Health & Nutrition Sciences Publications

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±0.9 mg/L, -26.9±27.6 pg/mL, -56.3±27.6 pg/mL, and - 9.7±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±1.0 μmol of Trolox/L and 2.4±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.

Rebello, C. J., Johnson, W. D., Martin, C., Johnson, J., . . . Greenway, F. L. (2018). Effect of two oat-based cereal on subjective ratings of appetite. Current Topics in Nutraceutical Research, 16, 113-120.

Abstract

Viscosity generated by oat β-glucan induces gastrointestinal mechanisms that influence appetite. Two oat-based ready-to-eat cereals (RTEC) with similar amounts of β-glucan but differing in their protein and sugar content were compared for their effects on appetite. Forty-seven healthy individuals, ≥18 years old, enrolled in a crossover trial consumed RTEC1 or RTEC2 in random order at least a week apart. Breakfasts contained 250kcals cereal and 105kcals fat-free milk. Subjective ratings of appetite were completed at baseline, and at 30, 60, 120, 180 and 240 minutes after consumption of the breakfast meals. Responses were analyzed as area under the curve (AUC) and per time-point. Significance was set at α=0.05. Fullness (p=0.01) and stomach fullness (p=0.02) were greater with RTEC 1 compared to RTEC 2 at 240 minutes. Stomach fullness (p=0.01) was greater at 30 minutes, and desire to eat (p=0.04) was reduced at 120 minutes with RTEC2 compared to RTEC1. There was no difference in the AUC for hunger, fullness, stomach fullness, desire to eat, or prospective intake. Ready-to-eat cereals containing similar amounts of oat β-glucan differed in the timing of significant differences in fullness or desire to eat, but appetite ratings over a four hour period did not differ.

AlHasawi, F. M., Fondaco, D., Corradini, M. G., Ludescher, R. D., . . . Rogers, M. A. (2018). Gastric viscosity and sugar bioaccessibility of instant and steel cut oat/milk protein blends. Food Hydrocolloids, 82, 424-433. doi:10.1016/j.foodhyd.2018.04.014

Abstract

Milk protein concentrate (MPC; 0 g, 5 g, and 10 g) was added to two commercially available oat products (instant oats and steel cut oats) to examine how MPC addition, and consequent changes in meal formulation, manipulates both gastric lumen viscosity and intestinal carbohydrate-digestion kinetics, in vitro. We used the TNO Intestinal Model-1 (TIM-1) to simulate gastrointestinal digestion of the oats-based meals. Meals containing 5 g or 10 g MPC yielded significantly less total bioaccessible sugar compared with those containing 0 g MPC, while the rate of starch digestion was significantly higher in meals containing 5 g or 10 g MPC. The TIM-1 was coupled with fluorescence spectroscopy and a luminescent molecular rotor to report changes in gastric viscosity in situ, showing that the gastric viscosity was higher in the meals containing MPC. Those findings suggest that MPC in oats-based meals significantly modifies the kinetics of carbohydrate digestion and increases gastric viscosity.

Kock, L. B., Brummer, Y., Exley, T., Rhymer, C., . . . Bordenave, N. (2018). In vitro assessment of oat β-glucans nutritional properties: An inter-laboratory methodology evaluation. Carbohydrate Polymers, 200, 271-277. doi:10.1016/j.carbpol.2018.07.082

Abstract

The purpose of this inter-laboratory study was to test the repeatability and reproducibility of an in vitro method aimed at analyzing the physicochemical properties under physiological conditions of β-glucans from foods. After evaluating β-glucans molar mass and quantification methods using five β-glucan controls, four laboratories ran six oat-based products through in vitro digestion, measured β-glucans solubility and viscosity and molar mass of solubilized β-glucans. The determination of the molar mass of β-glucan controls, their viscosity in solution and β-glucans content in food samples exhibited relative standard reproducibility of 20.9–40.9%, 10.2–40.9% and 2.3–14.8%, respectively. After in vitro digestion, relative standard reproducibility ranged 12.1–60.0%, 12.2–64.3% and 9.7–36.3% for molar mass of extracted β-glucans, their viscosity and their solubility, respectively. Although the characterization methods were satisfactory within the limits of current technology, the in vitro extraction contributed significantly to the uncertainty of final characterization.

Devries, M. C., McGlory, C., Bolster, D. R., Kamil, A., . . . Phillips, S. M. (2018). Leucine, not total protein, content of a supplement is the primary determinant of muscle protein anabolic responses in healthy older women. The Journal of Nutrition, 148(7), 1088-1095. doi:10.1093/jn/nxy091

Abstract

Background: Older adults show a blunted muscle protein synthesis (MPS) response to postprandial hyperaminoacidemia relative to younger adults. Evidence suggests that this anabolic resistance can be overcome by consuming greater quantities of leucine. Objective: The purpose of this trial was to determine whether the addition of leucine to a smaller dose (10 g) of milk proteins would, when compared with a larger dose (25 g) of whey protein isolate (WPI), result in similar increases in acute (hourly) and integrated (daily) myofibrillar protein synthesis (myoPS). Methods: Healthy older (mean ± SD age: 69 ± 1 y) women (n = 11/group) were randomly assigned with the use of a single-blind, parallel-group design to twice-daily consumption of either WPI [25 g WPI (3 g L-leucine)] or leucine (LEU; 10 g milk protein with 3 g total L-leucine) for 6 d. Participants performed unilateral resistance exercise to allow assessment of the impact of the supplement alone and with resistance exercise. We determined acute (13C6-phenylanine) and integrated [using deuterated water (D2O)] rates of myoPS in the fasting (acute), basal (integrated), nonexercised, and exercised states. Results: Acute myoPS increased in both legs in response to LEU (fed: 45%; fed+exercise: 71%; P < 0.001) and WPI (fed: 29%; fed+exercise: 47%; P < 0.001) compared with fasting; the increase was greater with LEU than with WPI in the exercised leg (46%; P = 0.04) but not in the rested leg (P = 0.07). The acute myoPS response was greater in the exercised leg than in the rested leg for both WPI (63%) and LEU (58%) (P < 0.001). Integrated myoPS increased with WPI and LEU in the exercised leg (both 9%; P < 0.001) during supplementation, and with WPI (3%; P = 0.02) but not LEU (2%, P = 0.1) in the rested leg compared with the basal state. Conclusions: A lower-protein (10 compared with 25 g/dose), leucine-matched beverage induced similar increases in acute and integrated myoPS in healthy older women. Lower-protein supplements with added leucine may represent an advantageous approach in older adults to maintain skeletal muscle anabolic sensitivity and attenuate muscle loss; however, further work is needed using longer-term interventions to substantiate these findings. This trial was registered at www.clinicaltrials.gov as NCT02282566.

DellaValle, D. M., Malek, A. M., Hunt, K. J., Peter, J. V., . . . Marriott, B. P. (2018). Low-calorie sweeteners in foods, beverages, and food and beverage additions: NHANES 2007-2012. Current Developments in Nutrition, 2(12). doi:10.1093/cdn/nzy024

Abstract

Background: Most publications about low-calorie sweeteners (LCSs) focus on person-level intake prevalence. Objective: We assessed LCS distribution in foods, beverages, and food and beverage additions (FBAs), e.g., mayonnaise, in the US adult diet as reported in the NHANES (2007-2012). Methods: Dietary items reported in the first 24-h recall were coded for LCS and/or nutritive sweeteners (NSs) with the use of USDA What We Eat in America food files. We calculated the number of times items were reported and LCS/NS content. Results: Of reported items, 56.1% were foods, 29.1% were beverages, and 14.8% were FBAs. LCS was contained in 0.7% of foods, 8.1% of beverages, and 10.4% of FBAs. This food-level analysis identified FBAs as a significant source of LCSs in the US diet. Conclusion: Identifying the diversity of LCS and NS sources will enhance exposure classification for examining diet and health relations, including body weight management.

Marriott, B. P., Hunt, K. J., Malek, A. M., St. Peter, J. V., & Greenberg, D. (2018). Low-calorie sweeteners: Exploring underutilized database resources to understand dietary patterns and obesity. Obesity, 26, S5-S8. doi:10.1002/oby.22261

Abstract

The use and impact of low-calorie sweeteners (LCS) in relation to the national challenges of overweight and obesity are complex and controversial. Most research on LCS have focused on the prevalence of consumption of LCS in beverages. The 2015 Dietary Guidelines Advisory Committee emphasized dietary patterns and health rather than a focus on specific nutrients or foods. The committee took this approach to shift the national emphasis onto the context of total rather than individual nutrient consumption. A broader research paradigm is needed to elucidate the actual exposure to LCS and how they are consumed within dietary patterns in the US population. National-level databases exist that can be used to broaden scientific understanding of the effects of LCS and health outcomes. These databases are underutilized, and they provide potential tools for grasping a fuller picture of LCS in the US diet.

Wilson, T. J., Gray, M. J., Van Klinken, J.W., Kaczmarczyk, M., & Foxe, J. J. (2018). Macronutrient composition of a morning meal and the maintenance of attention throughout the morning. Nutritional Neuroscience, 21(10), 729-743. doi:10.1080/1028415X.2017.1347998

Abstract

Background: At present, the impact of macronutrient composition and nutrient intake on sustained attention in adults is unclear, although some prior work suggests that nutritive interventions that engender slow, steady glucose availability support sustained attention after consumption. A separate line of evidence suggests that nutrient consumption may alter electroencephalographic markers of neurophysiological activity, including neural oscillations in the alpha-band (8–14 Hz), which are known to be richly interconnected with the allocation of attention. It is here investigated whether morning ingestion of foodstuffs with differing macronutrient compositions might differentially impact the allocation of sustained attention throughout the day as indexed by both behavior and the deployment of attention-related alpha-band activity. Methods: Twenty-four adult participants were recruited into a three-day study with a cross-over design that employed a previously validated sustained attention task (the Spatial CTET). On each experimental day, subjects consumed one of three breakfasts with differing carbohydrate availabilities (oatmeal, cornflakes, and water) and completed blocks of the Spatial CTET throughout the morning while behavioral performance, subjective metrics of hunger/fullness, and electroencephalographic (EEG) measurements of alpha oscillatory activity were recorded. Results: Although behavior and electrophysiological metrics changed over the course of the day, no differences in their trajectories were observed as a function of breakfast condition. However, subjective metrics of hunger/fullness revealed that caloric interventions (oatmeal and cornflakes) reduced hunger across the experimental day with respect to the non-caloric, volume-matched control (water). Yet, no differences in hunger/fullness were observed between the oatmeal and cornflakes interventions.Conclusion: Observation of a relationship between macronutrient intervention and sustained attention (if one exists) will require further standardization of empirical investigations to aid in the synthesis and replicability of results. In addition, continued implementation of neurophysiological markers in this domain is encouraged, as they often produce nuanced insight into cognition even in the absence of overt behavioral changes.

Moser, S., Aragon, I., Furrer, A., Van Klinken, J. W., . . . Ferruzzi, M. G. (2018). Potato phenolics impact starch digestion and glucose transport in model systems but translation to phenolic rich potato chips results in only modest modification of glycemic response in humans. Nutrition Research, 52, 57-70. doi:10.1016/j.nutres.2018.02.001

Abstract

Beneficial effects of some phenolic compounds in modulation of carbohydrate digestion and glycemic response have been reported, however effects of phenolics from processed potato products on these endpoints are not well known. The aims of this study were to characterize phenolic profiles of fresh potatoes (purple, red, or white fleshed; 2 varieties each) and chips, and to examine the potential for potato phenolic extracts (PPE) to modulate starch digestion and intestinal glucose transport in model systems. Following in vitro assessment, a pilot clinical study (n=11) assessed differences in glycemic response and gastric emptying between chips from pigmented and white potatoes. We hypothesized that phenolics from pigmented potato chips would be recovered through processing and result in a reduced acute glycemic response in humans relative to chips made from white potatoes. PPEs were rich in anthocyanins (~98, 11 and ND mg/100 g dw) and chlorogenic acids (~519, 425 and 157 mg/100 g dw) for purple, red and white varieties respectively. While no significant effects were observed on starch digestion by α-amylase and the α-glucosidases, PPEs significantly (p<0.05) decreased the rate of glucose transport, measured following transport of 1,2,3,4,5,6,6-d7 -glucose (d7-glu) across Caco-2 human intestinal cell monolayers, by 4.5-83.9%. Consistent with in vitro results, consumption of purple potato chips modestly but significantly (p<0.05) decreased blood glucose at 30 and 60 minutes post consumption compared to white chips without impacting gastric emptying. These results suggest that potato phenolics may play a modest role in modulation of glycemic response and these effects may result in subtle differences between consumer products.

Devries, M. C., McGlory, C., Bolster, D. R., Kamil, A., . . . Phillips, S. M. (2018). Protein leucine content is a determinant of shorter-and longer-term muscle protein synthetic responses at rest and following resistance exercise in healthy older women: A randomized, controlled trial. American Journal of Clinical Nutrition, 107(2), 217-226. doi:10.1093/ajcn/nqx028

Abstract:

Background: Older women may not be consuming enough protein to maintain muscle mass. Augmentation of protein intake with leucine may enhance the muscle protein synthetic response in older women to aid in maintaining muscle mass. Objective: We measured the acute (hourly) and integrated (daily) myofibrillar protein synthesis (myoPS) response to consumption of a high-quality mixed protein beverage compared with an isonitrogenous protein beverage with added leucine. Design: In a parallel design, free-living, healthy older women (aged 65–75 y, n = 11/group) consumed a fixed, weight-maintaining diet with protein at 1.0 g · kg–1 · d–1 and were randomly assigned to twice-daily consumption of either 15 g milk protein beverage containing 4.2 g leucine (LEU) or 15 g mixed protein (milk and soy) beverage containing 1.3 g leucine (CON). Unilateral leg resistance exercise allowed a determination of acute ([13C6]-phenylalanine infusion, hourly rate) and integrated (deuterated water ingestion, daily rate) exercised and rested myoPS responses. Results: Acute myoPS increased in response to feeding in the rested (CON: 13% ± 4%; LEU: 53% ± 5%) and exercised (CON: 30% ± 4%; LEU: 87% ± 7%) leg in both groups, but the increase was greater in LEU (P < 0.001). Integrated myoPS increased during the supplementation period in both legs (rested: 9% ±1%; exercised: 17% ± 2%; P < 0.001) in LEU, but in the exercised leg only (7% ± 2%; P < 0.001) in CON. Conclusions: A 15-g protein-containing beverage with ∼4 g leucine induced greater increases in acute and integrated myoPS than did an isonitrogenous, isoenergetic mixed-protein beverage. Declines in muscle mass in older women may be attenuated with habitual twice-daily consumption of a protein beverage providing 15 g protein and higher (4.2 g/serving) amounts of leucine. This trial was registered at clinicaltrials.gov as NCT02282566.

Pasman, W. J., Hendriks, H. F. J., Minekus, M. M., de Ligt, R. A. F., . . . Bellmann, S. (2018). Subjective feelings of appetite of wholegrain breakfasts evaluated under controlled, laboratory and ‘at home’ conditions. Physiology and Behavior, 194, 285-291. doi:10.1016/j.physbeh.2018.06.024

Abstract

Background: Appetite regulating properties of foods are usually investigated under laboratory conditions, whereas in real life, foods are consumed under at home conditions. The objective of this study was to compare the acute effects of breakfasts when tested in a laboratory condition and in an at home condition. Appetite regulating properties of two bread breakfasts and two cereal breakfasts were also compared. Subjects and methods: In this randomized cross-over trial balanced for laboratory and at home test conditions, thirty-two women consumed five breakfasts, i.e. two bread breakfasts, two cereal breakfasts and one fried-egg breakfast. Visual analogue scales for measuring appetite were captured via an on-line scoring system and were analyzed as incremental area under the curve, as satiation phase and as satiety phase. Results: Location effects were limited to two small effects only. An overall location effect in hunger feelings was observed (p = 0.040), which occurred specifically during the short satiation period (p = 0.0002) where hunger feelings scored higher under laboratory conditions. Similarly, a location effect was observed for desire to eat (p = 0.001); this was again higher under laboratory conditions. No other location effects were observed. Bread breakfasts did not differ in their appetite regulating properties. The Steel Cut oatmeal breakfast was reported to be more satiating (p = 0.001) as compared to the ready-to-eat cereal. Conclusions: Whereas the five breakfasts varied somewhat in their appetite regulating properties, evaluation under laboratory conditions overall did not result in different appetite scores compared to the at home conditions. This suggests that at home testing may be a useful alternative to laboratory test conditions for nutrition research.