Publicaciones H&NS

Dennis-Wall, J. C., Burns, A. M., Solch, R. J., Ukhanova, M., . . . Langkamp-Henken, B. (2019). A beverage containing orange pomace improves laxation and modulates the microbiome in healthy adults: A randomised, blinded, controlled trial. Journal of Functional Foods, 60. 103438.  doi:10.1016/j.jff.2019.103438

Abstract:

The aim was to assess whether citrus pomace increases stool frequency in healthy adults. In this randomised, blinded, controlled trial, healthy adults (62% females) received a beverage containing pomace (473 mL/day, providing 10 g fibre/day, n = 111) or control (n = 110) for 3 weeks. Stool frequency, Bristol Stool Form Scale (BSFS), and Gastrointestinal Symptom Rating Scale (GSRS) scores were self-assessed. 24-h diet recalls were completed once/week. Stool microbiota were analysed by 16S rRNA sequencing and qPCR. Mean total daily fibre intake was higher with pomace vs. control (P < 0.0001). Mean weekly stool frequency was higher, indicating improved laxation, with pomace vs. control (P = 0.0281) and increased from baseline with pomace (P = 0.0003) but was unchanged with control. Mean BSFS scores were higher with pomace vs. control (P = 0.04). GSRS indigestion syndrome scores, specifically symptoms of gas and bloating, were higher with pomace, suggesting fermentation. Pomace intake increased faecal OTUs corresponding to Lachnospiraceae and Ruminococcaceae.

Wolever, T. M. S., Jenkins, A. L., Yang, J., Nisbet, M., . . . Pan, Y. (2019). An optimized, slowly digested savory cluster reduced postprandial glucose and insulin responses in healthy human subjects. Current Developments in Nutrition, 3(3), nzz006. doi:10.1093/cdn/nzz006

Abstract:

Background: Slowly digested carbohydrates are perceived as beneficial by some consumers, and various regulatory bodies have published specific criteria defining lower postprandial glycemic response. We developed an optimized savory cluster snack containing slowly digested starch. Objective: We compared the glucose and insulin responses elicited by the optimized (test-) cluster, a control-cluster, and an available-carbohydrate-matched portion of white bread in healthy individuals. The primary outcome was blood-glucose peak rise. We tested healthy individuals (n = 25) on 3 occasions using a randomized crossover design. On each occasion, the participants provided fasting blood samples and then consumed 1 serving of test-cluster, control-cluster, or white bread. We then measured the participants’ blood-glucose and serum-insulin concentrations over the next 4 h. Results: The test-cluster elicited a significantly lower blood-glucose peak rise (mean ± SEM: 1.24 ± 0.09 mmol/L) and incremental area under the curve (iAUC; 67 ± 8 mmol × min/L) than the control-cluster (2.27 ± 0.13 mmol/L and 117 ± 10 mmol × min/L, respectively) and white bread (2.27 ± 0.16 mmol/L and 114 ± 9 mmol × min/L, respectively). The serum-insulin peak rise and iAUC elicited by the test-cluster (128 ± 13 pmol/L and 6.10 ± 0.73 nmol × min/L, respectively) and white bread (141 ± 20 pmol/L and 6.47 ± 1.11 nmol × min/L, respectively) were significantly lower than those elicited by the control-cluster (205 ± 26 pmol/L and 9.60 ± 1.31 nmol × min/L, respectively). Conclusion: The test-cluster elicited lower glucose and insulin responses than the control-cluster. The results support the hypothesis that the carbohydrates in the test-cluster are digested and absorbed slowly in vivo.

Young, H. A., Cousins, A., Johnston, S., Fletcher, J. M., & Benton, D. (2019). Autonomic adaptations mediate the effect of hydration on brain functioning and mood: Evidence from two randomized controlled trials. Scientific Reports, 9(1), 16412. doi:10.1038/s41598-019-52775-5

Abstract:

Dehydration (water loss >2.0% of body weight) has significant negative effects on physical and mental performance. In two studies the effects of minor hypo-hydration (water loss <1.0% of body weight) on CNS function, mood and cardiovascular functioning were measured. Study 1: On two mornings twelve male participants were exposed to a temperature of 30 °C for four hours and either did or did not drink two 150 ml glasses of water during that time. Study 2: Fifty-six (25 M) individuals were exposed to the same 30 °C environment and randomly allocated to either drink (2 × 150 ml) or not drink. When not given water 0.59% (Study 1) and 0.55% (Study 2) bodyweight was lost. Participant’s heart rate variability (HRV) was measured, and they rated their thirst and mood. In study 1, participants participated in an fMRI protocol during which they completed a modified version of the Paced Auditory Serial Addition Test (PASAT), at the end of which they rated its difficulty. Decreases in fMRI BOLD activity in the orbito-frontal cortex, ventral cingulate gyrus, dorsal cingulate cortex, hypothalamus, amygdala, right striatum, post-central gyrus and superior parietal cortex were observed when participants were hypo-hydrated. These deactivations were associated with reduced HRV, greater perceived effort, and more anxiety. In study 2 declines in HRV were found to mediate the effect of hypo-hydration on ratings of anxiety. These data are discussed in relation to a model that describes how autonomic regulatory and interoceptive processes may contribute to the affective consequences of minor hypo-hydration.

Ding, J., Johnson, J., Chu, Y. F., & Feng, H. (2019). Enhancement of γ-aminobutyric acid, avenanthramides, and other health-promoting metabolites in germinating oats (avena sativa L.) treated with and without power ultrasound. Food Chemistry, 283, 239-247. doi:10.1016/j.foodchem.2018.12.136

Abstract:

Power ultrasound as an emerging processing technology has been investigated for stimulating seeds to enhance germination and accumulation of health-promoting metabolites, such as γ-aminobutyric acid (GABA) and phenolic compounds. This work was undertaken to evaluate the effects of power ultrasound (25 kHz) on the nutritional properties of germinated oats, and the microstructure of oat groats after treatment. The changes in the external and internal microstructures of the ultrasound-treated oats kernel were investigated using Environmental Scanning Electron Microscopy (ESEM) and 3D X-ray Micro Computed Tomography (Micro-CT). Physicochemical properties of oats including GABA, free sugars, avenanthramides, total phenolic content, and antioxidant capacities were enhanced after germination. Furthermore, the power ultrasound treatment for 5 min after soaking significantly enhanced the GABA (48–96 h), alanine (24–96 h), succinic acid (48–72 h), total phenolic content (24 h), and total avenanthramides (24 h) in the germinated oats.

Huang, Y., Park, E., Replogle, R., Boileau, T., . . . Edirisinghe, I. (2019). Enzyme-treated orange pomace alters acute glycemic response to orange juice. Nutrition and Diabetes, 9, 24. doi:10.1038/s41387-019-0091-z

Abstract:

The goal of the present study was to determine the impact of the addition of enzyme-treated orange pomace to orange juice on postprandial glycemic response. Ten healthy subjects (aged 27.9 ± 7.7 years, body mass index 22.1 ± 1.1 kg m−2) participated in a randomized, 2-arm, cross-over clinical trial to test the glycemic response to 100% orange juice (OJ) or 100% orange juice with 5 g of enzyme-treated orange pomace fiber (OPF). Blood samples were collected and glucose and insulin concentrations were measured at fasting (0 min) and every 15 min for 2 h after consuming the study juice products. Analysis of the 2 h incremental area under the curve (iAUC0–2h) indicated a significant reduction in blood glucose after ingesting the OPF juice compared to the OJ, p = 0.02. Peak glucose concentrations were also lowered after the OPF juice compared to the OJ, p < 0.05. No significant difference was observed in insulin responses between treatments, p > 0.05. Overall, this study demonstrated that adding 5 g of fiber from orange pomace into a serving of OJ attenuated the postprandial glucose response.

Sylvetsky, A. C., Hiedacavage, A., Shah, N., Pokorney, P., . . . Dietz, W. H. (2019). From biology to behavior: A cross-disciplinary seminar series surrounding added sugar and low-calorie sweetener consumption. Obesity Science and Practice, 5(3), 203-219. doi:10.1002/osp4.334

Abstract:

Introduction: This report presents a synopsis of a three-part, cross-sector, seminar series held at the George Washington University (GWU) in Washington, DC from February–April, 2018. The overarching goal of the seminar series was to provide a neutral forum for diverse stakeholders to discuss and critically evaluate approaches to address added sugar intake, with a key focus on the role of low-calorie sweeteners (LCS). Methods: During three seminars, twelve speakers from academic institutions, federal agencies, non-profit organizations, and the food and beverage industries participated in six interactive panel discussions to address: 1) Do Farm Bill Policies Impact Population Sugar Intake? 2) What is the Impact of Sugar-sweetened Beverage (SSB) Taxes on Health and Business? 3) Is Sugar Addictive? 4) Product Reformulation Efforts: Progress, Challenges, and Concerns? 5) Low-calorie Sweeteners: Helpful or Harmful, and 6) Are Novel Sweeteners a Plausible Solution? Discussion of each topic involved brief 15-minute presentations from the speakers, which were followed by a 25-minute panel discussion moderated by GWU faculty members and addressed questions generated by the audience. Sessions were designed to represent opposing views and stimulate meaningful debate. Given the provocative nature of the seminar series, attendee questions were gathered anonymously using Pigeonhole™, an interactive, online, question and answer platform. Results: This report summarizes each presentation and recapitulates key perspectives offered by the speakers and moderators. Conclusions: The seminar series set the foundation for robust cross-sector dialogue necessary to inform meaningful future research, and ultimately, effective policies for lowering added sugar intakes.

Wolever, T. M. S., Jones, P. J. H., Jenkins, A. L., Mollard, R. C., . . . Chu, Y. F. (2019). Glycaemic and insulinaemic impact of oats soaked overnight in milk vs. cream of rice with and without sugar, nuts, and seeds: A randomized, controlled trial. European Journal of Clinical Nutrition, 73(1), 86-93. doi:10.1038/s41430-018-0329-1

Abstract:

Background/Objectives: Soaking oats overnight in milk renders them ready to eat the next morning, however, it is unknown whether oats prepared this way will retain its relatively low glycaemic and insulinaemic impact. Therefore, we compared the glycaemic, insulinaemic and subjective hunger responses elicited by oats soaked overnight in 110 g skim-milk (ONO) vs. cooked cream of rice cereal (CR), both with and without inclusions. Subjects/Methods: The project was performed at two research centers (Toronto, Winnipeg) as two separate studies each using a randomized, cross-over design with similar methods. The glycaemic and insulinaemic responses of overnight-fasted participants without diabetes (males:females: Toronto, 24:16; Winnipeg, 20:20) were measured for 3 h after consuming CR and ONO fed alone (Toronto) or with added sugar, nuts, and seeds (CRsns and ONOsns) (Winnipeg). Participants rated subjective hunger using visual analog scales. Data were analyzed by paired t-test. The primary endpoint was 0–2 h incremental area under the curve (iAUC) for glucose. Results: Mean glucose iAUC was 33% less, after ONO than CR (mean difference was 39 (51–27) mmol × min/l, p < 0.0001) and 24% less, after ONOsns than CRsns (mean difference was 43 (65–21) mmol × min/l, p = 0.0003). Serum-insulin iAUC was 33% less, after ONO than CR (mean difference 57 (81–40) pmol × hl, p < 0.0001) and 32% less, after ONOsns than CRsns (966 (1360–572) pmol × h/l, p < 0.0001). In both Toronto and Winnipeg, subjective hunger ratings were similar across the two treatments. Conclusions: Oats prepared by soaking overnight in skimmed milk without and with inclusions retain their relatively low glycaemic and insulinaemic impact.

Volokh, O., Klimenko, N., Berezhnaya, Y., Tyakht, A., . . . Alexeev, D. (2019). Human gut microbiome response induced by fermented dairy product intake in healthy volunteers. Nutrients, 11(3), 547. doi:10.3390/nu11030547

Abstract:

Accumulated data suggests that the gut microbiome can rapidly respond to changes in diet. Consumption of fermented dairy products (FDP) fortified with probiotic microbes may be associated with positive impact on human health. However, the extent and details of the possible impact of FDP consumption on gut community structure tends to vary across individuals. We used microbiome analysis to characterize changes in gut microbiota composition after 30 days of oral intake of a yoghurt fortified with Bifidobacterium animalis subsp. lactis BB-12. 16S rRNA gene sequencing was used to assess the gut microbial composition before and after FDP consumption in healthy adults (n = 150). Paired comparison of gut microbial content demonstrated an increase in presence of potentially beneficial bacteria, particularly, Bifidobacterium genus, as well as Adlercreutzia equolifaciens and Slackia isoflavoniconvertens. At a functional level, an increased capacity to metabolize lactose and synthesize amino acids was observed accompanied by a lowered potential for synthesis of lipopolysaccharides. Cluster analysis revealed that study volunteers segregated into two groups with post-intervention microbiota response that was dependent on the baseline microbial community structure.

Wolever, T. M. S., Johnson, J., Jenkins, A. L., Campbell, J. C., . . . Chu, Y. (2019). Impact of oat processing on glycaemic and insulinaemic responses in healthy humans: A randomised clinical trial. British Journal of Nutrition, 121(11), 1264-1270. doi:10.1017/S0007114519000370

Abstract:

Oats can be processed in a variety of ways ranging from minimally processed such as steel-cut oats (SCO), to mildly processed such as large-flake oats (old fashioned oats, OFO), moderately processed such as instant oats (IO) or highly processed in ready-to-eat oat cereals such as Honey Nut Cheerios (HNC). Although processing is believed to increase glycaemic and insulinaemic responses, the effect of oat processing in these respects is unclear. Thus, we compared the glycaemic and insulinaemic responses elicited by 628 kJ portions of SCO, OFO, IO and HNC and a portion of Cream of Rice cereal (CR) containing the same amount of available-carbohydrate (23 g) as the oatmeals. Healthy males (n 18) and females (n 12) completed this randomised, cross-over trial. Blood was taken fasting and at intervals for 3 h following test-meal consumption. Glucose and insulin peak-rises and incremental AUC (iAUC) were subjected to repeated-measures ANOVA using Tukey’s test (two-sided P<0·05) to compare individual means. Glucose peak-rise (primary endpoint, mean (SEM) mmol/l) after OFO, 2·19 (SEM 0·11), was significantly less than after CR, 2·61 (SEM 0·13); and glucose peak-rise after SCO, 1·93 (SEM 0·13), was significantly less than after CR, HNC, 2·49 (SEM 0·13) and IO 2·47 (SEM 0·13). Glucose iAUC was significantly lower after SCO than CR and HNC. Insulin peak rise was similar among the test meals, but insulin iAUC was significantly less after SCO than IO. Thus, the results show that oat processing affects glycaemic and insulinaemic responses with lower responses associated with less processing.

Schuster, J., & Mitchell, E. S. (2019). More than just caffeine: Psychopharmacology of methylxanthine interactions with plant-derived phytochemicals. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 89, 263-274. doi:10.1016/j.pnpbp.2018.09.005

Abstract:

In general, preparations of coffee, teas, and cocoa containing high levels of polyphenols, L-theanine and other bioactive compounds selectively enhance mood and cognition effects of caffeine. This review summarizes the bioactive components of commonly consumed natural caffeine sources (e.g. guayusa, mate and camellia teas, coffee and cocoa) and analyzes the psychopharmacology of constituent phytochemicals: methylxanthines, polyphenols, and L-theanine. Acute and chronic synergistic effects of these compounds on mood and cognition are compared and discussed. Specific sets of constituent compounds such as polyphenols, theobromine and L-theanine appear to enhance mood and cognition effects of caffeine and alleviate negative psychophysiological effects of caffeine. However, more research is needed to identify optimal combinations and ratios of caffeine and phytochemicals for enhancement of cognitive performance.

Liska, D., Mah, E., Brisbois, T., Barrios, P. L., . . . Spriet, L. L. (2019). Narrative review of hydration and selected health outcomes in the general population. Nutrients, 11(1), 70. doi:10.3390/nu11010070

Abstract:

Although adequate hydration is essential for health, little attention has been paid to the effects of hydration among the generally healthy population. This narrative review presents the state of the science on the role of hydration in health in the general population, specifically in skin health, neurological function (i.e., cognition, mood, and headache), gastrointestinal and renal functions, and body weight and composition. There is a growing body of evidence that supports the importance of adequate hydration in maintaining proper health, especially with regard to cognition, kidney stone risk, and weight management. However, the evidence is largely associative and lacks consistency, and the number of randomized trials is limited. Additionally, there are major gaps in knowledge related to health outcomes due to small variations in hydration status, the influence of sex and sex hormones, and age, especially in older adults and children.

Pavadhgu, P., Bumrungpert, A., Harjani, Y., & Kurilich, A. (2019). Oat porridge consumption alleviates markers of inflammation and oxidative stress in hypercholesterolemic adults. Asia Pacific Journal of Clinical Nutrition, 28(2), 260-265. doi:10.6133/apjcn.201906_28(2).0008

Abstract:

Background and Objectives: Oats contain antioxidant phytochemicals that may help reduce inflammation as well as oxidative stress. In this study we aimed to investigate the effect of oat porridge consumption on inflammatory marker levels and oxidative stress in Thai adults with high blood lipid levels. Methods and Study Design: A randomized crossover study was conducted. Hypercholesterolemic adults were randomly assigned to a 4-week daily consumption of oat or rice porridge. After 4 weeks, they were switched to alternate intervention arms for 4 weeks. At baseline, before and after each intervention period, inflammatory markers including hsCRP, IL-6, IL-8, TNF-α, and MCP-1 and antioxidant status markers including ORAC, FRAP, and MDA of all subjects were measured. Results: Compared to baseline, levels of hsCRP, IL-6, IL-8, and TNF-α were significantly decreased after oat porridge consumption (mean change: -0.6&#177;0.9 mg/L, -26.9&#177;27.6 pg/mL, -56.3&#177;27.6 pg/mL, and - 9.7&#177;11.6 pg/mL, p＜0.05 for all, respectively). In addition, consumption of oat porridge also increased antioxidant capacity; ORAC and FRAP levels (mean change: 2.7&#177;1.0 μmol of Trolox/L and 2.4&#177;0.8 μmol of Fe^(2+)/L, p＜0.001, respectively). However, MCP-1 and MDA levels were not affected. Consumption of rice porridge did not lead to significant changes in these measures. Conclusions: Daily consumption of 70 grams oat porridge containing 3 grams β-glucan for 4 weeks may help reduce markers of inflammation and oxidation in hypercholesterolemic adults. Therefore, oat may be an appropriate dietary recommendation for individuals with hypercholesterolemia.

Fulgoni, V. L., Brauchla, M., Fleige, L., & Chu, Y. (2019). Oatmeal-containing breakfast is associated with better diet quality and higher intake of key food groups and nutrients compared to other breakfasts in children. Nutrients, 11(5), 964. doi:10.3390/nu11050964

Abstract:

Oatmeal is a whole grain (WG) food rich in fiber and other nutrients. The study objective was to compare diet quality and nutrient intake of children consuming oatmeal breakfasts to those of children consuming other breakfasts using the National Health and Nutrition Examination Survey (NHANES) 2011–2014. Dietary intake data from 5876 children aged 2–18 years were divided by breakfast food consumption: oatmeal breakfasts, “Doughnuts, sweet rolls, pastries”, “Pancakes, waffles, French toast”, “Eggs and omelets”, “Ready-to-eat cereal, lower sugar”, and “Ready-to-eat cereal, higher sugar” were used to assess diet quality and intake of food groups and nutrients using the USDA Healthy Eating Index-2015 (HEI-2015), Food Patterns Equivalents Database, and Food and Nutrient Database for Dietary Studies, respectively. As compared to consumers of other breakfasts or breakfast skippers, oatmeal consumers had consistently higher diet quality (4–16 points higher HEI 2015 total score, p < 0.05), higher WG intake (0.6–1.6 oz eq. higher, p < 0.05), and higher fiber and magnesium intakes compared to consumers of most other breakfasts or breakfast skippers. The results show that children consuming oatmeal breakfasts have better diet quality and increased intake of key nutrients compared to breakfast skippers and other breakfast consumers and suggest oatmeal may represent an important component of a healthy childhood diet.

Joyce, S. A., Kamil, A., Fleige, L., & Gahan, C. G. M. (2019). The cholesterol-lowering effect of oats and oat β-glucan: Modes of action and potential role of bile acids and the microbiome. Frontiers in Nutrition, 6, 171. doi:10.3389/fnut.2019.00171

Abstract:

Consumption of sufficient quantities of oat products has been shown to reduce host cholesterol and thereby modulate cardiovascular disease risk. The effects are proposed to be mediated by the gel-forming properties of oat β-glucan which modulates host bile acid and cholesterol metabolism and potentially removes intestinal cholesterol for excretion. However, the gut microbiota has emerged as a major factor regulating cholesterol metabolism in the host. Oat β-glucan has been shown to modulate the gut microbiota, particularly those bacterial species that influence host bile acid metabolism and production of short chain fatty acids, factors which are regulators of host cholesterol homeostasis. Given a significant role for the gut microbiota in cholesterol metabolism it is likely that the effects of oat β-glucan on the host are multifaceted and involve regulation of microbe-host interactions at the gut interface. Here we consider the potential for oat β-glucan to influence microbial populations in the gut with potential consequences for bile acid metabolism, reverse cholesterol transport (RCT), short-chain fatty acid (SCFA) production, bacterial metabolism of cholesterol and microbe-host signaling.

Vieux, F., Maillot, M., Rehm, C. D., Barrios, P., & Drewnowski, A. (2019). The timing of water and beverage consumption during the day among children and adults in the United States: Analyses of NHANES 2011–2016 data. Nutrients, 11(11), 2707. doi:10.3390/nu11112707

Abstract:

Dietary Guidelines for Americans 2015–20 recommend replacing sugar sweetened beverages (SSBs) with plain water in order to promote adequate hydration while reducing added sugar intake. This study explored how water intakes from water, beverages, and foods are distributed across the day. The dietary intake data for 7453 children (4–18 y) and 15,263 adults (>19 y) came from the National Health and Nutrition Examination Survey (NHANES 2011–2016). Water was categorized as tap or bottled. Beverages were assigned to 15 categories. Water intakes (in mL/d) from water, beverages, and food moisture showed significant differences by age group, meal occasion, and time of day. Plain water was consumed in the morning, mostly in the course of a morning snack and between 06:00 and 12:00. Milk and juices were consumed at breakfast whereas SSBs were mostly consumed at lunch, dinner, and in the afternoon. Children consumed milk and juices, mostly in the morning. Adults consumed coffee and tea in the morning, SSBs in the afternoon, and alcohol in the evening. Relatively little drinking water was consumed with lunch or after 21:00. Dietary strategies to replace caloric beverages with plain water need to build on existing drinking habits by age group and meal type.

Olson, A., Frankenfeld, C. L., Wallace, T. C., & Johnson, J. (2018). Assessment of oats and milk on markers of cardiovascular disease: National Health and Nutrition Examination Survey 1999-2014 data sets. Nutrition Today, 53(6), 293-299. doi:10.1097/NT.0000000000000308

Abstract:

Background: Oat consumption has been suggested to decrease the risk of cardiovascular disease; oats are frequently co-consumed with milk, but also water and other products. Methods: We evaluated associations of 24-hour self-reported oat and cow’s milk consumption with cardiovascular disease risk factors using National Health and Nutrition Examination Survey (1999–2014) data. Daily oat and milk consumptions were classified as (1) no oats, no milk; (2) yes oats, no milk; (3) no oats, yes milk; or (4) yes oats, yes milk. We used no oats/no milk as a reference to assess the effects of oats, milk, and oat with milk consumption on markers of cardiovascular disease (CVD). The yes oats/no milk group was then used as the reference to further determine if a relationship between oat and milk consumption on the same day existed past that of previously reported oat consumption alone. Results: Self-reported oat intake was associated with improvements in some biomarkers of CVD risk. The prevalence of abdominal obesity measured as waist circumference was lower (odds ratio, 0.57; 95% confidence interval, 0.41–0.73), and fewer than 3+ risk factors of metabolic syndrome (odds ratio, 0.66; 95% confidence interval, 0.51–0.85) were observed in the yes oats/yes milk group as compared with nonconsumers (no oats/no milk). Similar effects were found in the yes oats/no milk group. We did not find any synergistic effects of self-reported consumption of both milk and oats during a 24-hour period on markers of CVD. Conclusions: These results are consistent with clinical data showing oats to be associated with improvement in some biomarkers of CVD risk; however, the addition of milk does not appear to affect CVD risk factors in this cross-sectional data set.

Bolster, D. R., Rahn, M., Kamil, A. G., Bristol, L. T., . . . Harkness, L. (2018). Consuming lower-protein nutrition bars with added leucine elicits postprandial changes in appetite sensations in healthy women. The Journal of Nutrition, 148(5), 693-701. doi:10.1093/jn/nxy023

Abstract:

Background: Higher-protein meals (>25 g protein/meal) have been associated with enhanced satiety but the role of amino acids is unclear. Leucine has been proposed to stimulate satiety in rodents but has not been assessed in humans. Objective: We assessed the acute effects of lower-protein nutrition bars, enhanced with a leucine peptide (LP), on postprandial appetite sensations in combination with plasma leucine and peptide YY (PYY) in healthy women. Methods: Utilizing a double-blind randomized crossover design, 40 healthy women [28 ± 7.5 y; body mass index (BMI, in kg/m2): 23.5 ± 2.4] consumed the following isocaloric (180 kcal) pre-loads on 3 separate visits: control bar [9 g protein with 0 g added LP (0-g LP)] or treatment bars [11 g protein with 2 g added LP (2-g LP) or 13 g protein with 3 g added LP (3-g LP)]. Pre- and postprandial hunger, desire to eat, prospective food consumption (PFC), fullness, and plasma leucine were assessed every 30 min for 240 min. Plasma PYY was assessed hourly for 240 min (n = 24). Results: Main effects of time (P < 0.0001) and treatment (P < 0.03) were detected for postprandial hunger, desire to eat, PFC, and fullness. Post hoc analyses revealed that the 2-g and 3-g LP bars elicited greater increases in fullness and greater decreases in PFC compared with 0-g LP (all, P < 0.05) with no differences between the 2-g and 3-g LP bars. The 2-g bar elicited greater decreases in hunger and desire to eat compared with the 0-g LP bar (both, P ≤ 0.01), whereas 3-g LP did not. Appetite incremental areas under the curves (iAUCs) and PYY outcomes were not different between bars. A treatment × time interaction was detected for plasma leucine with increases occurring in a leucine-dose–dependent manner (P < 0.0001). Conclusion: Despite the dose-dependent increases in plasma leucine following the consumption of lower-protein bars enhanced with LP, only the 2-g LP bar elicited consistent postprandial changes in select appetite sensations compared with the 0-g LP bar. This study was registered on clinicaltrials.gov as NCT02091570.

Fleige, L., Bhoite, R., Marwaha, A., & Glahn, R. (2018). Development of a fortified juice beverage: Assessment of iron bioavailability using an established Caco-2 cell bioassay. Journal of Nutritional Health & Food Science, 6(3), 1-7. doi:10.15226/jnhfs.2018.001133

Abstract:

Poor iron bioavailability is a contributing factor to the high prevalence of iron deficiency anemia in India, and food fortification with bioavailable iron is one strategy to help address the problem. Validated in vitro methods to measure iron (Fe) bioavailability are useful tools that can be leveraged to estimate the bioavailability of Fe in foods and beverages. In the present study, the objective was to determine if 15% of the Indian Recommended Dietary Allowance (RDA) of Fe as Micronized Iron Pyrophosphate (MIP) in 200 mL (i.e. 3.2 mg Fe per 200 mL) of a fortified mixed Fruit and Vegetable Juice Beverage (FJB) provides bioavailable Fe. To test this objective, various amounts of MIP were added to the FJB with 3 different levels of ascorbic acid (i.e. vitamin C; a known enhancer of Fe bioavailability and an essential nutrient). Vitamin A (retinyl acetate) at a level of 90 μg/200 mL was also added to all samples, except for some controls. The results demonstrated that 15% RDA of Fe (as MIP) in a 200 mL serving of juice fortified with equimolar ascorbic acid resulted in good Fe bioavailability for this form of Fe. Overall, the study demonstrated that a FJB product could be developed to be an excellent source of dietary Fe.

Van Den Abbeele, P., Kamil, A., Fleige, L., Chung, Y., . . . Marzorati, M. (2018). Different oat ingredients stimulate specific microbial metabolites in the gut microbiome of three human individuals in vitro. ACS Omega, 3(10), 12446-12456. doi:10.1021/acsomega.8b01360

Abstract:

We used a standardized in vitro simulation of the intestinal environment of three human donors to investigate the effect of six oat ingredients, which were produced by the application of different processing techniques, on the gut microbial community. Fructooligosaccharide was used as the positive control. Consistent changes in pH and gas production, on average −0.4 pH units and +32 kPa, indicated the high fermentability of the oat ingredients, and the resulting increased production of metabolites that are considered as beneficial for human health. These metabolites included acetate and lactate, but mostly propionate (+13.6 mM on average). All oat ingredients resulted in increased bifidobacteria levels with an average increase of 0.73 log. Moreover, a decreased production of proteolytic markers was observed, including branched short-chain fatty acids and ammonium. The results were donor-specific and product-specific. The results suggested an association between the total amounts of dietary fiber and the prebiotic potentials of different ingredients. Furthermore, as mechanical processing of oat products has previously been linked to increased extractability of dietary fibers, the obtained results suggest that different processing techniques might have impacted the potential functional properties of the final ingredients.

Wolever, T. M. S., Jenkins, A. L., Prudence, K., Johnson, J., . . . Steinert, R. E. (2018). Effect of adding oat bran to instant oatmeal on glycaemic response in humans - A study to establish the minimum effective dose of oat β-glucan. Food and Function, 9(3), 1692-1700. doi:10.1039/c7fo01768e

Abstract:

Reducing the glycaemic response to carbohydrate-containing foods may have desirable physiological effects for many people. Here, we aimed to determine the minimum amount of oat β-glucan from oat-bran which, when added to instant-oatmeal, would reduce the glycaemic response by 20% compared to a β-glucan-free cereal. Therefore, the glycaemic responses elicited by one serving (27 g) instant-oatmeal plus 247 g 2% milk (IO, 28 g available-carbohydrate, 1.2 g β-glucan) or IO plus 0.2, 0.4, 0.8 or 1.6 g oat β-glucan (OBG) from oat-bran, or an available-carbohydrate matched portion of cream of rice (CR) plus milk were measured over 2 h in n = 40 subjects using a randomized, cross-over design. The primary endpoint was incremental area under the curve (iAUC). The secondary endpoint was glucose peak-rise. The results showed that grams OBG consumed were significantly correlated with mean iAUC (p = 0.009) and with mean glucose peak-rise (p = 0.002). Each gram of OBG reduced iAUC by 7% and peak-rise by 15%. Thus, to achieve a ≥20% reduction in iAUC relative to CR, 1.6 g OBG had to be added to IO (74 ± 7 vs. 93 ± 6 mmol min L−1, p < 0.05), but, to achieve a 20% reduction in peak-rise, only 0.4 g OBG was required (2.00 ± 0.1 vs. 2.40 ± 0.1 mmol, p < 0.05). We conclude that adding OBG to IO flattened postprandial glycaemic responses in a dose-dependent fashion; 1.6 g OBG was required to reduce iAUC by ≥20% versus CR, but a 20% reduction in peak-rise required only 0.4 g. The greater effect of OGB on peak-rise than iAUC presumably reflects the way viscous dietary fibres modulate glucose absorption kinetics.