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Background: Sorghum is the fifth most consumed cereal grain but limiting in the indispensable amino acid lysine. Complementing sorghum with lentils can improve the quality of sorghum-based diets. However, knowledge of lysine bioavailability in sorghum is lacking.Objectives: The study objectives were to determine the bioavailability of lysine in sorghum and to assess the effect of complementation of sorghum and lentils in a mixed-meal format.Methods: We studied 5 healthy young men (≤30 years; BMI <25 kg/m2) in a repeated-measure design using the indicator amino acid oxidation (IAAO) method, with L-[1-13C] phenylalanine as the indicator. Each subject participated in 8 determinations in random order. On the reference diet, subjects received 4 amounts of L-lysine (5, 8, 12, and 15 mg. kg-1 . d-1) from a crystalline amino acid mixture patterned after egg protein. On the test diet, they received 3 levels of lysine (8.2, 12.5, and 15.7 mg. kg-1 . d-1) from sorghum, and on the complementation diet they received 1 level of lysine from a mixed meal of sorghum and lentils. The bioavailability of lysine in sorghum was estimated by comparing the IAAO response to the test diet with the IAAO response to the reference diet using the slope-ratio method. Effectiveness of complementation was assessed by comparing the IAAO response to the mixed meal to the IAAO response to the test protein.Results: The bioavailability of lysine from sorghum was 94%. Upon complementation with lentils, there was a decline in the oxidation of L-[1-13C] phenylalanine by 19% (P < 0.0495), reflecting an improvement in available lysine in the mixed meal due to increased lysine intake.Conclusions: Although the bioavailability of lysine in sorghum is high, its lysine content is limiting. Complementation with lentils in a 1:1 ratio is recommended to achieve the lysine requirement for adult men consuming a sorghum-based diet. This trial was registered at clinicaltrials.gov as NCT03411005. [ABSTRACT FROM AUTHOR]

Background: Accurate measurement of dietary intake is vital for providing nutrition interventions and understanding the complex role of diet in health. Traditional dietary assessment methods are very resource intensive and burdensome to participants. Technology may help mitigate these limitations and improve dietary data capture.Objective: Our objective was to evaluate the accuracy of a novel mobile application (PIQNIQ) in capturing dietary intake by self-report. Our secondary objective was to assess whether food capture using PIQNIQ was comparable with an interviewer-assisted 24-h recall (24HR).Methods: This study was a single-center randomized clinical trial enrolling 132 adults aged 18 to 65 y from the general population. Under a provided-food protocol with 3 menus designed to include a variety of foods, participants were randomly assigned to 1 of 3 food capture methods: simultaneous entry using PIQNIQ, photo-assisted recall using PIQNIQ, and 24HR. Primary outcomes were energy and nutrient content (calories, total fat, carbohydrates, protein, added sugars, calcium, dietary fiber, folate, iron, magnesium, potassium, saturated fat, sodium, and vitamins A, C, D, and E) captured by the 3 methods.Results: The majority of nutrients reported were within 30% of consumed intake in all 3 food capture methods (n = 129 completers). Reported intake was highly (>30%) overestimated for added sugars in both PIQNIQ groups and underestimated for calcium in the photo-assisted recall group only (P < 0.001 for all). However, in general, both PIQNIQ methods had similar levels of accuracy and were comparable to the 24HR except in their overestimation (>30%) of added sugars and total fat (P < 0.001 for both).Conclusions: Our results suggest that intuitive, technology-based methods of dietary data capture are well suited to modern users and, with proper execution, can provide data that are comparable to data obtained with traditional methods. This trial was registered at clinicaltrials.gov as NCT03578458. [ABSTRACT FROM AUTHOR]

Background: Pearl millet is the chief source of energy in the diet in some developing regions, but has a limited amount of indispensable amino acid lysine. Complementation with pulses like lentils can improve the protein quality of millet diets, but the knowledge of lysine bioavailability (BA) in millet and lentils is lacking.Objectives: The study objectives were to determine the BA of lysine in millet and lentils separately and to assess the effect of complementation of millet and lentils in a mixed meal format.Methods: We studied 9 healthy young men (≤30 y; BMI <25) in a repeated-measure design using the indicator amino acid oxidation (IAAO) method, with L-[1-13C] phenylalanine as the indicator. Each subject completed 7 or 8 experiments in random order. On the reference diet, subjects received 4 graded levels of L-lysine (5, 8, 12, and 15 mg·kg-1.d-1) from a crystalline amino acid mixture patterned after egg protein; on the test diets, they received 3 levels of lysine (10, 12, and 15 mg·kg-1.d-1) from either steamed millet or stewed lentils; and on the complementation diet, they received 1 level of lysine from a mixed meal of steamed millet and stewed lentils. The BA of lysine and the effect of complementation were assessed by comparing the IAAO responses to the test diets and the complementation diet with the IAAO response to L-lysine intakes in the reference protein, using the slope ratio method.Results: The BA of lysine was 97% from millet and 80% from lentils. Complementation of steamed millet with stewed lentils decreased the oxidation of L-[1-13C] phenylalanine by 27% (P < 0.05), signifying improved quality of the combined millet and lentil protein.Conclusions: Lysine has high BA but is still limiting in steamed pearl millet. Complementation with lentils in a 2:1 ratio is recommended to meet the lysine and protein requirements for adult men consuming a millet-based diet. This trial was registered at clinicaltrials.gov as NCT03674736 and NCT03339167. [ABSTRACT FROM AUTHOR]

Population-based studies report differences in folate status indicators among Mexican American (MA), African American (AA) and Caucasian (CA) women. It is unclear, however, whether these differences are due to variations in dietary folate intake. The present study was designed to investigate the influence of ethnicity/race on folate status parameters in MA, AA, and CA women (18-45 y; n = 14 in each group) under conditions of strictly controlled folate intake. In addition, the adequacy of the 1998 folate U.S. recommended dietary allowance (RDA), 400 micro g/d as dietary folate equivalents (DFE), for non-Caucasian women was assessed. Subjects (n = 42) with the methylenetetrahydrofolate reductase 677 CC genotype consumed a low-folate diet (135 micro g DFE/d) for 7 wk followed by repletion with 400 (7 MA, 7 AA, 7 CA) or 800 micro g DFE/d (7 MA, 7 AA, 7 CA) for 7 wk. AA women had lower (P

The purpose of this study was to determine a cut-off value of the molar ratio of retinol-binding protein to transthyretin (RBP:TTR) to indicate marginal vitamin A (VA) deficiency. Plasma RBP and TTR were measured by radial immunodiffusion in two groups of patients, i.e., surgical patients with known hepatic VA stores, and a cohort of children residing in a malaria-endemic area of Papua New Guinea who had received placebo or 210 micro mol of VA every 3 mo for 9 mo. A RBP:TTR ratio < or =0.36 selectively detected five of seven patients (71% sensitivity) with hepatic VA stores < or =69.9 nmol/g of tissue (i.e., < or =20 micro g/g), indicative of marginal VA deficiency. Using this cut-off value, 28% (n = 245) of children from Papua New Guinea had marginal VA deficiency before supplementation. After 7 mo, a low ratio persisted in 29% (n = 92) of placebo-treated children but in only 11% (n = 83) of those receiving VA supplements (chi(2), P < 0.01). At the end of the study, 13 mo after initiation or 4 mo after the last dose of VA, the percentage of children with a low ratio was still lower (chi(2), P < 0.02) in the VA group, 42.5% (n = 113) than in the placebo group, 58.6% (n = 118). These results demonstrate that a cut-off value < or =0.36 is indicative of marginal VA deficiency and can be used as an indirect method of VA assessment. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (ARMD) is inversely associated with the accumulation of lutein + zeaxanthin in the macula, but higher lutein intakes are inconsistently related to reduced risk of ARMD in epidemiologic studies. Resolution of efficacy awaits clinical trials designed with knowledge of lutein supplement pharmacokinetics. Lutein bioavailability was determined for lutein diester and unesterified lutein formulations as they might be incorporated into dietary supplements. Healthy subjects (n = 18) consumed a single dose of each formulation (either 0.5 or 0.67 micro mol lutein/kg body, 10 and 8 subjects, respectively) in random order, and the appearance of free lutein + zeaxanthin was measured in serum from 0 to 408 h. Areas under the serum concentration x time curves (AUC), as a measure of bioavailability, were independent of gender, body mass index and lutein dose. The lutein diester formulation was 61.6% more bioavailable than the unesterified lutein formulation with higher mean AUC, maximum serum concentration and ascending slope (P < 0.05). The AUC was greater in 14 of 18 subjects when they consumed the lutein diester formulation. Comparison with data from previous studies suggested that dissolution was a greater limitation to bioavailability than lutein ester hydrolysis because an oil-solubilized unesterified lutein preparation, given at 0.5 micro mol/kg body, resulted in greater mean peak concentrations and AUC compared with either the unesterified or lutein diester formulations used in our study. In conclusion, the lutein diester formulation poses no impediment to lutein bioavailability at the doses tested, but formulation dissolution is an important factor in lutein bioavailability and should be evaluated before a supplement and dose are selected for use in clinical trials. [ABSTRACT FROM AUTHOR]

Oral exposure to dietary fat (through modified sham feeding, which entails mastication and expectoration of foods) augments the postprandial triacylglycerol (TAG) concentration, in part, though augmented lipid absorption. This study was designed to characterize early events in this process. At 2200 h, 25 healthy adults (13 men, 12 women) consumed 80 g of almonds (high oleic acid content) and fasted until approximately 0700 h. After placement of a catheter in a hand vein and 4 blood draws at 10-min intervals, 50 1-g safflower oil (high linoleic acid content) capsules were consumed. After another blood draw, modified sham feeding was initiated with a cracker only or cracker with cream cheese in random order with 1 wk between trials. Oral exposures occurred at 5-min intervals for 60 min then at 15-min intervals from min 60 to 120. Additional blood draws occurred at 2, 4, 6, 8, 10, 12, 14, 30, 60, 120, 240, 360 and 480 min. Oral stimulation, especially by fat, prompted the rapid (mean approximately 23 min) release of lipid stored from the previous meal (almonds) in all participants. This resulted in multimodal postprandial triacylglycerol (TAG) peaks generally occurring at 0-30 min, 60-120 min and 240-480 min after loading and initiation of oral stimulation. TAG magnitudes during these times were correlated (r = 0.40-0.89, P < 0.001-P = 0.053). It is proposed that the sensory-enhanced release of lipid from the residual pool initiates an early TAG rise, which augments the peak attributable to absorption of meal lipid; this in turn supplements a later peak associated with release of endogenously synthesized TAG because lipid from all three sources competed for a common clearance mechanism. If substantiated, additional understanding of the behavioral factors (e.g., eating patterns) that initiate this cascade will be warranted. [ABSTRACT FROM AUTHOR]

The goal of this study was to investigate the effect of the dietary fat composition on LDL peak particle diameter. Therefore, we measured LDL size by gradient gel electrophoresis in 56 (30 men, 26 women) healthy participants in a controlled dietary study. First, all participants received a baseline diet rich in saturated fat for 2 wk; they were then randomly assigned to one of three dietary treatments, which contained refined olive oil [rich in monounsaturated fatty acids (MUFA), n = 18], rapeseed oil [rich in MUFA and (n-3)-polyunsaturated fatty acids (PUFA), n = 18], or sunflower oil [rich in (n-6)-PUFA, n = 20] as the principal source of fat for 4 wk. Repeated-measures ANOVA revealed a small, but significant reduction in LDL size during the oil diet phase (-0.36 nm, P = 0.012), which did not differ significantly among the three groups (P = 0.384). Furthermore, affiliation with one of the three diet groups did not contribute significantly to the observed variation in LDL size (P = 0.690). In conclusion, our data indicate that dietary unsaturated fat similarly reduces LDL size relative to saturated fat. However, the small magnitude of this reduction also suggests that the composition of dietary fat is not a major factor affecting LDL size. [ABSTRACT FROM AUTHOR]

Epidemiologic and clinical studies have shown that nut consumption is associated with favorable plasma lipid profiles and reduced cardiovascular risk. These effects may result from their high monounsaturated fat (MUFA) content but nuts contain constituents other than fatty acids that might be cardioprotective. We conducted a study to compare the effects of whole-almond vs. almond oil consumption on plasma lipids and LDL oxidation in healthy men and women. Using a randomized crossover trial design, 22 normolipemic men and women replaced half of their habitual fat (approximately 14% of approximately 29% energy) with either whole almonds (WA) or almond oil (AO) for 6-wk periods. Compliance was ascertained by monitoring dietary intake via biweekly 5-d food records, return of empty almond product packages and weekly meetings with a registered dietitian. Fat replacement with either WA and AO resulted in a 54% increase in percentage of energy as MUFA with declines in both saturated fat and cholesterol intake and no significant changes in total energy, total or polyunsaturated fat intake. The effects of WA and AO on plasma lipids did not differ compared with baseline; plasma triglyceride, total and LDL cholesterol significantly decreased, 14, 4 and 6% respectively, whereas HDL cholesterol increased 6%. Neither treatment affected in vitro LDL oxidizability. We conclude that WA and AO do not differ in their beneficial effects on the plasma lipid variables measured and that this suggests that the favorable effect of almonds is mediated by components in the oil fraction of these nuts. [ABSTRACT FROM AUTHOR]

Soybean isoflavones have been proposed to be anticarcinogenic, but their effective doses have not been established. To study their bioavailability, seven women consumed 3.4, 6.9, or 10.3 mumol isoflavones/kg body wt in soymilk in each of three meals of a liquid diet on one of three feeding days that were separated by 2-wk washout periods. Subjects were randomly assigned to doses in a cross-over design. Plasma, urine and fecal isoflavones were measured by reverse phase HPLC. In two subjects, fecal isoflavone recovery was 10-20 times that in the other five subjects. Average 48-h urinary recoveries of ingested daidzein and genistein were 16 +/- 4 and 10 +/- 4%, respectively, at all three doses among the five subjects excreting only small amounts of isoflavones in feces, whereas urinary recoveries of daidzein and genistein in the two subjects who excreted large amounts of fecal isoflavones were 32 +/- 5 and 37 +/- 6%, respectively. Urinary isoflavone excretion was nearly zero in all subjects at 48 h after dosing. Average plasma concentration of genistein at 24 h after the breakfast isoflavone dose in subjects excreting large amounts of fecal isoflavones was significantly greater by 2.5-fold than in subjects who excreted small amounts of fecal isoflavones (P < 0.05). In vitro anaerobic incubation of isoflavones with human feces showed that intestinal half-life of daidzein and genistein may be as little as 7.5 and 3.3 h, respectively. These data suggest that human isoflavone bioavailability depends upon the relative ability of gut microflora to degrade these compounds. [ABSTRACT FROM AUTHOR]

We evaluated the ability of a biological marker (nitrogen excretion expressed as protein) to accurately reflect the protein intake of 12 healthy subjects consuming a low protein diet (0.6 g protein/kg standard body wt). In this crossover study, protein intake was confirmed by chemically analyzing a duplicate of the constant diet each subject consumed for 3 d and by calculating protein content of self-selected diets recorded during two additional 3-d periods. Diet analysis matched excretion (difference 0.03 +/- 0.04 g protein/kg standard body wt, means +/- SEM). Self-selected intake manually calculated by subjects using educational materials matched the prescription [0.60 (0.42, 0.86) g protein/kg standard body wt, median (range)], but underestimated excretion by 0.18 +/- 0.02 g protein/kg standard body wt (means +/- SEM). Self-selected intake recalculated by the authors using a computerized database was only +0.05 (-0.08, +0.44) g protein/kg standard body wt higher than subjects' calculations, suggesting that discrepancies between databases and/or subject calculation errors only partially accounted for how greatly self-selected intake underestimated excretion. In a secondary analysis of self-selected intake, the three dietitian subjects consumed more energy and excreted less protein than nondietitians (137 +/- 4.9 vs. 94 +/- 3.5 kJ/standard body wt; 0.72 +/- 0.02 vs. 0.83 +/- 0.02 g protein/kg standard body wt), suggesting that adequate energy intake and/or additional training might improve agreement between intake and excretion. Thus, discrepancies between protein excretion and reported intake may reflect factors other than willful noncompliance. [ABSTRACT FROM AUTHOR]