On the effect of flavonoids and dietary fibre in lingonberries on atherosclerotic plaques, lipid profiles and gut microbiota composition in Apoe-/- mice.

It has not been clarified whether the anti-atherosclerotic effect of lingonberry can be ascribed to its content of flavonoids or dietary fibre or both. The aim of this study was to evaluate the metabolic effects of whole lingonberries compared with isolated flavonoid and fibre fractions on atherosclerotic plaques, plasma lipid profiles, gut microbiota and microbiota-dependent metabolites in an Apoe-/- mouse model. Mice fed whole lingonberries showed the lowest amount of atherosclerotic plaques, while mice fed the fibre fraction had the highest formation of caecal butyric acid. Flavonoids, rather than dietary fibre, were suggested to be the components that favour proliferation of Akkermansia, as judged by the lowest abundance of this bacterium in mice fed the fibre fraction. All groups fed lingonberry diets had both, lower Firmicutes/Bacteroidetes ratios and creatinine concentrations, compared with the control. To conclude, different components in lingonberries are associated with different physiological effects in Apoe-/- mice.

Effects of Whole Brown Bean and Its Isolated Fiber Fraction on Plasma Lipid Profile, Atherosclerosis, Gut Microbiota, and Microbiota-Dependent Metabolites in Apoe-/- Mice.

The health benefits of bean consumption are widely recognized and are largely attributed to the dietary fiber content. This study investigated and compared the effects of whole brown beans and an isolated bean dietary fiber fraction on the plasma lipid profile, atherosclerotic plaque amount, gut microbiota, and microbiota-dependent metabolites (cecal short-chain fatty acids (SCFAs) and plasma methylamines) in Apoe-/- mice fed high fat diets for 10.5 weeks. The results showed that both whole bean and the isolated fiber fraction had a tendency to lower atherosclerotic plaque amount, but not plasma lipid concentration. The whole bean diet led to a significantly higher diversity of gut microbiota compared with the high fat diet. Both bean diets resulted in a lower Firmicutes/Bacteroidetes ratio, higher relative abundance of unclassified S24-7, Prevotella, Bifidobacterium, and unclassified Clostridiales, and lower abundance of Lactobacillus. Both bean diets resulted in higher formation of all cecal SCFAs (higher proportion of propionic acid and lower proportion of acetic acid) and higher plasma trimethylamine N-oxide concentrations compared with the high fat diet. Whole beans and the isolated fiber fraction exerted similar positive effects on atherosclerotic plaque amount, gut microbiota, and cecal SCFAs in Apoe-/- mice compared with the control diets.

The Application of Pulse Flours in the Development of Plant-Based Cheese Analogues: Proximate Composition, Color, and Texture Properties.

Despite the many benefits of pulses, their consumption is still very low in many Western countries. One approach to solving this issue is to develop attractive pulse-based foods, e.g., plant-based cheeses. This study aimed to assess the suitability of different types of pulse flour, from boiled and roasted yellow peas and faba beans, to develop plant-based cheese analogues. Different stabilizer combinations (kappa- and iota-carrageenan, kappa-carrageenan, and xanthan gum) were tested. The results showed that firm and sliceable pulse-based cheese analogues could be prepared using all types of pulse flour using a flour-to-water ratio of 1:4 with the addition of 1% (w/w) kappa-carrageenan. The hardness levels of the developed pulse-based cheese analogues were higher (1883-2903 g, p < 0.01) than the reference Gouda cheese (1636 g) but lower than the commercial vegan cheese analogue (5787 g, p < 0.01). Furthermore, the crude protein (4-6% wb) and total dietary fiber (6-8% wb) contents in the developed pulse-based cheese analogues were significantly (p < 0.01) higher than in the commercial vegan cheese analogue, whereas the fat contents were lower. In conclusion, flours from boiled and roasted yellow peas and faba beans have been shown to be suitable as raw materials for developing cheese analogues with nutritional benefits.

Simultaneous quantification of trimethylamine N-oxide, trimethylamine, choline, betaine, creatinine, and propionyl-, acetyl-, and L-carnitine in clinical and food samples using HILIC-LC-MS.

Trimethylamine-N-oxide (TMAO), a microbiome-derived metabolite from the metabolism of choline, betaine, and carnitines, is associated to adverse cardiovascular outcomes. A method suitable for routine quantification of TMAO and its precursors (trimethylamine (TMA), choline, betaine, creatinine, and propionyl-, acetyl-, and L-carnitine) in clinical and food samples has been developed based on LC-MS. TMA was successfully derivatized using iodoacetonitrile, and no cross-reactions with TMAO or the other methylamines were detected. Extraction from clinical samples (plasma and urine) was performed after protein precipitation using acetonitrile:methanol. For food samples (meatballs and eggs), water extraction was shown to be sufficient, but acid hydrolysis was required to release bound choline before extraction. Baseline separation of the methylamines was achieved using a neutral HILIC column and a mobile phase consisting of 25 mmol/L ammonium formate in water:ACN (30:70). Quantification was performed by MS using external calibration and isotopic labelled internal standards. The assay proved suitable for both clinical and food samples and was linear from ≈ 0.1 up to 200 µmol/L for all methylamines except for TMA and TMAO, which were linear up to 100 µmol/L. Recoveries were 91-107% in clinical samples and 76-98% in food samples. The interday (n=8, four duplicate analysis) CVs were below 9% for all metabolites in clinical and food samples. The method was applied successfully to determine the methylamine concentrations in plasma and urine from the subjects participating in an intervention trial (n=10) to determine the effect of animal food ingestion on methylamine concentrations.

High-Moisture Meat Analogues Produced from Yellow Pea and Faba Bean Protein Isolates/Concentrate: Effect of Raw Material Composition and Extrusion Parameters on Texture Properties.

Yellow pea and faba bean are potential candidates to replace soybean-based ingredients due to their suitability for cultivation in the northern hemisphere, non-genetically modified organisms cultivation practice and low risk of allergenicity. This study examined the functionality of local yellow pea and faba bean protein isolates/concentrate as meat analogue products. The most critical factors affecting the texture properties of meat analogue were also determined. Extrusion was used to produce high-moisture meat analogues (HMMAs) from yellow pea and faba bean protein isolates/concentrates and HMMAs with fibrous layered structures was successfully produced from both imported commercial and local sources. The texture properties of the HMMA produced were mainly affected by the ash, fiber and protein content and water-holding capacity of the source protein. Three extrusion process parameters (target moisture content, extrusion temperature, screw speed), also significantly affected HMMA texture. In conclusion, functional HMMA can be produced using protein isolates derived from locally grown pulses.

Bread making with sourdough and intact cereal and legume grains - effect on glycaemic index and glycaemic load.

The concept of glycaemic index (GI) has led to efforts to develop low-GI foods. Bread contributes around one-quarter of carbohydrate intake in the Swedish diet. In this study, we sought to develop low-GI bread prototypes and examined the effects of bread making on content of total dietary fibre (TDF) and resistant starch (RS). Five bread prototypes were made in a commercial bakery, using sourdough fermentation and intact cereal and legume kernels. Predicted (p-GI) and in vivo GI values were determined, and TDF and RS were quantified. The p-GI value of the five prototypes was between 56 and 68. The confirmed in vivo GI value was 65 and 67 for two of the breads. The TDF content (≥17%) was not affected by bread making, but RS content was increased by three-fold. All breads were categorised as medium-GI, but with low glycaemic load (GL).

Diet and nutrient status of legume consumers in Sweden: a descriptive cross-sectional study.

BACKGROUND: Legumes are nutrient-dense foods and can be an environmentally sustainable alternative to meat consumption. Data on legume intake are scarce and data on legume consumption in Sweden are lacking. This study investigated dietary intake and dietary patterns, together with iron, vitamin D, and folate status, in relation to legume consumption in Sweden. METHODS: Cross-sectional dietary and biomarker data (n 1760) from the 2011 Riksmaten national survey were analyzed. All legume foods (including soy) were identified from 4-day dietary records and ferritin, folate, and vitamin D status in a subgroup (n 280). Participants were classified into non-consumers and quartiles of legume intake. Principal Component Analysis (PCA) was performed to uncover dietary patterns associated with legume intake. Partial Least Square (PLS) regression was used to identify variables associated with variations in legume consumption. RESULTS: Legumes were consumed by 44% of the population, with mean (SD) intake of 138 (84) g/d in the highest and 11 (5) g/d in the lowest quartiles. Among consumers, 6% reported being vegetarian, compared with 0.9% among non-consumers. Legume consumers drank less alcohol, but had higher intakes of energy, dietary fiber, folate, thiamin, and several minerals, and more often met recommended intake levels for folate and fiber, critical nutrients in Sweden. Biomarker status did not differ with legume intake. PCA revealed multiple loadings on legumes that generally reflected healthier eating habits for legume-consuming women. PLS revealed that vegetarianism was most influential for high legume intake. Other influential variables were high fruit, tea, nut, and seed intakes. High intake of meat, sodas, fast foods, and sweet foods, together with omnivorism, were influential for low legume intake. The associations were similar for men and women. CONCLUSIONS: This study supports dietary recommendations on inclusion of legumes in a healthy diet. Greater focus on assessment of legume intake is necessary to explore the population-wide health effects of legumes as sustainable meat alternatives, and to reinforce national nutritional guidelines.

Characterization of Flavonoid Compounds in Common Swedish Berry Species.

Berries are considered an ideal source of polyphenols, especially from the flavonoid group. In this study, we examined the flavonoid content in 16 varieties of Swedish lingonberry, raspberry, blueberry, and strawberry. Nineteen flavonoids were simultaneously quantified using external standards. An additional 29 flavonoids were tentatively identified using MS as no standards were available. Quantification was done using HPLC-UV after optimization of chromatographic and extraction procedures. The method showed high linearity within the range of 2-100 µg/mL (correlation co-efficient >0.999), intra- and inter-day precision of 1.7-7.3% and average recovery above 84% for all compounds. Blueberries and lingonberries were found to contain higher contents of flavonoids (1100 mg/100 g dry weight) than raspberries and strawberries (500 mg/100 g dry weight). Anthocyanins were the dominant flavonoids in all berries. The tentatively characterized compounds contribute 18%, 29%, 61%, and 67% of the total flavonoid content in strawberries, lingonberries, raspberries, and blueberries, respectively. Overall, Swedish berries were shown to be good sources of polyphenols.

Glucose Appearance Rate Rather than the Blood Glucose Concentrations Explains Differences in Postprandial Insulin Responses between Wholemeal Rye and Refined Wheat Breads-Results from A Cross-Over Meal Study.

SCOPE: Ingestion of rye bread leads to lower postprandial plasma insulin concentrations than wheat bread ingestion, but most often not too different glucose profiles. The mechanism behind this discrepancy is still largely unknown. This study investigates whether glucose kinetics may explain the observed discrepancy. METHODS AND RESULTS: Nine healthy men participated in a crossover study, eating 50 g of available carbohydrates as either refined wheat (WB) or traditional wholemeal rye bread (WMR) during d-[6,6-2 H2 ]glucose infusion. Labeled glucose enrichment is measured by an HPLC-TOF-MS method. The calculated rate of glucose appearance (RaE) is significantly lower after ingestion of WMR during the initial 15 min postprandial period. Additionally, the 0-90 min RaE area under the curve (AUC) is significantly lower after ingestion of WMR, as is plasma gastric inhibitory polypeptide (GIP) at 60 and 90 min. Postprandial glycemic responses do not differ between the breads. Postprandial insulin is lower after ingestion of WMR at 45 and 60 min, as is the 0-90 min AUC. CONCLUSION: Ingestion of WMR elicits a lower rate of glucose appearance into the bloodstream compared with WB. This may explain the lower insulin response observed after rye bread ingestion, commonly known as the rye factor.

Flours from Swedish pulses: Effects of treatment on functional properties and nutrient content.

Despite the high nutritional profile in pulses, pulse consumption in Sweden is still low. However, the recent increase in consumption of sustainable and locally produced food in Sweden is driving demand for a versatile, functional pulse-based ingredient that can be incorporated into different food products. This study assessed different treatments (boiling, roasting, and germination) when preparing flour from domestically grown pulses (yellow pea, gray pea, faba bean, and white bean). Functional properties (water and oil absorption capacity, emulsion and foaming properties, and gelation concentration) of the flours produced following different treatments and their nutrient content (total dietary fiber, total choline, and folate content) were determined. Depending on pulse type, all treatments increased (p < .001) water absorption capacity up to threefold and gelation concentration up to twofold, whereas emulsion activity and foaming capacity decreased by 3%-33% and 5%-19%, respectively, compared with flour made from raw pulses. All treatments also had a significant effect (p < .001) on nutrient content. Total dietary fiber increased (p < .02) by 11%-33%, depending on treatment and pulse type. Boiling decreased (p < .001) total choline and folate content in all pulse flours, by 17%-27% and 15%-32%, respectively. Germination doubled folate content (p < .001) in flour from both pea types compared with flour from the raw peas. In conclusion, treated pulse flours could be useful in food applications such as coating batter, dressings, beverages, or bakery goods, to improve the content of fiber, total choline, and folate.

Plasma metabolite profiles in healthy women differ after intervention with supplemental folic acid v. folate-rich foods.

Public health authorities recommend all fertile women to increase their folate intake to 400 µg/d by eating folate-rich foods or by taking a folic acid supplement to protect against neural tube defects. In a previous study it was shown that folate-rich foods improved folate blood status as effectively as folic acid supplementation. The aim of the present study was to investigate, using NMR metabolomics, the effects of an intervention with a synthetic folic acid supplement v. native food folate on the profile of plasma metabolites. Healthy women with normal folate status received, in parallel, 500 µg/d synthetic folic acid from a supplement (n 18), 250 µg/d folate from intervention foods (n 19), or no additional folate (0 µg/d) through a portion of apple juice (n 20). The metabolic profile of plasma was measured using 1H-NMR in fasted blood drawn at baseline and after 12 weeks of intervention. Metabolic differences between the groups at baseline and after intervention were assessed using a univariate statistical approach (P ≤ 0·001, Bonferroni-adjusted significance level). At baseline, the groups showed no significant differences in measured metabolite concentrations. After intervention, eight metabolites, of which six (glycine, choline, betaine, formate, histidine and threonine) are related to one-carbon metabolism, were identified as discriminative metabolites. The present study suggests that different folate forms (synthetic v. natural) may affect related one-carbon metabolites differently.

Compilation of a standardised international folate database for EPIC.

This paper describes the methodology applied for compiling an "international end-user" folate database. This work benefits from the unique dataset offered by the European Prospective Investigation into Cancer and Nutrition (EPIC) (N=520,000 subjects in 23 centres). Compilation was done in four steps: (1) identify folate-free foods then find folate values for (2) folate-rich foods common across EPIC countries, (3) the remaining "common" foods, and (4) "country-specific" foods. Compiled folate values were concurrently standardised in terms of unit, mode of expression and chemical analysis, using information in national food composition tables (FCT). 43-70% total folate values were documented as measured by microbiological assay. Foods reported in EPIC were either matched directly to FCT foods, treated as recipes or weighted averages. This work has produced the first standardised folate dataset in Europe, which was used to calculate folate intakes in EPIC; a prerequisite to study the relation between folate intake and diseases.

Folate content in faba beans (Vicia faba L.)-effects of cultivar, maturity stage, industrial processing, and bioprocessing.

Faba beans are an important source of folate and commonly consumed in Egypt. This study examined the effects of Egyptian industrial food processing (e.g., canning and freezing), germination, cultivar, and maturity stages on folate content, with the aim to develop a candidate functional canned faba bean food with increased folate content. The folate content in four cultivars of green faba beans ranged from 110 to 130 µg 100 g(-1) fresh weight (535-620 µg 100 g(-1) dry matter [DM]), which was four- to sixfold higher than in dried seeds. Industrial canning of dried seeds resulted in significant folate losses of ∼20% (P = 0.004), while industrial freezing had no effect. Germination of faba beans increased the folate content by >40% (P < 0.0001). A novel industrial canning process involving pregermination of dried faba beans resulted in a net folate content of 194 µg 100 g(-1) DM, which is 52% more than in conventional canned beans. The consumption of green faba beans should be recommended, providing ∼120 µg dietary folate equivalents per 100 g/portion.

Effect of type of heat treatment of breastmilk on folate content and pattern.

BACKGROUND: Breastmilk is the recommended aliment for preterm infants. Milk banks provide donated breastmilk for the neonatal care of preterm infants when mother's own milk is not is available. To avoid pathogen transmission, donated breastmilk is heat-treated according to different procedures before administration. There is varying information on the effect of heat treatment on folate in breastmilk. Sufficient folate intake, however, is essential for normal growth and brain development. This study determined and compared the effects of different heat treatments on breastmilk folate content and pattern of individual folate forms. MATERIALS AND METHODS: Donated Swedish breastmilk samples were heat-treated according to three procedures: two low temperature treatments (57°C, 23 minutes; 62.5°C, 12 minutes) and a rapid high temperature treatment (heating to 73°C in boiling water). The folate content and pattern were determined before and after treatment by high-performance liquid chromatography. RESULTS: The folate content in 38 untreated Swedish breastmilk samples was 150±46 nmol/L. Two different folate vitamers were detected: 5-methyltetrahydrofolate (78±7%) and tetrahydrofolate (22±7%). Heat treatment affected only tetrahydrofolate stability and decreased folate content by 15-24%; however, the effects on folate content did not differ among the investigated heat treatment procedures. CONCLUSIONS: Folate losses during heat treatment of human milk were considered acceptable. Yet, native folate content of heat-treated, non-fortified breastmilk supplied only 25% of the recommended daily intake for preterm infants.

Quantification of isotope-labeled and unlabeled folates and folate catabolites in urine samples by stable isotope dilution assay.

Dual-label stable isotope dilution assays for the simultaneous quantification of isotopologic folates in clinical samples offer the perspective for differentiating between unlabeled folates from endogenous body pools and administered [13C5]-labeled folates from a test dose when performing bioavailability trials. In contrast to intact folates, this methodology could hitherto not be applied to the quantification of the folate catabolites, p-aminobenzoyl glutamate and p-acetamidobenzoyl glutamate. In this study, [2H4]-p-aminobenzoyl glutamate, [2H4]-p-acetamidobenzoyl glutamate, and unlabeled p-acetamidobenzoyl glutamate were synthesized. The synthesis of the [2H4]-labeled compounds started at unlabeled p-aminobenzoic acid. For the formation of p-acetamidobenzoyl glutamate, p-aminobenzoyl glutamate was acetylated. The new substances were applied successfully in stable isotope dilution assays for the simultaneous quantification of the [13C5]-labeled and unlabeled folate catabolites, p-aminobenzoyl glutamate and p-acetamidobenzoyl glutamate, along with the predominant folate vitamers in urine. The assays were based on clean-up by strong anion exchange followed by liquid chromatography-tandem mass spectrometry detection. Assay sensitivity was sufficient to detect the folate catabolites in physiologic concentrations. The limit of detection was below 0.4 and 0.3 nmol/100 g for p-aminobenzoyl glutamate isotopologues and p-acetamidobenzoyl glutamate isotopologues in urine, respectively. The successful synthesis of [2H4]-p-aminobenzoyl glutamate, [2H4]-p-acetamidobenzoyl glutamate, and unlabeled p-acetamidobenzoyl glutamate and the implementation of these substances in stable isotope dilution assays allows dual-label designs that provide a more detailed insight into human folate metabolism.

Enhancement of the folate content in Egyptian pita bread.

INTRODUCTION: Egypt has a high incidence of neural tube defects related to folate deficiency. One major food source for folate is pita (baladi) bread, which is consumed daily. Bioprocessing (e.g. germination) has been reported to increase the folate content in cereals. The aim was to produce pita bread with increased folate content using germinated wheat flour (GWF). METHODS: Prior to milling the effects of germination and drying conditions on folate content in wheat grains were studied. Pita bread was baked from wheat flour substituted with different levels of GWF. The folate content in dough and bread and rheological properties of dough were determined. RESULTS: Germination of wheat grains resulted in, depending on temperature, 3- to 4-fold higher folate content with a maximum of 61 µg/100 g DM (dry matter). The folate content in both flour and bread increased 1.5 to 4-fold depending on the level of flour replacement with GWF. Pita bread baked with 50% sieved GWF was acceptable with respect to colour and layer separation, and had a folate content of 50 µg/100 g DM compared with 30 µg/100 g DM in conventional pita bread (0% GWF). CONCLUSION: Using 50% GWF, pita bread with increased folate content, acceptable for the Egyptian consumer, was produced. Consumption of this bread would increase the average daily folate intake by 75 µg.

Critical evaluation of folate data in European and international databases: recommendations for standardization in international nutritional studies.

SCOPE: The objective was to perform an inventory and critical evaluation of folate data in selected European and international databases. The ultimate aim was to establish guidelines for compiling standardized folate databases for international nutritional studies. METHODS AND RESULTS: An ad hoc questionnaire was prepared to critically compare and evaluate folate data completeness, quantification, terminologies, and documentation of 18 European and international databases, and national fortification regulations. Selected countries participated in the European Prospective Investigation into Nutrition and Cancer project and European Food Information Resource Network (EuroFIR). Folate completeness was generally high. "Total folate" was the most common terminology and microbiological assay was the most frequently reported quantification method. There is a lack of comparability within and between databases due to a lack of value documentation, the use of generic or non-appropriate terminologies, folate value conversions, and/or lack of identification of synthetic folic acid. CONCLUSION: Full value documentation and the use of EuroFIR component identifiers and/or INFOODS tagnames for total folate ("FOL") and synthetic folic acid ("FOLAC"), with the additional use of individual folates, will increase comparability between databases. For now, the standardized microbiological assay for total folate and HPLC for synthetic folic acid are the recommended quantification methods.

Quantification of isotope-labelled and unlabelled folates in plasma, ileostomy and food samples.

New stable isotope dilution assays were developed for the simultaneous quantitation of [(13)C(5)]-labelled and unlabelled 5-methyltetrahydrofolic acid, 5-formyltetrahydrofolic acid, folic acid along with unlabelled tetrahydrofolic acid and 10-formylfolic acid in clinical samples deriving from human bioavailability studies, i.e. plasma, ileostomy samples, and food. The methods were based on clean-up by strong anion exchange followed by LC-MS/MS detection. Deuterated analogues of the folates were applied as the internal standards in the stable isotope dilution assays. Assay sensitivity was sufficient to detect all relevant folates in the respective samples as their limits of detection were below 0.62 nmol/L in plasma and below 0.73 µg/100 g in food or ileostomy samples. Quantification of the [(13)C(5)]-label in clinical samples offers the possibility to differentiate between folate from endogenous body pools and the administered dose when executing bioavailability trials.

Human folate bioavailability.

The vitamin folate is recognized as beneficial health-wise in the prevention of neural tube defects, anemia, cardiovascular diseases, poor cognitive performance, and some forms of cancer. However, suboptimal dietary folate intake has been reported in a number of countries. Several national health authorities have therefore introduced mandatory food fortification with synthetic folic acid, which is considered a convenient fortificant, being cost-efficient in production, more stable than natural food folate, and superior in terms of bioavailability and bioefficacy. Other countries have decided against fortification due to the ambiguous role of synthetic folic acid regarding promotion of subclinical cancers and other adverse health effects. This paper reviews recent studies on folate bioavailability after intervention with folate from food. Our conclusions were that limited folate bioavailability data are available for vegetables, fruits, cereal products, and fortified foods, and that it is difficult to evaluate the bioavailability of food folate or whether intervention with food folate improves folate status. We recommend revising the classical approach of using folic acid as a reference dose for estimating the plasma kinetics and relative bioavailability of food folate.

Folate bioavailability from breads and a meal assessed with a human stable-isotope area under the curve and ileostomy model.

BACKGROUND: Recent data revealed differences in human absorption kinetics and metabolism between food folates and folic acid supplements and fortificant. OBJECTIVE: The objective was to determine folate bioavailability after ingestion of breads or a breakfast meal fortified with either 5-CH(3)-H(4) folate or folic acid by using a stable-isotope area under the curve (AUC) and ileostomy model. DESIGN: In a randomized crossover trial, healthy ileostomists (n = 8) ingested single doses of whole-meal bread that contained ap 450 nmol (200 micro g) of either (6S)-[(13)C(5)]5-CH(3)-H(4) folate or [(13)C(5)]folic acid or a breakfast meal that contained ap 450 nmol (200 micro g) [(13)C(5)]folic acid. We collected blood from the subjects during 12 h postdose for assessment of plasma kinetics. Nonabsorbed folate was assessed from labeled folate contents in stomal effluent 12 and 24 h postdose. RESULTS: The median (range) plasma AUC(0 rarr 12) (AUC from 0 to 12 h after ingested dose) of 66 nmol sdot h/L (34-84 nmol sdot h/L) after ingestion of bread that contained (6S)-[(13)C(5)]5-CH(3)-H(4) folate was significantly greater (P lt 0.001) than that after ingestion of [(13)C(5)]folic acid in fortified bread [28 nmol sdot h/L (15-38 nmol sdot h/L)] and a fortified breakfast meal [26 nmol sdot h/L (15-60 nmol sdot h/L)]. Both labeled doses resulted in increases of plasma [(13)C(5)]5-CH(3)-H(4) folate. However, the kinetic variables C(max) (maximum plasma concentration) and T(max) [time (min) of maximum plasma concentration] varied after ingestion of the different folate forms. The stomal folate content was lt 10% of the ingested dose and did not vary significantly after ingestion of test foods that contained (6S)-[(13)C(5)]5-CH(3)-H(4) folate [median (range): 13 nmol (10-31 nmol)] or [(13)C(5)]folic acid [median (range): 25 nmol (8-42 nmol)] (P = 0.33). CONCLUSIONS: Our data confirm differences in plasma absorption kinetics for reduced folates and synthetic folic acid administered with the test foods. Stomal folate contents indicated almost complete bioavailability of labeled folate from the breads or breakfast meal.