The Department of Clinical Sciences and Nutrition has an experienced team of researchers, with an international reputation. Their main research themes are Public Health Nutrition and Physical Activity, Cardiometabolic Health, and Clinical Practice.

Recent Submissions

  • The Efficacy of Energy-Restricted Diets in Achieving Preoperative Weight Loss for bariatric Pateints: A Systematic Review

    Naseer, Fathimath; Shabbir, Asim; Livingstone, Barbara; Price, Ruth; Syn, Nicholas, L; Flannery, Orla; Ulster University; National University Hospital, Singapore; University of Chester (Springer Verlag, 2018-08-18)
    In bariatric practice, a preoperative weight loss of at least 5% is recommended. However, the hypocaloric diets prescribed vary and no consensus exists. This study examined the efficacy of preoperative diets in achieving 5% weight loss. From a systematic literature search, eight randomised controlled trials (n = 862) were identified. Half of the trials used a Bvery-low-calorie diet^ whilst the rest employed a Blow-calorie diet^. Only five diets achieved ≥ 5% weight loss over varying durations and energy intakes. By inference, compliance with a 700–1050 kcal (2929–4393 kJ) diet, consisting of moderate carbohydrate, high protein and low/moderate fat, for 3 weeks is likely to achieve 5% weight loss. A low-carbohydrate diet (< 20 g/day) may achieve this target within a shorter duration. Additional research is required to validate these conclusions.
  • A universally calibrated microplate ferric reducing antioxidant power (FRAP) assay for foods and applications to Manuka honey

    Bolanos de la Torre, Angelica AS; Henderson, Terence; Nigam, Poonam Singh; Owusu-Apenten, Richard K; Ulster University (Elsevier, 2014-11-07)
    The ferric reducing antioxidant power (FRAP) assay was recently adapted to a microplate format. However, microplate-based FRAP (mFRAP) assays are affected by sample volume and composition. This work describes a calibration process for mFRAP assays which yields data free of volume effects. From the results, the molar absorptivity (ε) for the mFRAP assay was 141,698 M−1 cm−1 for gallic acid, 49,328 M−1 cm−1 for ascorbic acid, and 21,606 M−1 cm−1 for ammonium ferrous sulphate. The significance of ε (M−1 cm−1) is discussed in relation to mFRAP assay sensitivity, minimum detectable concentration, and the dimensionless FRAP-value. Gallic acid showed 6.6 mol of Fe2+ equivalents compared to 2.3 mol of Fe+2 equivalents for ascorbic acid. Application of the mFRAP assay to Manuka honey samples (rated 5+, 10+, 15+, and 18+ Unique Manuka Factor; UMF) showed that FRAP values (0.54–0.76 mmol Fe2+ per 100 g honey) were strongly correlated with UMF ratings (R2 = 0.977) and total phenols content (R2 = 0.982)whilst the UMF rating was correlated with the total phenols (R2 = 0.999). In conclusion, mFRAP assay results were successfully standardised to yield data corresponding to 1-cm spectrophotometer which is useful for quality assurance purposes. The antioxidant capacity of Manuka honey was found to be directly related to the UMF rating
  • Regulation of Inducible Nitric Oxide Synthase by Arabinoxylans with molecular characterization from Wheat Flour in Cultured Human Monocytes

    Zhengxiao, Zhang; Christopher, Smith; Jason, Ashworth; Weili, Li; Manchester Metropolitan University; University of Chester (Wiley, 2018-01-08)
    The immunomodulatory activity of the arabinoxylans (AXs) extracts from cereal sources has been reported to impart health benefits in terms of immune enhancement. This study investigated the effect of enzymatic extraction on extraction yield and structure of AXs from wheat flour pentosan fraction. Under the optimised conditions, the extraction yield of AXs reached up to 81.25%. Furthermore, the study determined whether water-extracted AXs (WEAXs) and enzyme-extracted AXs (E-WEAXs) from wheat flour were able to differentially stimulate nitric oxide (NO) secretion through increased levels of inducible nitric oxide synthase (iNOS) in human U937 monocytes. The results indicated that AXs concomitantly induced (P < 0.05) both NO and iNOS productions in U937 monocytes compared to untreated cells. Compared with WEAXs, E-WEAXs resulted in a higher proportion of low Mw (1–10 KDa) AXs (49.51% vs. 19.11% in WEAXs), a higher A/X ratio (0.83 vs. 0.48 in WEAXs) and a higher yield (12.83 ± 0.35% vs. 7.54 ± 0.47% in WEAXs). Moreover, E-WEAXs induced significantly (P < 0.05) greater NO and iNOS production per million viable cells (61.8 ± 2.7 μm and 42.41 ± 3.83 ng respectively) than WEAXs (51.6 ± 2.6 μm and 33.46 ± 1.48 ng, respectively). The findings suggest AXs may heighten innate immune activity in the absence of infection or disease through an iNOS-mediated stimulation of NO production. The immunomodulatory activity of the wheat-derived AXs was enhanced by enzyme treatment, with low Mw and high A/X ratio associated with elevated NO/iNOS levels in human monocytes compared to water extraction.
  • Improving the extractability of arabinoxylans and the molecular weight of wheat endosperm using extrusion processing

    Abdulmannan, Fadel; Jason, Ashworth; Andrew, Plunkett; Ayman M., Mahmoud; Yazan, Ranneh; University of Leeds; Manchester Metropolitan University; Beni-Suef University; Universiti Putra Malaysia; University of Chester (Elsevier, 2018)
    Cereal derived arabinoxylans (AXs) are non-starch polysaccharides that have immunomodulatory activities. These activities are thought to be related to the low molecular weight fractions of AXs. Wheat and wheat by-products are rich in AXs, however, the water extractable fraction of AXs in wheat products is low. Water extraction of AXs can be improved by extrusion processing, which increases the extractability of the water soluble fraction. The aim of this study was to determine the extractability and molecular weight of the water soluble fraction of AXs from wheat endosperm after extrusion at screw speeds of 80 and 160 rpm. Extrusion processing significantly (P<0.05) increased the water extractability of AXs in a screw-speed dependent manner (13.07±0.12% at 80 rpm and 15.45±0.16% at 160 rpm compared to8.95±0.10% in the non-extruded control) due to a significant increase (P<0.05) in low molecular weight fractions of AXs in extruded samples.
  • Release of coumarin encapsulated in chitosan-gelatin irradiated films

    Benbettaïeb, Nasreddine; Chambin, Odile; Assifaoui, Ali; Al-Assaf, Saphwan; Karbowiak, Thomas; Debeaufort, Frédéric; Phillips Hydrocolloids Research Centre, Glyndwr University, Wrexham LL11 2AW, UK (Elsevier, 2015-12-24)
    Chitosan and fish gelatin were used to formulate active biobased films containing an antioxidant (coumarin). After drying, the films were irradiated at 40 and 60 kGy using an electron beam accelerator. The effect of irradiation on the film properties as well as the coumarin release mechanism were investigated and compared with the control. Electron Spin Resonance (ESR) revealed free radical formation during irradiation in films containing coumarin. Antioxidant addition and/or irradiation treatment at a dose of 60 kGy resulted in a shift of amide A and amide B peaks. Furthermore a shift of amide II band was only observed for the control film at the same dose. Irradiation allowed improving the thermal stability of the control films. Both irradiation process and addition of coumarin increased the surface wettability (increase of the polar component of the surface tension). From the water barrier analysis, neither irradiation nor coumarin addition influenced the permeability at the lower RH gradient used (0e30% RH). Using the higher RH gradient (30e84%) induced a rise of the WVP of all films (containing or not coumarin) after irradiation treatment. At 60 kGy, the tensile strength of only the control films increased significantly. Considering coumarin release from the film in aqueous medium, the apparent diffusion coefficient of coumarin is two times reduced after irradiation. Irradiation also allowed to better protect the incorporated antioxidant. Indeed, the amount of coumarin in the non-irradiated film was significantly lowered compared to the initial quantity, which is probably due to chemical reactivity.
  • Antioxidant and genoprotective activity of selected cucurbitaceae seed extracts and LC–ESIMS/MS identification of phenolic components

    Yasir, Muhammad; Sultana, Bushra; Nigam, Poonam Singh; Owusu-Apenten, Richard; University of Agriculture, Faisalabad, Pakistan; University of California; Ulster University (Elsevier, 2015-11-30)
    Cucurbitaceae are one of most widely used plant species for human food but lesser known members have not been examined for bioactive components. The purpose of this study was to evaluate the antioxidant and genoprotective activities from three cucurbitaceae seeds extracts and to identify phenolic components by LC–ESIMS/MS analysis. From the results, the yield of seeds extract was 20–41% (w/w) and samples had 16–40% total phenols as gallic acid equivalents (GAE). Compared with methanol solvent, using acidified methanol led to increased extraction yield by 1.4 to 10-fold, higher phenolic content (149.5 ± 1.2 to 396.4 ± 1.9 mg GAE/g), higher DPPH radical quenching and enhanced enoprotective activity using the pBR322 plasmid assay. LC–ESI-MS/MS analysis led to identification of 14–17 components, based on authentic standards and comparison with literature reports, as mainly phenolic acids and esters, flavonol glycosides. This may be the first mass spectrometric profiling of polyphenol components from cucurbitaceae seeds.
  • Total Phenols, Antioxidant Capacity and Antibacterial Activity of Manuka Honey Extract.

    Chau, Tsz Ching; Owusu-Apenten, Richard; Nigam, Poonam; Ulster University; University of Chester; (Science Domain International, 2017-10-28)
    Aims: To evaluate total phenols content (TPC), antioxidant capacity (TAC) and antibacterial activity of Manuka honey extract (MHE) and to compare such properties with those for unfractionated Manuka honey. Study Design: In vitro study. Place and Duration of Study: School of Biomedical Sciences, Ulster University, Coleraine, UK. Between September 2016 and September 2017. Methodology: MHE was prepared by solvent extraction using ethyl acetate. TPC was determined by Folin-Ciocalteu assay. The iron (III) reducing antioxidant capacity (IRAC) method was used to determine TAC. Antibacterial activity was evaluated using disc diffusion assay and 96-well microtiter plate methods with absorbance measured at 600 nm. Results: The TPC for MHE was 30-fold higher than the value for Manuka honey (33420±1685 mg vs. 1018±78 mg GAE/kg) while TAC values were~ 100-times greater (83,198±7064 vs. 793±104 TEAC, respectively). Antibacterial activity assessed by disc diffusion for Manuka honey (18.5 mm on S. aureus and 20 mm on E. coli) was two times greater than for MHE (9mm for both S. aureus and E. coli). The 96-well microtiter plate assay confirmed the greater antibacterial activity for Manuka
  • A universally calibrated microplate ferric reducing antioxidant power (FRAP) assay for foods and applications to Manuka honey

    Bolanos de la Torre, Angelica AS; Henderson, Terence; Nigam, Poonam Singh; Owusu-Apenten, Richard K; ONIRIS, Ecole Nationale Vétérinaire; Ulster University; University of Chester; (Elsevier, 2014-11-07)
    The ferric reducing antioxidant power (FRAP) assay was recently adapted to a microplate format. However, microplate-based FRAP (mFRAP) assays are affected by sample volume and composition. This work describes a calibration process for mFRAP assays which yields data free of volume effects. From the results, the molar absorptivity (ε) for the mFRAP assay was 141,698 M−1 cm−1 for gallic acid, 49,328 M−1 cm−1 for ascorbic acid, and 21,606 M−1 cm−1 for ammonium ferrous sulphate. The significance of ε (M−1 cm−1) is discussed in relation to mFRAP assay sensitivity, minimum detectable concentration, and the dimensionless FRAP-value. Gallic acid showed 6.6 mol of Fe2+ equivalents compared to 2.3 mol of Fe+2 equivalents for ascorbic acid. Application of the mFRAP assay to Manuka honey samples (rated 5+, 10+, 15+, and 18+ Unique Manuka Factor; UMF) showed that FRAP values (0.54–0.76 mmol Fe2+ per 100 g honey) were strongly correlated with UMF ratings (R2 = 0.977) and total phenols content (R2 = 0.982)whilst the UMF rating was correlated with the total phenols (R2 = 0.999). In conclusion, mFRAP assay results were successfully standardised to yield data corresponding to 1-cm spectrophotometer which is useful for quality assurance purposes. The antioxidant capacity of Manuka honey was found to be directly related to the UMF rating.
  • Comparison of Iron (III) Reducing Antioxidant Capacity (iRAC) and ABTS Radical Quenching Assays for Estimating Antioxidant Activity of Pomegranate

    Wan, Hau Ching; Sultana, Bushra; Nigam, Poonam Singh; Owusu-Apenten, Richard; University of Ulster; University of Agriculture Parkistan; University of Chester (MDPI, 2018-08-07)
    Pomegranate juice (PJ) has total antioxidant capacity which is reportedly higher compared to other common beverages. This short study aimed to assess the total antioxidant capacity of commercial PJ and pomegranate fruit using a newly described method for iron (III) reducing antioxidant capacity (iRAC) and to compare with the ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) and Folin–Ciocalteu assays. Commercial PJ, freeze-dried pomegranate, and oven-dried pomegranate were analyzed. The calibration results for iRAC were comparable to ABTS and Folin–Ciocalteu methods in terms of linearity (R2 > 0.99), sensitivity and precision. The total antioxidant capacity for PJ expressed as trolox equivalent antioxidant capacity (TEAC) was 33.4 ± 0.5 mM with the iRAC method and 36.3 ± 2.1 mM using the ABTS method. For dried pomegranates, total antioxidant capacity on a dry weight basis (DB) was 89–110 mmol/100 g DB or 76.0 ± 4.3 mmol/100 g DB using iRAC and ABTS methods, respectively. Freeze-dried pomegranate had 15% higher total antioxidant capacity compared with oven-dried pomegranate. In conclusion, pomegranate has high total antioxidant capacity as evaluated by the iRAC and ABTS methods, though variations occur due to the type of cultivar, geographic origin, processing and other factors. The study is relevant for attempts to refine food composition data for pomegranate and other functional foods
  • Visualisation of xanthan conformation by atomic force microscopy

    Moffat, Jonathan; Morris, Victor J.; Al-Assaf, Saphwan; Gunning, A. Patrick; Asylum Research an Oxford Instruments Company; Norwich Research Park; University of Chester (Elsevier, 2016-04-20)
    Direct visual evidence obtained by atomic force microscopy demonstrates that when xanthan is adsorbed from aqueous solution onto the heterogeneously charged substrate mica, its helical conformation is distorted. Following adsorption it requires annealing for several hours to restore its ordered helical state. Once the helix state reforms, the AFM images obtained showed clear resolution of the periodicity with a value of 4.7 nm consistent with the previously predicted models. In addition, the images also reveal evidence that the helix is formed by a double strand, a clarification of an ambiguity of the xanthan ultrastructure that has been outstanding for many years.
  • Effects of temperature and solvent condition on phase separation induced molecular fractionation of gum arabic/hyaluronan aqueous mixtures

    Hu, Bing; Han, Lingyu; Gao, Zhiming; Zhang, Ke; Al-Assaf, Saphwan; Nishinari, Katsuyoshi; Phillips, Glyn O.; Yang, Jixin; Fang, Yapeng; Hubei University of Technology; Wrexham Glyndwr University (Elsevier, 2018-05-14)
    Effects of temperature and solvent condition on phase separation-induced molecular fractionation of gum arabic/hyaluronan (GA/HA) mixed solutions were investigated. Two gum arabic samples (EM10 and STD) with different molecular weights and polydispersity indices were used. Phase diagrams, including cloud and binodal curves, were established by visual observation and GPC-RI methods. The molecular parameters of control and fractionated GA, from upper and bottom phases, were measured by GPC-MALLS. Fractionation of GA increased the content of arabinogalactan-protein complex (AGP) from ca. 11% to 18% in STD/HA system and 28% to 55% in EM10/HA system. The phase separation-induced molecular fractionation was further studied as a function of temperature and solvent condition (varying ionic strength and ethanol content). Increasing salt concentration (from 0.5 to 5 mol/L) greatly reduced the extent of phase separation-induced fractionation. This effect may be ascribed to changes in the degree of ionization and shielding of the acid groups. Increasing temperature (from 4oC to 80oC) also exerted a significant influence on phase separation-induced fractionation. The best temperature for GA/HA mixture system was 40oC while higher temperature negatively affected the fractionation due to denaturation and possibly degradation in mixed solutions. Increasing the ethanol content up to 30% showed almost no effect on the phase separation induced fractionation.
  • Arabinoxylans: Bioactivities in Relation to Their Molecular Structure

    Li, Weili; Zhang, Zhengxiao; Smith, Christopher J.; University of Chester; Manchester Metropolitan University (Bentham Science, 2017-03-09)
    Arabinoxylans are a group of compounds with a basic structure consisting of a xylose backbone with arabinose side chains. Variations in structure occur as a result of variations in the xylose chain length, the ratio of arabinose to xylose and the introduction of alternative side-chains. This allows for an enormous potential range of structures. Arabinoxylans are major components of the cell walls of cereals. They have been reported to have numerous health benefits. This chapter presents a systematic description of the molecular features of arabinoxylans and relates these to the different extraction technologies used to obtain them. The proposal, that their immune modulation activity is related to their molecular weight and structure, is presented. Results demonstrating the effects of various arabinoxylans in various in vitro immunological tests are discussed.
  • Modulation of Innate and Adaptive Immune Responses by Arabinoxylans

    Fadel, Abdulmannan; Plunkett, Andrew; Li, Weili; Ashworth, Jason J.; Manchester Metropolitan University; University of Chester; Al-Baha University; Al-Ahliyya Amman University; Universiti Putra Malaysia; Istanbul Universitesi (Wiley, 2017-11-30)
    Humans are exposed to harmful pathogens and a wide range of noxious substances every day.The immune system reacts to, and destroys, these pathogens and harmful substances. The immunesystem is composed of innate and adaptive immunity, which liaise to protect the host and maintainhealth. Foods, especially cereals, have been reported to modulate the immune response.Arabinoxylans are nonstarch polysaccharides that have been shown to possess immune-modulatory activities. This review article discusses the fundamentals of the immune system andprovides an overview of the immunomodulatory potential of arabinoxylans in conjunction withtheir structural characteristics and proposed similarities with lipopolysaccharides
  • The development of vegetarian omega-3 oil in water nanoemulsions suitable for integration into functional food products

    Lane, Katie E.; Li, Weili; Smith, Christopher J.; Derbyshire, Emma J.; Liverpool John Moores University; University of Chester (Elsevier, 2016-03-31)
    Global trends show that habitual omega-3 intakes are short of recommended guidelines, particularly among vegetarians and vegans. The potential health implications of low long chain omega-3 polyunsaturated fatty acid (LCω3PUFA) intakes coupled with concerns about sustainability of fish stocks call for innovative approaches to provide food based solutions to this problem. Nanoemulsions are systems with extremely small droplet sizes that could provide a solution while improving the bioavailability of LCω3PUFA. Oil in water nanoemulsion systems were successfully created using ultrasound with oil loads of up to 50% (w/w) using vegetarian LCω3PUFA oils (flaxseed and algae). Nanoemulsions of 50% (w/w) with mean droplet size measurements of 192 (flaxseed) and 182 nm (algae) using combinations of the emulsifiers Tween 40 and lecithin were prepared. This technique could be applied to create vegetarian LCω3PUFA nanoemulsions suitable for integration into enriched functional food products with the potential to increase LCω3PUFA intake and bioavailability
  • Health-related effects and improving extractability of cereal arabinoxylans

    Fadel, Abdulmannan; Mahmoud, Ayman M.; Ashworth, Jason J.; Li, Weili; Ng, Yu L.; Plunkett, Andrew; Manchester Metropolitan University; Beni-Suef University; Charité-University Medicine; University of Chester (Elsevier, 2017-11-11)
    Arabinoxylans (AXs) are major dietary fibers. They are composed of backbone chains of -(1–4)- linked xylose residues to which -l-arabinose are linked in the second and/or third carbon positions. Recently, AXs have attracted a great deal of attention because of their biological activities such as their immunomodulatory potential. Extraction of AXs has some difficulties; therefore, various methods have beenusedto increase the extractability ofAXs withvaryingdegrees of success, suchas alkaline, enzymatic, mechanical extraction. However, some of these treatments have been reported to be either expensive, such as enzymatic treatments, or produce hazardous wastes and are non-environmentally friendly, such as alkaline treatments. On the other hand, mechanical assisted extraction, especially extrusion cooking, is an innovative pre-treatment that has been used to increase the solubility of AXs. The aim of the current review article is to point out the health-related effects and to discuss the current research on the extraction methods of AXs.
  • Characterization of Nitric Oxide Modulatory Activities of Alkaline-Extracted and Enzymatic-Modified Arabinoxylans from Corn Bran in Cultured Human Monocytes

    Zhang, Zhengxiao; Smith, Christopher J.; Li, Weili; Ashworth, Jason J.; Manchester Metropolitan University; University of Chester (American Chemical Society, 2016-10-10)
    The ingestion of foods and food-derived substances that may mediate the immune system is widely studied. Evidence suggests cereal arabinoxylans (AXs) have immunomodulatory activities that may impart health benefits in terms of immune enhancement. This study extracted AXs from corn bran using alkali and developed a modification process using three endoxylanases to obtain fractions of lower molecular weight ranges. In vitro studies showed extracted and modified AXs significantly (P < 0.05) elevated nitric oxide (NO) synthesis by the human U937 monocytic cell line (ranging from 53.7 ± 1.1 to 62.9 ± 1.2 μM per million viable cells) at all concentrations tested (5–1000 μg/mL), indicative of immune enhancement compared to an untreated control (43.7 ± 1.9 μM per million viable cells). The study suggested the dose range and Mw distribution of AXs are key determinants of immune-modulatory activity. AXs in the low Mw range (0.1–10 KDa) were the most effective at inducing NO secretion by U937 macrophages at low AX concentration ranges (5–50 μg/mL), with NO production peaking at 62.9 ± 1.2 μM per million viable cells with 5 μg/mL of AX (P = 0.0009). In contrast, AXs in the high Mw range (100–794 kDa) were most effective at inducing NO at high AX concentration ranges (500–1000 μg/mL) with NO production reaching a maximum of 62.7 ± 1.3 μM per million viable cells at 1000 μg/mL of AX (P = 0.0011). The findings suggest that dietary AXs from corn bran may heighten innate immune responses in the absence of infection or disease.
  • Regulation of Nitric Oxide Synthase Expression by Structure Modified Arabinoxylans from Wheat Flour in Cultured Human Monocytes

    Zhang, Zhengxiao; Smith, Christopher J.; Ashworth, Jason J.; Li, Weili; Manchester Metropolitan University; University of Chester (Wiley, 2018-01-08)
    The immunomodulatory activity of the arabinoxylans (AXs) extracts from cereal sources has been reported to impart health benefits in terms of immune enhancement. This study investigated the effect of enzymatic extraction on extraction yield and structure of AXs from wheat flour pentosan fraction. Under the optimised conditions, the extraction yield of AXs reached up to 81.25%. Furthermore, the study determined whether water-extracted AXs (WEAXs) and enzyme-extracted AXs (E-WEAXs) from wheat flour were able to differentially stimulate nitric oxide (NO) secretion through increased levels of inducible nitric oxide synthase (iNOS) in human U937 monocytes. The results indicated that AXs concomitantly induced (P < 0.05) both NO and iNOS productions in U937 monocytes compared to untreated cells. Compared with WEAXs, E-WEAXs resulted in a higher proportion of low Mw (1–10 KDa) AXs (49.51% vs. 19.11% in WEAXs), a higher A/X ratio (0.83 vs. 0.48 in WEAXs) and a higher yield (12.83 ± 0.35% vs. 7.54 ± 0.47% in WEAXs). Moreover, E-WEAXs induced significantly (P < 0.05) greater NO and iNOS production per million viable cells (61.8 ± 2.7 μm and 42.41 ± 3.83 ng respectively) than WEAXs (51.6 ± 2.6 μm and 33.46 ± 1.48 ng, respectively). The findings suggest AXs may heighten innate immune activity in the absence of infection or disease through an iNOS-mediated stimulation of NO production. The immunomodulatory activity of the wheat-derived AXs was enhanced by enzyme treatment, with low Mw and high A/X ratio associated with elevated NO/iNOS levels in human monocytes compared to water extraction.
  • A 1-h time interval between a meal containing iron and consumption of tea attenuates the inhibitory effects on iron absorption: a controlled trial in a cohort of healthy UK women using a stable iron isotope.

    Ahmad Fuzi, Salma F.; Koller, Dagmar; Brugrabber, Sylvaine; Pereira, Dora I. A.; Dainty, Jack R.; Mushtaq, Sohail; University of Chester; Elsie Widdowson Laboratory, Cambridge; University of East Anglia; University Putra Malaysia (American Society for Nutrition, 2017-10-18)
    Background: Tea has been shown to be a potent inhibitor of nonheme iron absorption, but it remains unclear whether the timing of tea consumption relative to a meal influences iron bioavailability. Objective: The aim of the study was to investigate the effect of a 1-h time interval of tea consumption on nonheme iron absorption in an iron-containing meal in a cohort of iron-replete, nonanemic female subjects with the use of a stable isotope (57Fe). Design: Twelve women (mean 6 SD age: 24.8 6 6.9 y) were administered a standardized porridge meal extrinsically labeled with 4 mg 57Fe as FeSO4 on 3 separate occasions, with a 14-d time interval between each test meal (TM). The TM was administered with water (TM-1), with tea administered simultaneously (TM-2), and with tea administered 1 h postmeal (TM-3). Fasted venous blood samples were collected for iron isotopic analysis and measurement of iron status biomarkers. Fractional iron absorption was estimated by the erythrocyte iron incorporation method. Results: Iron absorption was 5.7% 6 8.5% (TM-1), 3.6% 6 4.2% (TM-2), and 5.7% 6 5.4% (TM-3). Mean fractional iron absorption was found to be significantly higher (2.2%) when tea was administered 1 h postmeal (TM-3) than when tea was administered simultaneously with the meal (TM-2) (P = 0.046). An w50% reduction in the inhibitory effect of tea (relative to water) was observed, from 37.2% (TM-2) to 18.1% (TM-3). Conclusions: This study shows that tea consumed simultaneously with an iron-containing porridge meal leads to decreased nonheme iron absorption and that a 1-h time interval between a meal and tea consumption attenuates the inhibitory effect, resulting in increased nonheme iron absorption. These findings are not only important in relation to the management of iron deficiency but should also inform dietary advice, especially that given to those at risk of deficiency. This trial was registered at clinicaltrials.gov as NCT02365103.
  • Impact of vitamin D supplementation on endothelial and inflammatory markers in adults: A systematic review.

    Agbalalah, Tari; Hughes, Stephen F.; Freeborn, Ellen J.; Mushtaq, Sohail; University of Chester (Elsevier, 2017-01-23)
    This systematic review aims to evaluate randomised controlled trials (RCTs) investigating the effect of vitamin D supplementation on endothelial function and inflammation in adults. An electronic search of published randomised controlled trials, using Cochrane, Pubmed and Medline databases was conducted, with the search terms related to vitamin D and endothelial function. Inclusion criteria were RCTs in adult humans with a measure of vitamin D status using serum/plasma 25(OH)D and studies which administered the intervention through the oral route. Among the 1107 studies retrieved, 29 studies met the full inclusion criteria for this systematic review. Overall, 8 studies reported significant improvements in the endothelial/inflammatory biomarkers/parameters measured. However, in 2 out of the 8 studies, improvements were reported at interim time points, but improvements were absent post-intervention. The remaining 21 trial studies did not show significant improvements in the markers of interest measured. Evidence from the studies included in this systematic review did not demonstrate that vitamin D supplementation in adults, results in an improvement in circulating inflammatory and endothelial function biomarkers/parameters. This systematic review does not therefore support the use of vitamin D supplementation as a therapeutic or preventative measure for CVD in this respect.
  • Optimising the management of bone disease for coeliac patients in a dietetic-led clinic

    Martin, Kirsty J.; Woodall, Alison; University Hospital Aintree and The Walton Centre NHS Foundation Trust; University of Chester (Science and Education Publishing Co., 2016-06)
    Coeliac disease (CD) is a chronic autoimmune inflammatory condition of the small bowel; the only treatment is lifelong adherence to a gluten free diet (GFD). Adherence to a GFD also minimises the risk of associated conditions such as osteoporosis in CD patients. The present study aimed to evaluate and optimise management of bone disease in CD patients in a dietetic-led clinic. This study was conducted in two parts: study 1 utilised retrospective data to evaluate management of bone disease with reference to British Society of Gastroenterology (BSG) guidelines in 229 CD patients. Based on the results from study 1, study 2 developed a tool to estimate dietary calcium intake in CD patients, which was then trialled on 50 patients. There were no significant differences between the population demographics for study 1 and study 2. 65% of patients had a diagnosis of osteopenia or osteoporosis, in a female predominant population (74.6%). Reported mean dietary calcium intake was over estimated at 1239.6mg/day (SD ± 377.1mg) in study 1 and corrected to 852mg/day (SD ± 264.57mg) using improved methodology (study 2) (p≤0.05). Understanding and compliance with dietary advice correlated positively with GFD (p≤0.001) but not osteoporosis or fracture risk. Overall patients attending the clinic did not meet the BSG recommended calcium intake. However, 30% of patients could meet the 2014 BSG target from oral diet alone. Utilising individual dietary prescriptions and targeted use of calcium supplementation maximised the opportunity to reduce risk of bone disease and improved compliance with BSG recommendations.

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