavonols with decreased risk of cardiovascular disease (CVD). However, some heterogeneity in the individual physiological responses to the consumption of these compounds has been identified. This meta-analysis aimed to study the effect of flavonol supplementation on biomarkers of CVD risk such as, blood lipids, blood pressure and plasma glucose, as well as factors affecting their inter-individual variability. Data from 18 human randomized controlled trials were pooled and the effect was estimated using fixed or random effects meta-analysis model and reported as difference in means (DM). Variability in the response of blood lipids to supplementation with flavonols was assessed by stratifying various population subgroups: age, sex, country, and health status. Results showed significant reductions in total cholesterol (DM = -0.10 mmol/L; 95% CI: -0.20, -0.01), LDL cholesterol (DM = -0.14 mmol/L; Nutrients 2017, 9, 117 2 of 21 95% CI: -0.21, 0.07), and triacylglycerol (DM = -0.10 mmol/L; 95% CI: -0.18, 0.03), and a significant increase in HDL cholesterol (DM = 0.05 mmol/L; 95% CI: 0.02, 0.07). A significant reduction was also observed in fasting plasma glucose (DM = -0.18 mmol/L; 95%CI: -0.29, -0.08), and in blood pressure (SBP: DM = -4.84 mmHg; 95% CI: -5.64, -4.04; DBP: DM = -3.32 mmHg; 95% CI: -4.09, -2.55). Subgroup analysis showed a more pronounced effect of flavonol intake in participants from Asian countries and in participants with diagnosed disease or dyslipidemia, compared to healthy and normal baseline values. In conclusion, flavonol consumption improved biomarkers of CVD risk, however, country of origin and health status may influence the effect of flavonol intake on blood lipid levels.
Subject(s)
Cardiovascular Diseases/prevention & control , Dietary Supplements , Flavonols/administration & dosage , Adult , Asia , Biomarkers/blood , Blood Pressure , Cardiovascular Diseases/etiology , Cholesterol/blood , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Female , Humans , Lipids/blood , Male , Middle Aged , Randomized Controlled Trials as Topic , Risk FactorsABSTRACT
Polyphenols have been extensively studied for their antioxidant and anti-inflammatory properties. Recently, their antiglycative actions by oxidative stress modulation have been linked to the prevention of diabetes and associated complications. This article assesses the evidence for polyphenol interventions on glycohemoglobin (HbA1c) in non-diabetic, pre-diabetic, and type 2 diabetes mellitus (T2DM) subjects. A systematic review of polyphenols' clinical trials on HbA1c in humans was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis. Thirty-six controlled randomized trials with HbA1c values were included. Polyphenols (extracts, supplements, and foods) were supplemented (28 mg to 1.5 g) for 0.7 to 12 months. Combining all subjects (n = 1954, mean baseline HbA1c = 7.03%, 53 mmol/mol), polyphenol supplementation significantly (P < 0.001) lowered HbA1c% by -0.53 ± 0.12 units (-5.79 ± 0.13 mmol/mol). This reduction was significant (P < 0.001) in T2DM subjects, specifically (n = 1426, mean baseline HbA1c = 7.44%, 58 mmol/mol), with HbA1c% lowered by -0.21 ± 0.04 units (-2.29 ± 0.4 mmol/mol). Polyphenol supplementation had no significant effect (P > 0.21) in the non-diabetic (n = 258, mean baseline HbA1c = 5.47%, 36 mmol/mol) and the pre-diabetic subjects (n = 270, mean baseline HbA1c = 6.06%, 43 mmol/mol) strata: -0.39 ± 0.27 HbA1c% units (-4.3 ± 0.3 mmol/mol), and -0.38 ± 0.31 units (-4.2 ± 0.31 mmol/mol), respectively. In conclusion, polyphenols can successfully reduce HbA1c in T2DM without any intervention at glycemia, and could contribute to the prevention of diabetes complications.
Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin/metabolism , Polyphenols/administration & dosage , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Blood Glucose/metabolism , Diabetes Complications/prevention & control , Diabetes Mellitus, Type 2/blood , Dietary Supplements , Humans , Randomized Controlled Trials as TopicABSTRACT
Bread and tea are usually consumed separately, but there may be different food-matrix interactions and changes in starch characteristics when they are combined in bread. This study developed breads (white bread, WF; black tea, BT; beta glucan, ßG; beta glucan plus black tea, ßGBT) and determined their starch functionalities. Breads were developed using a standard baking recipe and determined their starch characteristics. There was no significant difference in starch hydrolysis between BT and WF but ßGBT reduced early (10 min) starch hydrolysis compared with ßG. The starch granules in ßG and ßGBT were elliptical and closely packed together. These results suggest that the addition of beta glucan and black tea to bread preserved the elliptical starch granules and lowered short-term starch hydrolysis.
Subject(s)
Bread/analysis , Camellia sinensis , Food Handling/methods , Starch/metabolism , Tea , Triticum , beta-Glucans , Blood Glucose/metabolism , Dietary Fiber , Flour/analysis , Functional Food , Humans , HydrolysisABSTRACT
BACKGROUND: Olive oil (OO) consumption is associated with cardiovascular disease prevention because of both its oleic acid and phenolic contents. The capacity of OO phenolics to protect against low-density lipoprotein (LDL) oxidation is the basis for a health claim by the European Food Safety Authority. Proteomic biomarkers enable an early, presymptomatic diagnosis of disease, which makes them important and effective, but understudied, tools for primary prevention. OBJECTIVE: We evaluated the impact of supplementation with OO, either low or high in phenolics, on urinary proteomic biomarkers of coronary artery disease (CAD), chronic kidney disease (CKD), and diabetes. DESIGN: Self-reported healthy participants (n = 69) were randomly allocated (stratified block random assignment) according to age and body mass index to supplementation with a daily 20-mL dose of OO either low or high in phenolics (18 compared with 286 mg caffeic acid equivalents per kg, respectively) for 6 wk. Urinary proteomic biomarkers were measured at baseline and 3 and 6 wk alongside blood lipids, the antioxidant capacity, and glycation markers. RESULTS: The consumption of both OOs improved the proteomic CAD score at endpoint compared with baseline (mean improvement: -0.3 for low-phenolic OO and -0.2 for high-phenolic OO; P < 0.01) but not CKD or diabetes proteomic biomarkers. However, there was no difference between groups for changes in proteomic biomarkers or any secondary outcomes including plasma triacylglycerols, oxidized LDL, and LDL cholesterol. CONCLUSION: In comparison with low-phenolic OO, supplementation for 6 wk with high-phenolic OO does not lead to an improvement in cardiovascular health markers in a healthy cohort.
Subject(s)
Coronary Artery Disease/prevention & control , Diabetic Nephropathies/prevention & control , Diet, Mediterranean , Functional Food , Plant Oils/therapeutic use , Proteinuria/prevention & control , Renal Insufficiency, Chronic/prevention & control , Adolescent , Adult , Biomarkers/urine , Case-Control Studies , Cohort Studies , Coronary Artery Disease/epidemiology , Coronary Artery Disease/physiopathology , Coronary Artery Disease/urine , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 1/prevention & control , Diabetes Mellitus, Type 1/urine , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/prevention & control , Diabetes Mellitus, Type 2/urine , Diabetic Nephropathies/complications , Double-Blind Method , Female , Functional Food/analysis , Humans , Male , Olive Oil , Phenols/analysis , Phenols/therapeutic use , Plant Oils/chemistry , Proteinuria/etiology , Renal Insufficiency, Chronic/epidemiology , Renal Insufficiency, Chronic/physiopathology , Renal Insufficiency, Chronic/urine , Risk Factors , Scotland/epidemiology , Young AdultABSTRACT
Iodine insufficiency is now a prominent issue in the UK and other European countries due to low intakes of dairy products and seafood (especially where iodine fortification is not in place). In the present study, we tested a commercially available encapsulated edible seaweed (Napiers Hebridean Seagreens® Ascophyllum nodosum species) for its acceptability to consumers and iodine bioavailability and investigated the impact of a 2-week daily seaweed supplementation on iodine concentrations and thyroid function. Healthy non-pregnant women of childbearing age, self-reporting low dairy product and seafood consumption, with no history of thyroid or gastrointestinal disease were recruited. Seaweed iodine (712 µg, in 1 g seaweed) was modestly bioavailable at 33 (interquartile range (IQR) 28-46) % of the ingested iodine dose compared with 59 (IQR 46-74) % of iodine from the KI supplement (n 22). After supplement ingestion (2 weeks, 0·5 g seaweed daily, n 42), urinary iodine excretion increased from 78 (IQR 39-114) to 140 (IQR 103-195) µg/l (P< 0·001). The concentrations of thyroid-stimulating hormone increased from 1·5 (IQR 1·2-2·2) to 2·1 (IQR 1·3-2·9) mIU/l (P< 0·001), with two participants having concentrations exceeding the normal range after supplement ingestion (but normal free thyroxine concentrations). There was no change in the concentrations of other thyroid hormones after supplement ingestion. The seaweed was palatable and acceptable to consumers as a whole food or as a food ingredient and effective as a source of iodine in an iodine-insufficient population. In conclusion, seaweed inclusion in staple foods would serve as an alternative to fortification of salt or other foods with KI.
Subject(s)
Iodine/administration & dosage , Iodine/deficiency , Nutritional Status , Seaweed/chemistry , Adult , Biological Availability , Dairy Products , Dietary Supplements , Female , Humans , Iodine/pharmacokinetics , Patient Satisfaction , Scotland , Seafood , Thyroid Hormones/blood , Thyrotropin/blood , Thyroxine/bloodABSTRACT
Protein glycation has been studied for over a century now and plays an important role in disease pathogenesis throughout the lifecycle. Strongly related to diabetic complications, glycation of Hb has become the gold standard method for diabetes diagnosis and monitoring. It is however attracting attention in normoglycaemia as well lately. Longitudinal studies increasingly suggest a positive relationship between glycation and the risk of chronic diseases in normoglycaemic individuals, but the mechanisms behind this association remain unclear. The interaction between glycation and oxidative stress may be particularly relevant in the normoglycaemic context, as suggested by recent epidemiological and in vitro evidence. In that context nutritional and lifestyle factors with an influence on redox status, such as smoking, fruit and vegetable and antioxidants consumption, may have the capacity to promote or inhibit glycation. However, experimental data from controlled trials are lacking the quality and rigour needed to reach firm conclusions. In the present review, we discuss the importance of glycation for health through the lifecycle and focus on the importance of oxidative stress as a driver for glycation. The importance of nutrition to modulate glycation is discussed, based on the evidence available and recommendations towards higher quality future research are made.
Subject(s)
Antioxidants/therapeutic use , Diabetes Mellitus/metabolism , Diet , Glycated Hemoglobin/metabolism , Glycation End Products, Advanced/metabolism , Maillard Reaction , Oxidative Stress , Diabetes Complications/etiology , Diabetes Complications/metabolism , Diabetes Complications/prevention & control , Diabetes Mellitus/diagnosis , HumansABSTRACT
Nitrite has long been considered a potential pre-carcinogen for gastric cancer. Acidification of salivary nitrite, derived from dietary nitrate, produces nitrosative species such as NOSCN, NO(+) and N(2)O(3), which can form potentially carcinogenic N-nitroso compounds. Ascorbic acid inhibits nitrosation by converting the nitrosative species into nitric oxide (NO). However, NO diffuses rapidly to adjacent lipids, where it reacts with oxygen to reform nitrosative species. Nitrosation has been studied in vitro in aqueous systems and less frequently in organic systems; however, there is a need to investigate acid-catalysed nitrosation in a system combining aqueous and lipid environments, hence providing a physiologically relevant model. Here, we describe a two-phase system, which can be used as a tool to understand acid-catalysed nitrosation. Using gas chromatography/ion trap tandem mass spectrometry, we investigated the nitrosation of secondary amines as a function of the lipid phase composition and reaction mixing. An increased interface surface area was a driver for nitrosation, while incorporation of unsaturated fatty acids affected morpholine and piperidine nitrosation differently. Linoleic acid methyl esters did not affect morpholine nitrosation and only had a limited effect on N-nitrosopiperidine formation, while incorporation of free linoleic acid to the lipid phase significantly reduced N-nitrosopiperidine formation, but increased N-nitrosomorpholine formation at low levels. The mechanisms driving these effects are thought to involve amine partitioning, polarity and unsaturated fatty acids acting as scavengers of nitrosating species, findings relevant to the nitrosative chemistry occurring in the stomach, where the gastric acid meets a range of dietary fats which are emulsified during digestion.