The Journal of nutrition
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The Journal of nutrition · May 2013
Randomized Controlled Trial Comparative StudyIntake of whole-grain and fiber-rich rye bread versus refined wheat bread does not differentiate intestinal microbiota composition in Finnish adults with metabolic syndrome.
Whole-grain (WG) foods rich in indigestible carbohydrates are thought to modulate the composition of the intestinal microbiota. We investigated in a randomized, parallel, 2-arm 12-wk intervention whether consumption of WG and fiber-rich rye breads compared with refined wheat breads affected the microbiota composition in Finnish individuals aged 60 ± 6 y with metabolic syndrome. Fecal samples from 51 participants (25 males, 26 females) before and after the intervention were processed for the microbiota analysis using a phylogenetic microarray and quantitative polymerase chain reactions targeting the 16S rRNA gene. ⋯ In this group, the abundance of bacteria related to Bacteroides vulgatus, B. plebeius, and Prevotella tannerae decreased, whereas that of bacteria related to Collinsella and members of the Clostridium clusters IV and XI increased. In a multivariate regression analysis, the abundance of Bacteroides spp. was best explained by different fat compounds among dietary variables, whereas the main sugar-converting butyrate-producers were mostly associated with the intake of whole- and refined-grain bread and fiber. Our results indicate that the quality of grains has a minor effect on the intestinal microbiota composition in participants with metabolic syndrome and suggest that the dietary influence on the microbiota involves other dietary components such as fat.
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The Journal of nutrition · Jul 2012
Randomized Controlled Trial Comparative StudyFortified malted milk drinks containing low-dose ergocalciferol and cholecalciferol do not differ in their capacity to raise serum 25-hydroxyvitamin D concentrations in healthy men and women not exposed to UV-B.
Uncertainty remains regarding the efficacy of low intakes of ergocalciferol (vitamin D2 or D2) and cholecalciferol (vitamin D3 or D3) provided in food to increase serum 25-hydroxy-vitamin D (25-OH-D) metabolite concentrations when UV-B exposure is low. We recruited 40 healthy men and women into a double-blind, parallel design, randomized controlled trial. Participants received placebo or 1 of 4 experimental treatments (D2 or D3 at 5 or 10 μg/d) supplied as a malted milk drink for 4 wk during a period of minimal UV-B exposure in the UK. ⋯ Increments from baseline compared with the placebo group following 5 and 10 μg/d of D2 were (mean ± SEM) 9.4 ± 2.5 and 17.8 ± 2.4 nmol/L for 25-OH-D2 and following 5 and 10 μg/d of D3 were 15.1 ± 4.7 and 22.9 ± 4.6 nmol/L for 25-OH-D3, respectively. There was no difference between D2 and D3 groups in the incremental AUC of their respective metabolites. These findings suggest that D2 and D3 are equipotent in increasing 25-OH-D in healthy men and women with negligible UV-B exposure.
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The Journal of nutrition · May 2012
Randomized Controlled TrialMultiple micronutrient-fortified rice affects physical performance and plasma vitamin B-12 and homocysteine concentrations of Indian school children.
Fortifying rice with multiple micronutrients could be a promising strategy for combat micronutrient deficiencies in developing countries. We determined the efficacy of extruded rice grains fortified with multiple micronutrients on the prevalence of anemia, micronutrient status, and physical and cognitive performance in 6- to 12-y-old, low-income school children in Bangalore, India. In a randomized, double-blind, controlled trial, 258 children were assigned to 1 of 3 intervention groups to receive rice-based lunch meals fortified with multiple micronutrients with either low-iron (6.25 mg) or high-iron (12.5 mg) concentrations or identical meals with unfortified rice. ⋯ After 6 mo, plasma vitamin B-12 and homocysteine concentrations (both P < 0.001) as well as physical performance (P < 0.05) significantly improved in the intervention arms. No between-group differences were observed in hemoglobin concentration, anemia, and deficiencies of other micronutrients or cognitive function after 6 mo, but paired analyses revealed a small reduction in anemia prevalence in children in the low-iron group. The fortified rice was efficacious in improving vitamin B-12 status and physical performance in Indian school children.
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The Journal of nutrition · Apr 2012
Randomized Controlled Trial Comparative StudyWhole grain compared with refined wheat decreases the percentage of body fat following a 12-week, energy-restricted dietary intervention in postmenopausal women.
Observational studies show inverse associations between intake of whole grain and adiposity and cardiovascular risk; however, only a few dietary intervention trials have investigated the effect of whole-grain consumption on health outcomes. We studied the effect of replacing refined wheat (RW) with whole-grain wheat (WW) for 12 wk on body weight and composition after a 2-wk run-in period of consumption of RW-containing food intake. In this open-label randomized trial, 79 overweight or obese postmenopausal women were randomized to an energy-restricted diet (deficit of ~1250 kJ/d) with RW or WW foods providing 2 MJ/d. ⋯ Serum total and LDL cholesterol increased by ~5% (P < 0.01) in the RW group but did not change in the WW group; hence, the changes differed between the groups (P = 0.02). In conclusion, consumption of whole-grain products resulted in a greater reduction in the percentage fat mass, whereas body weight changes did not differ between the RW and WW groups. Serum total and LDL cholesterol, two important risk factors of cardiovascular disease, increased with RW but not WW consumption, which may suggest a cardioprotective role for whole grain.
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The Journal of nutrition · Oct 2011
Randomized Controlled Trial Comparative StudyLow maternal vitamin B-12 status is associated with offspring insulin resistance regardless of antenatal micronutrient supplementation in rural Nepal.
Questions have been raised about potentially negative effects of antenatal folic acid use in populations with a high prevalence of vitamin B-12 deficiency. Our objective was to examine the association between maternal folate and vitamin B-12 status in pregnancy on offspring insulin resistance and examine whether the effects of maternal micronutrient supplementation varied by baseline maternal folate and/or vitamin B-12 status. Pregnant women were cluster randomized to receive daily supplements containing vitamin A alone or with folic acid, folic acid+iron, folic acid+iron+zinc, or a multiple micronutrient. ⋯ Children whose mothers were deficient in vitamin B-12 (<148 pmol/L, 27%) during early pregnancy had a 26.7% increase in HOMA-IR (P = 0.02), but there was no association with maternal folate status. Among children born to women who were vitamin B-12 deficient at baseline, the percent difference in HOMA-IR compared to the control group was 15.1% (95% CI: -35.9, 106.4), 4.9% (-41.6, 88.5), 3.3% (-38.4, 73.5), and 18.1% (-29.0, 96.7) in the folic acid, folic acid-iron, folic acid-iron-zinc, and multiple micronutrient supplementation groups, respectively, none of which were significant. Maternal vitamin B-12 deficiency is associated with an elevated risk of insulin resistance, but supplementation with folic acid or other micronutrients led to no significant change in insulin resistance in school-aged offspring.