Exploring relationships with food after dietary intervention in patients with colorectal cancer: a qualitative analysis from the Protein Recommendations to Increase Muscle (PRIMe) trial.

PURPOSE: Patients with cancer often experience nutritional challenges and are vulnerable to muscle mass loss. While substantial research is directed towards understanding how nutritional interventions affect clinical outcomes, insights into patients' personal experiences during these trials remain limited. This qualitative study aimed to gain a deeper understanding of how participation in the Protein Recommendations to Increase Muscle (PRIMe) trial affected patients' relationships with food. METHODS: A subset of patients who completed a minimum of one follow-up visit in the PRIMe trial participated in a semi-structured interview about their experience implementing dietary modifications to increase protein intake. Data from 26 patients with a recent diagnosis of stage II-IV colorectal cancer (non-cachectic) were included. Interviews were audio recorded, transcribed verbatim, and qualitative content analysis was applied. RESULTS: Most patients were male (65.4%) with stage II or III (69.2%) colorectal cancer and were a mean age of 57 ± 10 years. Five key themes emerged to provide a deeper understanding of patients' relationship with food after the PRIMe trial: (1) new positive perspectives on nutrition and coping with a cancer diagnosis; (2) embracing a comprehensive approach to food and nutrition; (3) facilitators promoting adherence to the intervention; (4) barriers challenging adherence to the intervention; and (5) shaping future dietary intake. CONCLUSION: This qualitative study explored the emotional and psychological effects of a clinical nutrition trial on patients, focusing on their relationship with food. It underscored the trial's comprehensive intervention and its enduring influence on patients, extending beyond the immediate intervention phase. The role of current perspectives, motivation, and knowledge acquisition on ability to adhere to dietary changes to increase protein intake were emphasized by patients and are key considerations for both clinicians and researchers. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02788955; registration posted on 2016-06-02.

Population attributable fractions of modifiable risk factors for dementia: a systematic review and meta-analysis.

BACKGROUND: More than 57 million people have dementia worldwide. Evidence indicates a change in dementia prevalence and incidence in high-income countries, which is likely to be due to improved life-course population health. Identifying key modifiable risk factors for dementia is essential for informing risk reduction and prevention strategies. We therefore aimed to estimate the population attributable fraction (PAF) for dementia associated with modifiable risk factors. METHODS: In this systematic review and meta-analysis, we searched Embase, MEDLINE, and PsycINFO, via Ovid, from database inception up to June 29, 2023, for population-derived or community-based studies and reviews reporting a PAF value for one or more modifiable risk factor for later-life dementia (prevalent or incident dementia in people aged ≥60 years), with no restrictions on dementia subtype, the sex or baseline age of participants, or the period of study. Articles were independently screened for inclusion by four authors, with disagreements resolved through consensus. Data including unweighted and weighted PAF values (weighted to account for communality or overlap in risk) were independently extracted into a predefined template by two authors and checked by two other authors. When five or more unique studies investigated a given risk factor or combination of the same factors, random-effects meta-analyses were used to calculate a pooled PAF percentage estimate for the factor or combination of factors. The review protocol was registered on PROSPERO, CRD42022323429. FINDINGS: 4024 articles were identified, and 74 were included in our narrative synthesis. Overall, PAFs were reported for 61 modifiable risk factors, with sufficient data available for meta-analysis of 12 factors (n=48 studies). In meta-analyses, the highest pooled unweighted PAF values were estimated for low education (17·2% [95% CI 14·4-20·0], p<0·0001), hypertension (15·8% [14·7-17·1], p<0·0001), hearing loss (15·6% [10·3-20·9], p<0·0001), physical inactivity (15·2% [12·8-17·7], p<0·0001), and obesity (9·4% [7·3-11·7], p<0·0001). According to weighted PAF values, low education (9·3% [6·9-11·7], p<0·0001), physical inactivity (7·3% [3·9-11·2], p=0·0021), hearing loss (7·2% [5·2-9·7], p<0·0001), hypertension (7·1% [5·4-8·8], p<0·0001), and obesity (5·3% [3·2-7·4], p=0·0001) had the highest pooled estimates. When low education, midlife hypertension, midlife obesity, smoking, physical inactivity, depression, and diabetes were combined (Barnes and Yaffe seven-factor model; n=9 studies), the pooled unweighted and weighted PAF values were 55·0% (46·5-63·5; p<0·0001) and 32·0% (26·6-37·5; p<0·0001), respectively. The pooled PAF values for most individual risk factors were higher in low-income and middle-income countries (LMICs) versus high-income countries. INTERPRETATION: Governments need to invest in a life-course approach to dementia prevention, including policies that enable quality education, health-promoting environments, and improved health. This investment is particularly important in LMICs, where the potential for prevention is high, but resources, infrastructure, budgets, and research focused on ageing and dementia are limited. FUNDING: UK Research and Innovation (Medical Research Council).

Advancing body composition assessment in patients with cancer: First comparisons of traditional versus multicompartment models.

BACKGROUND AND AIMS: Measurement of body composition using computed tomography (CT) scans may be a viable clinical tool for low muscle mass assessment in oncology. However, longitudinal assessments are often infeasible with CT. Clinically accessible body composition technologies can be used to track changes in fat-free mass (FFM) or muscle, though their accuracy may be impacted by cancer-related physiological changes. The purpose of this study was to examine the agreement among accessible body composition method with criterion methods for measures of whole-body FFM measurements and, when possible, muscle mass for the classification of low muscle in patients with cancer. METHODS: Patients with colorectal cancer were recruited to complete measures of whole-body DXA, air displacement plethysmography (ADP), and bioelectrical impedance analysis (BIA). These measures were used alone, or in combination to construct the criterion multicompartment (4C) mode for estimating FFM. Patients also underwent abdominal CT scans as part of routine clinical assessment. Agreement of each method with 4C model was analyzed using mean constant error (CE = criterion - alternative), linear regression including root mean square error (RMSE), Bland-Altman limits of agreement (LoA) and mean percentage difference (MPD). Additionally, appendicular lean soft tissue index (ALSTI) measured by DXA and predicted by CT were compared for the absolute agreement, while the ALSTI values and skeletal muscle index by CT were assessed for agreement on the classification of low muscle mass. RESULTS: Forty-five patients received all measures for the 4C model and 25 had measures within proximity of clinical CT measures. Compared to 4C, DXA outperformed ADP and BIA by showing the strongest overall agreement (CE = 1.96 kg, RMSE = 2.45 kg, MPD = 98.15 ± 2.38%), supporting its use for body composition assessment in patients with cancer. However, CT cutoffs for skeletal muscle index or CT-estimated ALSTI were lower than DXA ALSTI (average 1.0 ± 1.2 kg/m2) with 24.0% to 32.0% of patients having a different low muscle classification by CT when compared to DXA. CONCLUSIONS: Despite discrepancies between clinical body composition assessment and the criterion multicompartment model, DXA demonstrates the strongest agreement with 4C. Disagreement between DXA and CT for low muscle mass classification prompts further evaluation of the measures and cutoffs used with each technique. Multicompartment models may enhance our understanding of body composition variations at the individual patient level and improve the applicability of clinically accessible technologies for classification and monitoring change over time.

Assessing Sodium Intake in Middle-Aged and Older Adults with Elevated Blood Pressure: Validation of Spot Urine Excretion and Dietary Survey-Derived Estimates.

This cross-sectional study evaluated the validity of three alternative methods compared to the gold standard 24-h urine collection for estimating dietary sodium intake, a modifiable risk factor for hypertension, among middle-aged and older adults with elevated blood pressure. These included spot urine collection (using Kawasaki, Tanaka, and INTERSALT equations), 24-h dietary recall, and food frequency questionnaire responses, compared to 24-h urine collection in a subset of 65 participants (aged 50-75 years, 58.5% women, 61.6% hypertensive) from the DePEC-Nutrition trial. The validity of the methods was assessed using bias, the Spearman correlation coefficient (SCC), the intraclass correlation coefficient (ICC), and Bland-Altman analysis. Among the alternative methods, spot urine collection using the Kawasaki equation showed the strongest correlation (SCC 0.238; ICC 0.119, 95% CI -0.079 to 0.323), but it exhibited a significant bias (1414 mg/day, p-value < 0.001) relative to 24-h urine collection. Conversely, dietary surveys had a smaller bias but wider limits of agreement. These findings underscore the complexities of accurately estimating dietary sodium intake using spot urine collection or dietary surveys in this specific population, suggesting that a combination or the refinement of existing methodologies might improve accuracy. Further research with larger samples is necessary to develop more reliable methods for assessing sodium intake in this high-risk group.

Associations between Vegetable Nitrate Intake and Cardiovascular Disease Risk and Mortality: A Systematic Review.

Consumption of nitrate-rich vegetables increases nitric oxide bioavailability, lowers blood pressure, and improves endothelial function. These effects could also translate into reduced cardiovascular disease (CVD) risk and mortality. This systematic review aimed to investigate the associations between habitual vegetable nitrate intake and CVD incidence and mortality. A secondary aim was to identify factors that moderate the relationship between vegetable nitrate intake and CVD incidence/mortality. Seven databases (PubMed, MEDLINE, Embase, Scopus, Web of Science, CINAHL, and APA PsycINFO) were searched from inception to 13 February 2023. Observational studies quantifying vegetable nitrate intake in participants aged 18+ years through self-reported dietary exposure and assessing incidence or mortality from CVD overall, or individual CVD subtypes, were eligible. Five studies including a total of 63,155 participants were included. There was an inverse association between vegetable nitrate intake and most reported CVD outcomes. Reported risk reductions tended to plateau at moderate intake, suggesting a possible ceiling effect. The risk of bias across all studies was low. The results of this systematic review suggest a potential role for vegetable nitrate in reducing CVD risk and mortality. Further randomised controlled trials are now required to corroborate these findings.

Effects of the COVID-19 associated United Kingdom lockdown on physical activity in older adults at high risk of cardiovascular disease: a mixed methods perspective from the MedEx-UK multicenter trial.

Introduction: Physical inactivity and sedentary behaviour are linked to increased risk of cardiovascular disease, infections and dementia, as well as placing a significant economic burden on healthcare systems. The implementation of COVID-19 pandemic lockdown measures aimed at reducing virus transmission posed challenges to the opportunity to be physically active. This study investigates how the first UK COVID-19 lockdown affected objectively measured physical activity in older adults at higher risk of cardiovascular disease. Methods: We studied 48 individuals aged 55-74 years (81.3% female) with self-reported PA levels < 90 min/week and a QRISK2 score ≥ 10 (indicative of a ≥ 10% risk of a major cardiovascular event in the next 10 years) without mild cognitive impairment or dementia. Physical activity data was collected using objective wrist-based activity monitors and analysed across three time periods, usual activity (pre-pandemic), the precautionary phase when the UK began advising on limiting social contact and finally during the first UK lockdown period was collected (27 January 2020 and 07 June 2020). Data was analysed using linear mixed effects model was used to investigate PA levels over the measured 12-week period. Effects of BMI, age, deprivation score and baseline PA levels on PA across the three measurement periods were also examined. Focus-group and individual interviews were conducted, and data were thematically analysed. Results: Average daily step count (-34% lower, p < 0.001) and active energy expenditure (-26% lower, p < 0.001) were significantly lower during the precautionary period compared with the usual activity period. Physical activity remained low during the UK lockdown period. Participants with a lower BMI engaged in significantly more (+45% higher daily steps p < 0.001) physical activity and those over 70 years old were more physically active than those under 70 years across the 12-week period (+23% higher daily steps p < 0.007). The risk of COVID-19 infection and restrictions because of lockdown measures meant some individuals had to find alternative methods to staying physical active. Participants described a lack of access to facilities and concerns over health related to COVID-19 as barriers to engaging in physical activity during lockdown. For some, this resulted in a shift towards less structured activities such as gardening or going for a walk. Discussion: The data presented shows that lockdown measures during the COVID-19 pandemic significantly reduced physical activity among older individuals at risk of cardiovascular disease, particularly those with a higher body mass index. To support this population group in staying active during future lockdowns, a multifaceted strategy is needed, emphasizing psychosocial benefits and home-based physical activity. The MedEx-UK study was pre-registered with ClinicalTrials.gov (NCT03673722).

Higher plant-derived nitrate intake is associated with lower odds of frailty in a cross-sectional study of community-dwelling older women.

PURPOSE: Dietary nitrate intake is inversely related to numerous contributors towards frailty, including cardiovascular disease and poor physical function. Whether these findings extend to frailty remain unknown. We investigated if habitual nitrate intake, derived from plants or animal-based foods, was cross-sectionally associated with frailty in women. METHODS: Community-dwelling older Australian women (n = 1390, mean age 75.1 ± 2.7 years) completed a validated semi-quantitative food frequency questionnaire (FFQ). Nitrate concentrations in food were obtained from international nitrate databases. We adopted the Rockwood frailty index (FI) of cumulative deficits comprising 33 variables across multiple health domains (scored 0 to 1), which predicts increased hospitalisation and mortality risk. A FI ≥ 0.25 indicated frailty. Cross-sectional associations between nitrate intake (total plant and animal nitrate, separately) and frailty were analysed using multivariable-adjusted logistic regression models (including lifestyle factors), as part of restricted cubic splines. RESULTS: A non-linear inverse relationship was observed between total plant nitrate intake and frailty. Compared to women with the lowest plant nitrate intake (Quartile [Q]1), women with greater intakes in Q2 (OR 0.69 95%CI 0.56-0.84), Q3 (OR 0.67 95%CI 0.50-0.90) and Q4 (OR 0.66 95%CI 0.45-0.98) had lower odds for frailty. A nadir in the inverse association was observed once intakes reached ~ 64 mg/d (median Q2). No relationship was observed between total animal nitrate and frailty. CONCLUSION: Community-dwelling older women consuming low amounts of plant-derived nitrate were more likely to present with frailty. Consuming at least one daily serving (~ 75 g) of nitrate-rich green leafy vegetables may be beneficial in preventing frailty.

Effects of dietary nitrate supplementation on oral health and associated markers of systemic health: a systematic review.

Poor oral health can impact an individual's ability to eat and has been associated with an increased risk of non-communicable diseases. While the benefits of nitrate consumption on oral health were first proposed more than 20 years ago, no systematic review has been published examining effects of dietary nitrate on oral health. This systematic review investigated the effects of dietary nitrate on markers of oral health in vivo in randomized controlled trials (RCTs). Five databases (PubMed, The Cochrane Library, CINAHL, MEDLINE, and SPORTDiscus) were searched from inception until March 2023. Nine articles reporting data on 284 participants were included. Dietary nitrate was provided via beetroot juice in most studies. The duration of the interventions ranged from one day to six weeks. Dietary nitrate supplementation increased the relative abundance of several individual bacterial genera including Neisseria and Rothia. Dietary nitrate supplementation increased salivary pH and decreased salivary acidification following consumption of a sugar-sweetened beverage. Furthermore, dietary nitrate supplementation resulted in a decrease in the gingival inflammation index. The results of this systematic review suggest that dietary nitrate could represent a potential nutritional strategy to positively modify oral health by impacting the oral microbiome, altering salivary pH, and minimizing gingival inflammation.

Body Composition, Sarcopenic Obesity, and Cognitive Function in Older Adults: Findings From the National Health and Nutrition Examination Survey (NHANES) 1999-2002 and 2011-2014.

OBJECTIVE: Sarcopenic-obesity (SO) is characterized by the concomitant presence of low muscle mass and high adiposity. This study explores the association of body composition and SO phenotypes with cognitive function in older adults. METHODS: Cross-sectional data in older adults (≥60 years) from NHANES 1999-2002 and 2011-2014 were used. In the 1999-2002 cohort, phenotypes were derived from body mass index (BMI) and dual-X-ray-absorptiometry, and cognition was assessed the by Digit-Symbol-Substitution-Test (DSST). In the 2011-2014 cohort, phenotypes were derived from BMI, waist-circumference (WC), and hand-grip-strength (HGS). Cognition was assessed using four tests: DSST, Animal Fluency, the Consortium-to-Establish-a-Registry-for-Alzheimer's-Disease-Delayed-Recall, and Word Learning. Mediation analysis was conducted to evaluate the contribution of inflammation (C-reactive-protein, CRP) and insulin resistance (Homeostatic-Model-Assessment-for-Insulin-Resistance, HOMA-IR) to the association between body composition and cognitive outcomes. RESULTS: The SO phenotype had the lowest DSST mean scores (p < 0.05) and was associated with a significant risk of cognitive impairment [Odds Ratio (OR) = 1.9; 95%CI 1.0-3.7, p = 0.027] in the 1999-2002 cohort. A higher ratio of fat mass and fat free mass (FM/FFM) also showed a greater risk of cognitive impairment (OR = 2.0; 95%CI 1.3-3.1, p = 0.004). In the 2011-2014 cohort, the high WC-Low HGS group showed significantly lower scores on all four cognitive tests (p < 0.05) and a higher risk of cognitive impairment. CRP and HOMA-IR were significant partial mediators of the association between FM/FFM and DSST in the 1999-2002 cohort. CONCLUSIONS: The SO phenotype was associated with a higher risk of cognitive impairment in older adults. Insulin resistance and inflammation may represent key mechanisms linking SO to the development of cognitive impairment.

Association between body mass index and age of disease onset with clinical outcomes in paediatric-onset Crohn's Disease (CD): a UK nation-wide analyses using the NIHR-IBD BioResource.

BACKGROUND: The evidence on the relationship between adiposity and disease outcomes in paediatric Crohn's disease (CD) is limited and lacks consensus. AIM: To investigate the relationship between (a) body mass index (BMI) and clinical CD outcomes (hospitalisation, surgery, disease behaviour, biologic use, extra-intestinal manifestations (EIMs)) and (b) the age of CD onset with clinical outcomes. DESIGN: Clinical outcomes were examined in CD patients diagnosed at age <17 years and enroled in the National Institute for Health Research IBD-UK BioResource at a median age of 24 years. All outcomes and BMI were recorded at the time of enrolment. Participants were categorised into normal (<25 kg/m2) and high (≥25 kg/m2) BMI. Age at disease diagnosis was categorised into pre-puberty/early puberty (<11 years), puberty (11-14 years) and post-puberty (15-17 years). Spearman rank correlation was used to test the associations between continuous variables and chi-square test to compare categorical variables. RESULTS: 848 participants with CD were included (51.8% males) and median age at diagnosis was 14 years. Participants with high BMI experienced a greater frequency of EIMs (P = 0.05) than those with low BMI (1 type of EIM: 18.5% vs. 13.2%, respectively; ≥2 types of EIMs: 7.8% vs. 5.6%, respectively). Age at diagnosis and BMI showed weak correlations with corticosteroid use (ρ = 0.08, P = 0.03 and ρ = -0.09, P = 0.01; respectively). An early diagnosis (<11 years) was associated with higher occurrence of stenosing and penetrating disease behaviour (P = 0.01) and hospitalisations (P < 0.001). CONCLUSIONS: A higher BMI and an earlier age of disease onset are associated with worse CD clinical presentation.

Examining Sociodemographic Factors, Reasons, and Barriers in the Diversity of Fruit and Vegetable Intake among Undergraduate Students.

The transition from adolescence to university life represents a crucial period during which dietary choices can significantly influence long-term health outcomes. While the benefits of consuming a diet rich in fruits and vegetables (FVs) are widely acknowledged, there remains a noticeable gap in research concerning the factors influencing the consumption of specific FV varieties among university students. This study aimed to investigate the factors and barriers influencing the diversity of fruit and vegetable intake among undergraduate students. A cross-sectional study involving 542 undergraduate students (with an average age of 20.6 ± 0.1 years and a body mass index of 21.3 ± 0.2 kg/m2) was conducted at Chulalongkorn University in Bangkok, Thailand, between February and September 2022. Most students showed a preference for tropical fruits with inedible peels (88.2%) and Brassicaceae vegetables (91.0%), whereas lower consumption was observed for citrus fruits (19.7%) and Fabaceae vegetables (43.7%). Sociodemographic factors and cooking methods significantly influenced FV intake, with non-consumption associated with male students, independent living, lower BMI, and advanced academic years. A lower quality of life was found to be correlated with a higher proportion of students who did not consume vegetables. Barriers to inadequate fruit intake included busy lifestyles, while taste preference emerged as the primary reason for fruit consumption. Busy lifestyles and perceived healthiness were identified as the main barriers and reasons for vegetable intake. The study highlights the importance of implementing strategies and improvements in the university environment to promote diverse FV consumption and encourage healthy dietary behaviors among students.

Sarcopenic obesity in older adults: a clinical overview.

Sarcopenic obesity is characterized by a concurrent decline in muscle mass and function, along with increased adipose tissue. Sarcopenic obesity is a growing concern in older adults owing to significant health consequences, including implications for mortality, comorbidities and risk of developing geriatric syndromes. A 2022 consensus statement established a new definition and diagnostic criteria for sarcopenic obesity. The pathophysiology of this condition involves a complex interplay between muscle, adipose tissue, hormonal changes, inflammation, oxidative stress and lifestyle factors, among others. Sarcopenic obesity is treated with a range of management approaches, such as lifestyle interventions, exercise, nutrition and medical therapies. Emerging therapies that were developed for treating other conditions may be relevant to sarcopenic obesity, including novel pharmacological agents and personalized approaches such as precision medicine. In this Review, we synthesize the current knowledge of the clinical importance of sarcopenic obesity, its assessment and diagnosis, along with current and emerging management strategies.

Dietary nitrate intake and association with markers of cardiometabolic risk in Iranian female adolescents.

Dietary nitrates are thought to confer several cardiometabolic health benefits, including improvements in blood pressure and the plasma lipid profile. However, existing data from Iran is conflicting and there is a dearth of literature focusing on non-adult populations. A total of 988 adolescent girls were recruited from schools in different areas of Mashhad and Sabzevar, Iran. Dietary nitrate intake was assessed using a food frequency questionnaire and participants were categorized into quartiles based on this. Differences in participant characteristics between quartiles were assessed using one-way ANOVA and associations between total nitrate intake, nitrate intake from vegetables and cardiometabolic risk markers (blood lipid profile, fasting blood glucose, systolic and diastolic blood pressure) were assessed using linear regression. Nitrate intake from vegetables was positively correlated with triglycerides, even after adjusting for several variables (ß = 0.086, 95% CI = 0.002-0.097; P = 0.043). Total nitrate intake was also significantly positively associated with serum triglycerides (ß = 0.097, 95% CI = 0.010-0.084; P = 0.012); however, this relationship disappeared after adjusting for several variables. Significant interaction effects were observed between total nitrate intake, nitrate intake from vegetables, and vitamin C upon triglycerides (P < 0.01). No significant relationships were found between total nitrate intake, nitrate intake from vegetables, and other cardiometabolic risk markers. Our findings suggest there may be neutral or possibly detrimental cardiovascular effects of dietary nitrate and/or vitamin C intake which are not in agreement with contemporary literature and warrant further investigation.

The metabolic load-capacity model and cardiometabolic health in children and youth with obesity.

BACKGROUND: The metabolic load-capacity index (LCI), which represents the ratio of adipose to skeletal muscle tissue-containing compartments, is potentially associated with cardiometabolic diseases. OBJECTIVES: To examine the associations between the LCI and cardiometabolic risk factors in children and youth with obesity. METHODS: This is a cross-sectional study including 10-18 years-old participants with a BMI of ≥95th . LCI by air-displacement plethysmography (ADP) was calculated as fat mass divided by fat-free mass, and LCI by ultrasound (US) as subcutaneous adipose tissue divided by skeletal muscle thickness. Sex-specific medians stratified participants into high versus low LCI. Single (inflammation, insulin resistance, dyslipidemia and hypertension) and clustered cardiometabolic risk factors were evaluated. Linear and logistic regression models tested the associations between these variables, adjusted for sexual maturation. RESULTS: Thirty-nine participants (43.6% males; 59% mid-late puberty) aged 12.5 (IQR: 11.1-13.5) years were included. LCI by ADP was positively associated with markers of inflammation and dyslipidemia; having a higher LCI predicted dyslipidemia in logistic regression. Similarly, LCI by US was positively associated with markers of dyslipidemia and blood pressure. In mid-late pubertal participants, LCI by US was positively associated with markers of insulin resistance and inflammation. CONCLUSIONS: Participants with unfavourable cardiometabolic profile had higher LCI, suggesting its potential use for predicting and monitoring cardiometabolic health in clinical settings.

Associations between Aging and Vitamin D Status with Whole-Body Nitric Oxide Production and Markers of Endothelial Function.

BACKGROUND: Aging and vitamin D deficiency have been associated with reduced nitric oxide (NO) synthesis and impaired endothelial function (EF) but the evidence in humans remains weak. OBJECTIVES: Two independent cross-sectional studies were designed to evaluate the association between age, sex, and plasma vitamin D concentrations with physiological and biochemical biomarkers of NO synthesis and EF in young and older healthy participants (Study 1) and in overweight and obese postmenopausal females (Study 2). METHODS: In Study 1, 40 young (20-49 y) and older (50-75 y) males and females (10 participants per age and sex group) were included. Resting blood pressure and ear-to-finger peripheral pulse wave velocity (PWV) were measured. A stable-isotopic method was used to determine whole-body NO production. Plasma 25-hydroxyvitamin D (25(OH)D), nitrate, nitrite, and asymmetric dimethylarginine (ADMA) concentrations were determined. In Study 2, 80 older overweight and obese females (age 61.2 ± 6.2 y, body mass index 29.5 ± 4.4 kg/m2) were recruited. Postocclusion reactive hyperemia (PORH) and peripheral PWV were measured. Plasma concentrations of 25(OH)D, nitrate, cyclic guanosine monophosphate, 3-nitrotyrosine (3-NT), endothelin-1, vascular endothelial growth factor, and ADMA were determined. RESULTS: In Study 1, whole-body NO production was significantly greater in young compared with older participants (0.61 ± 0.30 µmol·h-1·kg-1 compared with 0.39 ± 0.10 µmol·h-1·kg-1, P = 0.01) but there was no evidence of a sex difference (P = 0.81). Plasma 25(OH)D concentration was not associated with PWV (r = 0.18, P = 0.28) or whole-body NO production (r = -0.20, P = 0.22). Plasma ADMA concentration was associated positively with age (r = 0.35, P = 0.03) and negatively with whole-body NO production (r = -0.33, P = 0.04). In Study 2, age was associated with lower PORH (r = -0.28, P = 0.02) and greater ADMA concentrations (r = 0.22, P = 0.04). Plasma 25(OH)D concentration was inversely associated with 3-NT concentrations (r = -0.31, P = 0.004). CONCLUSIONS: Older age was associated with lower whole-body NO production. Plasma vitamin D concentrations were not associated with NO production or markers of EF but showed a weak, significant correlation with oxidative stress in postmenopausal overweight females.

Carrot intake is consistently negatively associated with cancer incidence: A systematic review and meta-analysis of prospective observational studies.

Carrots are main dietary sources of several potential anti-cancer compounds, including polyacetylenes, while ß-carotene has shown no benefits in controlled cancer trials. Accordingly, associations between carrot intake and cancer incidence were quantified, where necessary using α-carotene as a non-causal biomarker of carrot consumption, by searching for studies published before June 2022 reporting risk estimates for relationships of cancer incidence with carrot intake or α-carotene intake or α-carotene plasma concentration, supplemented with hand searches of included studies and reviews. Meta-analyses comparing highest and lowest reported intakes in prospective studies using a random-effects model estimated summary relative risks (RRs) with 95% confidence intervals (CIs), separately for carrot intake or α-carotene plasma concentration, and the corresponding dose-responses. Of 198 observational studies, in 50 prospective studies with 52000 cases recording carrot intake, the cancer-risk was substantially reduced (RR 0.90, 95% CI 0.87-0.94, p ˂ 0·00004). In 30 prospective studies with 9331 cases reporting plasma α-carotene levels, summary RR was 0.80 (0.72-0.89, p ˂ 0·00006). For both exposure types, inter-study heterogeneity was moderate, interaction with cancer types insignificant, and the dose-response significant (p ˂ 0·01). In conclusion, carrot consumption is robustly associated with decreased cancer-risk; carrot consumption should be encouraged, and the causal mechanisms further investigated.

Effects of dietary nitrate and vitamin C co-ingestion on blood pressure and hand-grip strength in young adults.

Background: Co-administration of vitamin C and inorganic nitrate ([Formula: see text]) may reduce oxidative stress, boost the conversion of nitrite ([Formula: see text]) into NO and elicit positive vascular effects. Aims: We aimed to test the effects of oral inorganic [Formula: see text] and vitamin C co-supplementation on vascular function, muscular strength, and on concentrations of urinary [Formula: see text], vitamin C, 8-isoprostanes and salivary [Formula: see text] in healthy young adults. Methods: Ten young healthy participants were enrolled in a randomised, double-blind (only for the [Formula: see text] intervention) crossover clinical trial. Participants consumed in random order: 1) nitrate-rich beetroot juice and vitamin C (N+VC), 2) nitrate-rich beetroot juice alone (N) or 3) nitrate-depleted beetroot juice alone (ND). Resting blood pressure (BP) was measured at the research centre and at home. Non-invasive, continuous measurements of BP and cardiac function parameters were performed using a Finometer device. Free-living physical activity and hand-grip strength were assessed. Salivary [Formula: see text] and [Formula: see text] and urinary [Formula: see text], 8-isoprostanes and vitamin C concentrations were measured. Results: There were no significant differences for any of the vascular outcomes between the three interventions groups. However, analyses of within-intervention changes showed a significant lower daily systolic BP in the [Formula: see text]+vitamin C (N+VC) group only (P=0.04). Urinary [Formula: see text] (P=0.002) and salivary [Formula: see text] (P=0.001) were significantly higher in the N+VC group compared to the N and ND groups. Conclusion: These preliminary findings suggest that combining dietary [Formula: see text] with vitamin C could have protective effects on vascular function in young adults and could represent an effective strategy for the maintenance of healthy cardiovascular trajectories.

Does dietary nitrate boost the effects of caloric restriction on brain health? Potential physiological mechanisms and implications for future research.

Dementia is a highly prevalent and costly disease characterised by deterioration of cognitive and physical capacity due to changes in brain function and structure. Given the absence of effective treatment options for dementia, dietary and other lifestyle approaches have been advocated as potential strategies to reduce the burden of this condition. Maintaining an optimal nutritional status is vital for the preservation of brain function and structure. Several studies have recognised the significant role of nutritional factors to protect and enhance metabolic, cerebrovascular, and neurocognitive functions. Caloric restriction (CR) positively impacts on brain function via a modulation of mitochondrial efficiency, endothelial function, neuro-inflammatory, antioxidant and autophagy responses. Dietary nitrate, which serves as a substrate for the ubiquitous gasotransmitter nitric oxide (NO), has been identified as a promising nutritional intervention that could have an important role in improving vascular and metabolic brain regulation by affecting oxidative metabolism, ROS production, and endothelial and neuronal integrity. Only one study has recently tested the combined effects of both interventions and showed preliminary, positive outcomes cognitive function. This paper explores the potential synergistic effects of a nutritional strategy based on the co-administration of CR and a high-nitrate diet as a potential and more effective (than either intervention alone) strategy to protect brain health and reduce dementia risk.

Vitamin C supplementation showed greater effects on systolic blood pressure in hypertensive and diabetic patients: an updated systematic review and meta-analysis of randomised clinical trials.

Results from randomised controlled trials (RCTs) testing the effect of vitamin C supplementation on blood pressure (BP) have been inconsistent. This systematic review evaluated the effects of vitamin C supplementation on BP and included RCTs testing the effects of vitamin C supplementation alone, on systolic and diastolic BP in adult participants (≥18 years). Random-effect models were conducted to estimate the pooled effects of vitamin C supplementation on BP. A total of 20 studies with 890 participants were included. The median dose of vitamin C was 757.5 mg/d, the median duration was 6 weeks. Vitamin C supplementation was found to reduce systolic BP by -3.0 mmHg (95%CI: -4.7, -1.3 mmHg; p = 0.001). Subgroup analysis showed a more pronounced effect on systolic BP in patients with hypertension (-3.2 mmHg, 95%CI -5.2, -1.2 mmHg, p = 0.002) and diabetes (-4.6 mmHg, 95%CI -8.9, -0.3 mmHg, p = 0.03). Further research needs to evaluate the long-term effect of vitamin C on BP in populations with impaired cardio-metabolic health.