Browsing by Author "Von Hurst PR"

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    Evaluation of protein intake and protein quality in New Zealand vegans
    (PLOS, 2025-04-16) Soh BXP; Vignes M; Smith NW; Von Hurst PR; McNabb WC; Tomaszewska E
    Dietary protein provides indispensable amino acids (IAAs) that the body cannot synthesise. Past assessments of total protein intake from vegan populations in western, developed countries were found to be low but not necessarily below daily requirements. However, plant-sourced proteins generally have lower quantities of digestible IAAs as compared to animal-sourced proteins. Simply accounting for protein intake without considering AA profile and digestibility could overestimate protein adequacy among vegans. This study quantified protein intake and quality, as compared to reference intake values among 193 NZ vegans using a four-day food diary. Protein and IAA composition of all foods were derived from New Zealand FoodFiles and the United States Department of Agriculture and adjusted for True Ileal Digestibility (TID). Mean protein intakes for males and females were 0.98 and 0.80g/kg/day, respectively with 78.8% of males and 73.0% of females meeting the Estimated Average Requirement for protein. Plant-sourced proteins provided 52.9mg of leucine and 35.7mg of lysine per gram of protein and were below the reference scoring patterns (leucine: 59mg/g, lysine: 45mg/g). When adjusted to individual body weight, average IAA intakes were above daily requirements, but lysine just met requirements at 31.0mg/kg of body weight/day (reference: 30mg/kg/day). Upon TID adjustment, the percentage of vegans meeting adequacy for protein and IAA decreased and only approximately 50% of the cohort could meet lysine and leucine requirements. Hence, lysine and leucine were the most limiting IAAs in the vegan cohort’s diet. Legumes and pulses contributed most to overall protein and lysine intake. An increased proportion of legumes and pulses can potentially increase these intakes but must be considered in the context of the whole diet. AA composition and digestibility are important aspects of protein quality when assessing protein adequacy and is of particular importance in restrictive diets.
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    Hypoglycemic effects of antioxidant-rich plant extracts on postprandial glycemic responses in participants with prediabetes (GLARE study)
    (Food Science Publisher on behalf of the Academic Society for Functional Foods and Bioactive Compounds (ASFFBC), 15/11/2021) Lim WXJ; Gammon CS; Von Hurst PR; Chepulis L; Mugridge O; Page RA
    Background: Plant extracts may help to improve glycemic control in individuals with poor glycemic control. However, few studies have been investigated in the prediabetes cohort, which is a high-risk condition for T2DM. Thus, this study aimed to investigate the acute effect of grape seed, rooibos tea, and olive leaf extracts on postprandial blood glucose and insulin in participants with prediabetes. Methods: An acute, single-blind, placebo-controlled, non-randomized, crossover study (ACTRN12617000837325) where placebo and extracts of grape seed, rooibos tea and olive leaf standardized for total antioxidant capacity were given separately during an oral glucose tolerance test to participants (n=19, five men and fourteen women, aged 65.0 ± 1.6 years, Body Mass Index (BMI) 27.3 ± 1.1 kg/m2) with prediabetes (Glycated hemoglobin A1c (HbA1c) 42 ± 1 mmol/mol). The primary outcome incremental area under the curve of glucose (iAUCglucose) was examined with other glycemic measures. Data was analyzed using linear mixed model for repeated measures. Secondary analysis was conducted by stratifying participants into either a healthier or less healthy subgroup based on the postprandial time to glucose and insulin peaks, with the less healthy subgroup experiencing delayed glucose and/or insulin peaks. Results: There were no overall significant changes to glucose and insulin measures between all plant extracts and placebo (p>0.05). Upon secondary analysis, all extracts affected glycemic responses in the less healthy subgroup. Compared to placebo, grape seed reduced plasma iAUCglucose (p=0.016, 21.9% reduction), 2 h postprandial glucose (2hPG) (p=0.034, 14.7% reduction) and metabolic clearance rate of glucose (MCRglucose) (p=0.016, 16.7% increase). It also improved insulin indices such as 2 h postprandial insulin (2hPI) (p=0.029, 22.4% reduction) and Stumvoll overall insulin sensitivity index (ISIoverall) (p=0.028, 15.0% increase). Rooibos tea extract significantly improved β-cell function as demonstrated by the increased oral disposition index (DI) (p=0.031, 32.4% increase) compared to placebo. Olive leaf extract significantly increased incremental area under the curve of insulin (iAUCinsulin) (p=0.040, 16.7% increase). Conclusion: Grape seed, rooibos tea and olive leaf extracts demonstrated acute hypoglycemic benefits in adults with prediabetes and having less healthy metabolic profiles. A chronic study on the plant extracts is warranted to determine their longer-term impact on prediabetes. Trial Registration ID: ACTRN12617000837325
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    Plasma nervonic acid levels were negatively associated with attention levels in community-living older adults in New Zealand
    (Springer Nature, 2022-08) de Seymour JV; Beck KL; Conlon CA; Von Hurst PR; Mumme KD; Haskell-Ramsay CF; Jones MB
    The global population is aging. Preserving function and independence of our aging population is paramount. A key component to maintaining independence is the preservation of cognitive function. Metabolomics can be used to identify biomarkers of cognition before noticeable deterioration. Our study investigated the plasma metabolome of 332 community-living New Zealanders between 65 and 74 years of age, using gas chromatography-mass spectrometry. Six cognitive domains were assessed. Of the 123 metabolites identified using an in-house mass spectral libraries of standards, nervonic acid had a significant, inverse association with the attention domain (P-value = 1.52E− 4; FDR = 0.019), after adjusting for covariates (apolipoprotein E -ε4 genotype, sex, body fat percentage (standardised by sex), age, education, deprivation index, physical activity, metabolic syndrome, polypharmacy, smoking status, and alcohol intake) and multiple testing. Attention is defined as the ability to concentrate on selected aspects of the environment while ignoring other stimuli. This is the first study to identify nervonic acid as a potential biomarker of attention in older adults. Future research should confirm this association in a longitudinal study.
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    Protein intake, distribution, and sources in community-dwelling older adults living in Auckland, New Zealand
    (IOS Press, 2023-10-13) Hiol AN; Von Hurst PR; Conlon CA; Mumme KD; Beck KL
    BACKGROUND: To maximally stimulate muscle protein synthesis (MPS), older adults should consume≥1.2 g/kg body weight (BW) of high-quality protein, evenly distributed across the day ( 0.4 g/kg BW per meal). OBJECTIVES: To investigate protein intake, distribution, and sources in community-dwelling older adults. METHODS: Data (including a 4-day food record) were obtained from the Researching Eating, Activity, and Cognitive Health (REACH) study, a cross-sectional study in adults aged 65 to 74 years. RESULTS: Participants (n = 327, 65.4% female) had a median daily protein intake of 1.16 g/kg BW (males) and 1.09 g/kg BW (females). Over half of participants consumed less than 1.2 g protein/kg BW/day (62% females, 57% males). Protein intake was unevenly distributed throughout the day (CV = 0.48 for males and females) and was inadequate for reaching 0.4 g/kg BW/meal at breakfast and at the mid-day meal (males only). The main sources of protein at breakfast were milk (28%), breakfast cereals (22%), and bread (12%); at the mid-day meal, bread (18%), cheese (10%) and milk (9%); and at the evening meal, meat provided over half the protein (56%). CONCLUSIONS: Protein intake for a high proportion of older adults was less than 1.2 g/kg BW/day, and unevenly distributed through the day. Protein was obtained mainly from cereals and dairy products at breakfast and the mid-day meal, and meat sources at the evening meal.
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    Relationship between vitamin D, iron, and hepcidin in premenopausal females, potentially confounded by ethnicity.
    (Springer Nature, 2023-08-29) Greenwood A; Von Hurst PR; Beck KL; Mazahery H; Lim K; Badenhorst CE
    PURPOSE: To investigate the associations between vitamin D, hepcidin, and iron status in premenopausal females of different ethnic cohorts residing in Auckland, New Zealand (NZ). METHODS: A total of 160 females aged 18-45 years participated in a cross-sectional study. Demographics, body composition, serum 25(OH)D, inflammatory markers (C-reactive protein and interleukin-6, IL-6), and iron biomarkers (serum ferritin, haemoglobin, soluble transferrin receptor, and hepcidin) were measured. Comparisons between parametric, non-parametric, and categorical variables were completed by using one-way ANOVA, Kruskal-Wallis, and Chi-squared tests, respectively. ANCOVA was used to compare serum 25(OH)D across iron parameter categories. RESULTS: Of the 160 participants, 60 were NZ European, 67 were South Asian, and 33 were from the 'other' ethnic groups. South Asians had significantly higher body fat percentage (BF%) and IL-6 concentration (38.34% and 1.66 pg·mL-1, respectively), compared to NZ Europeans (27.49% and 0.63 pg·mL-1, respectively, p < 0.001). South Asians had significantly lower 25(OH)D concentrations compared to NZ Europeans (33.59 nmol·L-1 vs 74.84 nmol·L-1, p < 0.001). In NZ Europeans, higher 25(OH)D concentration was seen in those with lower (≤ 3.5 nM) hepcidin concentration, p = 0.0046. In South Asians, higher 25(OH)D concentration was seen in those with higher (> 3.5 nM) hepcidin concentrations, p = 0.038. There were no associations between serum 25(OH)D and serum ferritin. CONCLUSION: Within South Asian women, an unexpected positive relationship between 25(OH)D and hepcidin concentration was observed which may be due to significantly higher IL-6 concentrations, BF%, and lower 25(OH)D concentrations. Future research is required to confirm these observations in this ethnic cohort.
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    Starting complementary feeding with vegetables only increases vegetable acceptance at 9 months: a randomized controlled trial
    (Oxford University Press on behalf of the American Society for Nutrition, 2022-07-09) Rapson JP; Von Hurst PR; Hetherington MM; Mazahery H; Conlon CA
    BACKGROUND: Starting complementary feeding (CF) with vegetables only may improve vegetable acceptance throughout childhood. OBJECTIVES: We aimed to test whether exposure to vegetables only during the first 4 wk of CF increases later vegetable acceptance compared with a control group receiving fruit and vegetables. METHODS: In this randomized, controlled, parallel-group study, 117 Auckland infants received either vegetables only (veg-only, n = 61) or a combination of fruit and vegetables (control, n = 56) for a duration of 4 wk, starting from the first day of CF at ∼4-6 mo of age. The primary outcome measure was intake of target vegetables (broccoli, spinach) provided by the study at 9 mo of age. Daily intake of vegetables (FFQs) at 9 mo was a supporting measure. Infants' iron status (serum ferritin, hemoglobin) was examined at all time points. RESULTS: The veg-only infants consumed more broccoli and spinach than controls [mean difference (95% CI): 11.83 (0.82, 22.84) g, P = 0.036 and 10.19 (0.50, 19.87) g, P = 0.039, respectively]. Intake of pear was comparable among intervention groups (P = 0.35). At 9 mo, veg-only infants consumed target vegetables at a faster rate [mean difference (95% CI): broccoli, 3.37 (1.26, 5.47), P = 0.002; spinach, 4.12 (0.80, 7.45), P = 0.016] and showed greater acceptance for target vegetables [mean difference (95% CI): broccoli, 0.38 (0.07, 0.70), P = 0.019; spinach, 032 (0.04, 0.60), P = 0.024] than controls. The rate of eating and acceptance of pear was comparable among intervention groups (P = 0.42 and P = 0.98, respectively). Also, veg-only infants consumed more vegetables than controls [86.3 (52.5, 146.3) compared with 67.5 (37.5, 101.3) g, respectively, P = 0.042]. Introducing vegetables as the first food was not associated with 9-mo iron status. CONCLUSIONS: Providing vegetables as first foods increased vegetable intake at 9 mo of age and may be an effective strategy for improving child vegetable consumption and developing preferences for vegetables in infancy.
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    The Effects of GreenShell Mussel Powder (Brand-Named PERNAULTRA) on Physical Performance and Subjective Pain, Symptoms, and Function Measures in Knee Osteoarthritis: A 6-Mo Randomized, Double-Blind, Placebo-Controlled Trial
    (Elsevier Inc. on behalf of American Society for Nutrition, 2024-04) Slade CAJ; Kruger MC; Miller MR; Mazahery H; Beck KL; Conlon CA; Von Hurst PR
    Background: Osteoarthritis (OA) can cause disability and reduce quality of life (QoL). Objectives: This study aimed to determine whether GreenShell mussel (GSM) powder (PERNAULTRA) consumption was more effective than placebo at improving physical performance and subjective measures of symptoms and function in adults with early signs of knee OA. Methods: The Researching Osteoarthritis and GSM study was a 6-mo randomized, double-blind, placebo-controlled trial in adults aged 55–80 y, screened for signs of OA (n = 120, 65.9 ± 6.43 y, 63% female). Participants consumed either 3 g of powdered whole GSM or placebo (pea protein) daily. Baseline and end data collection included 30-s chair stand, stair test, 40-m fast-paced walk test, Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire categorized into 5 subscales [pain (P), symptoms except pain (S), function in activities of daily living (ADL), function in sports/recreation (SP), and QoL], a measure of Intermittent and Constant Osteoarthritis Pain, and visual analog scale of pain and symptoms. Results: Visual analog scale symptoms showed a significantly greater reduction in percentage change for GSM than that for placebo [−28.1 (−59.2, 43.2) compared with 0.00 (−28.6, 100); P = 0.03]. Further, a trend for improvement in percentage change for GSM compared with placebo was seen in 40m fast-paced walk [2.51 (−3.55, 8.12) compared with 0.20 (−6.58, 4.92); P = 0.09], KOOS-SP [11.4 (−4.48, 27.0) compared with 0.00 (−11.1, 17.7); P = 0.09], and Intermittent and Constant Osteoarthritis Pain intermittent pain scale [−27.7 (−77.3, 0.00) compared with −14.6 (−50.0, 36.4); P = 0.08]. In those with body mass index (BMI; in kg/m2) <25, GSM consumption significantly improved KOOS-S compared with placebo [6.35 (3.49, 12.7) compared with 0.00 (−4.65, 4.49); P = 0.03] and showed a trend for improvement in KOOS-ADL [3.29 (1.01, 8.79) compared with 1.01 (−5.75, 4.30); P = 0.07]. Those with BMI of ≥25, consuming GSM showed a trend for improvement in KOOS-SP [13.6 (−4.76, 33.3) compared with 0.00 (−12.5, 20.0); P = 0.07]. Conclusions: This research suggests consumption of GSM has potential to alleviate symptoms and improve functionality in OA. This trial was registered at Clinical Trial Registry as ACTRN12620001112954p (https://www.anzctr.org.au/ACTRN12620001112954p.aspx).