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1.
Int J Vitam Nutr Res ; 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37335576

RESUMO

The mass ratio of urinary 2-hydroxyestrone to 16-α-hydroxyestrone (2:16) is hypothesized as a biomarker of breast cancer risk in premenopausal women, with higher ratios being theoretically protective. Cruciferous vegetable intake has been associated with higher urinary 2:16 in some studies. We investigated whether a whole-food supplement made from dried Brussels sprouts and kale would increase urinary 2:16 in comparison with placebo or cruciferous vegetables in women. This randomized, parallel arm, placebo-controlled, partly blinded study included 78 healthy premenopausal women (38-50 y) with screening urinary 2:16 ≤3.0. Subjects received either six capsules containing 550 mg dried Brussels sprouts and kale per capsule, 40 g daily alternating broccoli or Brussels sprouts, or placebo for eight weeks. Urinary 2:16 and creatinine were measured at baseline, four, and eight weeks. Intent-to-treat repeated measures-ANOVA with multiple imputation (n=100) for missing values identified no treatment effect (P=0.9) or treatment-by-time interaction (P=0.6); however, a significant time effect was noted (P=0.02). Per-protocol analyses including complete cases found no treatment effect (P=1) or treatment-by-time interaction (P=0.6); however, the significant time effect remained (P=0.03). Restricting analysis to subjects with >80% compliance maintained the time effect (P=0.02). Using Pearson correlations, android-pattern and android:gynoid fat were predictive of change (P≤0.05). In conclusion, neither cruciferous supplements nor an added vegetable serving altered urinary 2:16 in premenopausal women with eight weeks treatment. This ratio did vary with time, which is important for designing future trials.

2.
Int J Vitam Nutr Res ; 90(3-4): 257-265, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30806607

RESUMO

In some societies, studies involving blood draws, oral vaccinations, or supplementation are surrounded by myths and disbeliefs. If not clarified, they may affect study implementation and negatively impact the outcome of well-intended studies from inadequate participation. Through participatory action research, this paper suggests how future trials could be enhanced with reference to community mobilization, drawing from the experience of two interventions in Zambian children with nutritionally enhanced, biofortified orange maize conducted by the National Food and Nutrition Commission and Tropical Diseases Research Center (Zambia), and University of Wisconsin-Madison (USA). The preparatory phase included site visits, signing of a Memorandum of Understanding, equipment inventory, hiring staff, and community meetings. Prior results were shared before the second intervention. After Institutional Review Boards' approval of procedures, written informed consent was obtained from caregivers. There was overwhelming community participation attributed to the demystification that the project was run by satanists prior to and during the study. Participation led to excellent compliance with 92.8 and 96.4% of subjects completing the final blood draw in 2010 and 2012, respectively. The results of the trials were successfully shared with the district officials and communities from where the study participants were drawn. The positive response by partners and communities, including information sharing, suggests that community mobilization, with the use of varied methods, is effective for full participation of the target groups in feeding trials and would be the case in similar trials if effectively carried out. Community participation in research studies may result in long-term adoption of biofortified foods.


Assuntos
Alimentos , Zea mays , Criança , Humanos , Estado Nutricional/fisiologia , Zâmbia , Zea mays/química , Zea mays/metabolismo
3.
Am J Clin Nutr ; 100(6): 1541-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25411289

RESUMO

BACKGROUND: Biofortification is a strategy to relieve vitamin A (VA) deficiency. Biofortified maize contains enhanced provitamin A concentrations and has been bioefficacious in animal and small human studies. OBJECTIVE: The study sought to determine changes in total body reserves (TBRs) of vitamin A with consumption of biofortified maize. DESIGN: A randomized, placebo-controlled biofortified maize efficacy trial was conducted in 140 rural Zambian children. The paired (13)C-retinol isotope dilution test, a sensitive biomarker for VA status, was used to measure TBRs before and after a 90-d intervention. Treatments were white maize with placebo oil (VA-), orange maize with placebo (orange), and white maize with VA in oil [400 µg retinol activity equivalents (RAEs) in 214 µL daily] (VA+). RESULTS: In total, 133 children completed the trial and were analyzed for TBRs (n = 44 or 45/group). Change in TBR residuals were not normally distributed (P < 0.0001); median changes (95% CI) were as follows: VA-, 13 (-19, 44) µmol; orange, 84 (21, 146) µmol; and VA+, 98 (24, 171) µmol. Nonparametric analysis showed no statistical difference between VA+ and orange (P = 0.34); both were higher than VA- (P = 0.0034). Median (95% CI) calculated liver reserves at baseline were 1.04 (0.97, 1.12) µmol/g liver, with 59% >1 µmol/g, the subtoxicity cutoff; none were <0.1 µmol/g, the deficiency cutoff. The calculated bioconversion factor was 10.4 µg ß-carotene equivalents/1 µg retinol by using the middle 3 quintiles of change in TBRs from each group. Serum retinol did not change in response to intervention (P = 0.16) but was reduced with elevated C-reactive protein (P = 0.0029) and α-1-acid glycoprotein (P = 0.0023) at baseline. CONCLUSIONS: ß-Carotene from maize was efficacious when consumed as a staple food in this population and could avoid the potential for hypervitaminosis A that was observed with the use of preformed VA from supplementation and fortification. Use of more sensitive methods other than serum retinol alone, such as isotope dilution, is required to accurately assess VA status, evaluate interventions, and investigate the interaction of VA status and infection. This trial was registered at clinicaltrials.gov as NCT01814891.


Assuntos
Alimentos Fortificados/análise , Fígado/efeitos dos fármacos , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/epidemiologia , Vitamina A/administração & dosagem , Zea mays/química , Proteína C-Reativa/metabolismo , Criança , Dieta , Feminino , Humanos , Fígado/metabolismo , Masculino , Vitamina A/sangue , Deficiência de Vitamina A/dietoterapia , Zâmbia/epidemiologia , beta Caroteno/administração & dosagem
4.
Food Nutr Bull ; 35(1): 60-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24791580

RESUMO

BACKGROUND: Many programs aim to alleviate vitamin A deficiency. Biofortification is an approach to improve provitamin A carotenoid concentrations of staple crops in some developing countries. In rural Zambia, maize accounts for the majority of energy intake. Provitamin A-biofortified (orange) maize has been released in Zambia. OBJECTIVE: This study quantified food intake of Zambian children from records collected in a feeding trial in 2012 in order to compare adoption of orange maize and a new vegetable (green beans) with white maize and traditional foods. METHODS: One hundred thirty-six children with a mean age of 71.5 +/- 6.9 months were fed three meals a day for 6 days a week for 15 weeks at four feeding centers. Breakfast consisted of maize porridge, and lunch and dinner were stiff porridge (nshima) with various side dishes (relishes). There were three treatment groups, which received orange maize and placebo oil, white maize and placebo oil, or white maize and a daily vitamin A supplement. Food was weighed before and after consumption. Nutritionists were trained to interview the children's caregivers about the previous day's intake using dietary recalls. Nine dietary recalls for each child were recorded and analyzed. RESULTS: Total food intake did not differ among the groups (p = .31) and energy intakes on Sundays (< or = 880 kcal) were below recommendations. Nshima intake was lower in the orange-maize group (p = .008), largely due to a genotype effect. Intakes of relish, green bean, and porridge did not differ among the groups (p > .19). Dietary recalls revealed that children living in sites closer to the main road consumed more on Sundays than children living about 8 km from the main road, but less in the evenings when children were off site. CONCLUSIONS: The intakes of energy of these Zambian children were low. Implementation and adoption of new and biofortified foods is possible with promotion.


Assuntos
Dieta/métodos , Dieta/estatística & dados numéricos , Ingestão de Energia/fisiologia , Alimentos/estatística & dados numéricos , Análise de Variância , Pré-Escolar , Registros de Dieta , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Alimentos Fortificados/estatística & dados numéricos , Humanos , Masculino , Refeições/fisiologia , População Rural/estatística & dados numéricos , Verduras , Deficiência de Vitamina A/prevenção & controle , Zâmbia , Zea mays
5.
J Nutr ; 144(6): 972-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24717369

RESUMO

The acute phase response (APR) to infection can alter blood-based indicators of micronutrient status. Data from a 3-mo randomized, controlled feeding trial in rural Zambian children (n = 181, aged 3-5 y) were used to determine the impact of the APR on indicators of vitamin A and iron status using baseline and final blood samples. Concentrations of acute phase proteins were categorized as raised C-reactive protein (CRP; >5 and >10 mg/L) only, both raised CRP and α1-acid glycoprotein (AGP; >1.2 g/L), raised AGP only, and neither CRP nor AGP raised to identify the respective stages of infection: incubation, early convalescence, convalescence, and healthy state. Data were insufficient to examine the incubation stage of infection. A CRP concentration of >5 mg/L was an effective elevation cutoff point in this population to show impact on micronutrient markers. Time did not affect hemoglobin, serum ferritin, or serum retinol concentrations (P > 0.05). During early convalescence, hemoglobin decreased (14-16%; P ≤ 0.05), serum ferritin increased (279-356%; P ≤ 0.05), and serum retinol decreased (20-30%; P ≤ 0.05). Serum retinol concentrations did not change during convalescence; however, hemoglobin remained depressed (4-9%) and serum ferritin was elevated (67-132%) (both P ≤ 0.05). Modified relative dose response values were unaffected by the APR (P > 0.05) but increased between time points (16%; P ≤ 0.05), indicating a decrease in liver vitamin A reserves on the background of a semiannual vitamin A supplementation program. The observed prevalence of anemia and vitamin A deficiency assessed by serum retinol concentration was higher during the APR (P ≤ 0.05). It is important to consider the impact of infection on dietary interventions and to adjust for acute phase proteins when assessing iron status or vitamin A status by serum retinol concentration alone in children.


Assuntos
Reação de Fase Aguda/sangue , Ferro da Dieta/sangue , Micronutrientes/sangue , Vitamina A/sangue , Anemia Ferropriva/sangue , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Pré-Escolar , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Orosomucoide/metabolismo , Prevalência , População Rural , Deficiência de Vitamina A/sangue , Zâmbia
6.
J Agric Food Chem ; 62(1): 136-43, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24341827

RESUMO

Biofortification to increase provitamin A carotenoids is an agronomic approach to alleviate vitamin A deficiency. Two studies compared biofortified foods using in vitro and in vivo methods. Study 1 screened maize genotypes (n = 44) using in vitro analysis, which demonstrated decreasing micellarization with increasing provitamin A. Thereafter, seven 50% biofortified maize feeds that hypothesized a one-to-one equivalency between ß-cryptoxanthin and ß-carotene were fed to Mongolian gerbils. Total liver retinol differed among the maize groups (P = 0.0043). Study 2 assessed provitamin A bioefficacy from 0.5% high-carotene carrots added to 60% staple-food feeds, followed by in vitro screening. Liver retinol was highest in the potato and banana groups, maize group retinol did not differ from baseline, and all treatments differed from control (P < 0.0001). In conclusion, ß-cryptoxanthin and ß-carotene have similar bioefficacy; meal matrix effects influence provitamin A absorption from carrot; and in vitro micellarization does not predict bioefficacy.


Assuntos
Ração Animal/análise , Carotenoides/metabolismo , Daucus carota/metabolismo , Gerbillinae/metabolismo , Zea mays/metabolismo , Animais , Carotenoides/análise , Criptoxantinas/análise , Criptoxantinas/metabolismo , Alimentos Fortificados/análise , Genótipo , Fígado/metabolismo , Zea mays/genética , beta Caroteno/análise , beta Caroteno/metabolismo
7.
J Nutr ; 142(12): 2097-104, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23096010

RESUMO

Banana is a staple crop in many regions where vitamin A deficiency is prevalent, making it a target for provitamin A biofortification. However, matrix effects may limit provitamin A bioavailability from bananas. The retinol bioefficacies of unripe and ripe bananas (study 1A), unripe high-provitamin A bananas (study 1B), and raw and cooked bananas (study 2) were determined in retinol-depleted Mongolian gerbils (n = 97/study) using positive and negative controls. After feeding a retinol-deficient diet for 6 and 4 wk in studies 1 and 2, respectively, customized diets containing 60, 30, or 15% banana were fed for 17 and 13 d, respectively. In study 1A, the hepatic retinol of the 60% ripe Cavendish group (0.52 ± 0.13 µmol retinol/liver) differed from baseline (0.65 ± 0.15 µmol retinol/liver) and was higher than the negative control group (0.39 ± 0.16 µmol retinol/liver; P < 0.0065). In study 1B, no groups differed from baseline (0.65 ± 0.15 µmol retinol/liver; P = 0.20). In study 2, the 60% raw Butobe group (0.68 ± 0.17 µmol retinol/liver) differed from the 60% cooked Butobe group (0.87 ± 0.24 µmol retinol/liver); neither group differed from baseline (0.80 ± 0.27 µmol retinol/liver; P < 0.0001). Total liver retinol was higher in the groups fed cooked bananas than in those fed raw (P = 0.0027). Body weights did not differ even though gerbils ate more green, ripe, and raw bananas than cooked, suggesting a greater indigestible component. In conclusion, thermal processing, but not ripening, improves the retinol bioefficacy of bananas. Food matrix modification affects carotenoid bioavailability from provitamin A biofortification targets.


Assuntos
Carotenoides/farmacocinética , Culinária , Alimentos Fortificados , Musa/metabolismo , Animais , Disponibilidade Biológica , Peso Corporal , Gerbillinae , Fígado/metabolismo , Masculino , Musa/química , Vitamina A/farmacocinética
8.
Food Nutr Bull ; 33(1): 63-71, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22624299

RESUMO

BACKGROUND: Vitamin A deficiency is associated with poor health outcomes related to reproduction, growth, vision, and immunity. Biofortification of staple crops is a novel strategy for combating vitamin A deficiency in high-risk populations where staple food intakes are high. African populations are proposed beneficiaries of maize (Zea mays) biofortified with provitamin A carotenoids, often called "orange maize" because of its distinctive deep yellow-orange kernels. The color facilitates ready recognition but presents a cultural challenge to maize-consuming populations, including those in much of Africa, who traditionally eat white varieties. OBJECTIVE: This study explores the intake patterns of, as well as adaptation to, traditional foods made with provitamin A-biofortified maize compared with white maize in rural Zambian children 3 to 5 years of age (n = 189) during a 3-month feeding trial. METHODS: The subjects were fed a breakfast of maize porridge (sweet mush), a lunch of maize nshima (stiff mush) with various side dishes, and an afternoon snack based on a 6-day rotating menu. The trial was conducted in 2010. The orange maize used in the trial came from three different sources. O1 maize was from the 2009 harvest and was stored in a freezer until use in 2010. O2 maize was also from the 2009 harvest and was stored in a cold room until 2010. O3 ("fresh") maize was from the 2010 harvest and was fed immediately after harvest in week 9 of the study and then stored in a freezer until milling for the final four weeks. RESULTS: Consumption of menu items, except snacks, was influenced by week (p < .0084). The intakes of porridge and nshima made with orange maize equaled those of porridge and nshima made with white maize from week 2 onward. The intakes of porridge and nshima prepared from O1 and O2 did not differ, but intakes became significantly higher when meals made from O3 were introduced (p < .014 for porridge and p < or = .013 for nshima). CONCLUSIONS: These results demonstrate quick adaptation to orange maize, a preference for recently harvested maize, and an optimistic outlook for similar adaptation patterns in other biofortified-maize target countries.


Assuntos
Carotenoides/metabolismo , Dieta , Preferências Alimentares , Alimentos Geneticamente Modificados , Pigmentos Biológicos/metabolismo , Sementes/metabolismo , Zea mays/metabolismo , Carotenoides/administração & dosagem , Comportamento Infantil/etnologia , Pré-Escolar , Serviços de Saúde Comunitária , Condimentos/análise , Dieta/etnologia , Grão Comestível/química , Fast Foods/análise , Manipulação de Alimentos , Preferências Alimentares/etnologia , Serviços de Alimentação , Promoção da Saúde , Humanos , Saúde da População Rural , Sementes/química , Deficiência de Vitamina A/prevenção & controle , Zâmbia , Zea mays/química
9.
Exp Biol Med (Maywood) ; 235(7): 839-48, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20558838

RESUMO

Fruits and vegetables are rich sources of provitamin A carotenoids. We evaluated the vitamin A (VA) bioefficacy of a whole foods supplement (WFS) and its constituent green vegetables (Study 1) and a variety of fruits with varying ratios of provitamin A carotenoids (Study 2) in VA-depleted Mongolian gerbils (n = 77/study). After feeding a VA-deficient diet for 4 and 6 weeks in Studies 1 and 2, respectively, customized diets, equalized for VA, were fed for 4 and 3 weeks, respectively. Both studies utilized negative and VA-positive control groups. In Study 1, liver VA was highest in the VA group (0.82 +/- 0.16 micromol/liver, P < 0.05), followed by brussels sprouts (0.50 +/- 0.15 micromol/liver), Betanat (beta-carotene from Blakeslea trispora) (0.50 +/- 0.12 micromol/liver) and spinach (0.47 +/- 0.09 micromol/liver) groups, which did not differ from baseline. The WFS (0.44 +/- 0.06 micromol/liver) and kale (0.43 +/- 0.14 micromol/liver) groups had lower liver VA than the baseline group (P < 0.05), but did not differ from the brussels sprouts, Betanat and spinach groups. In Study 2, liver VA was highest in the orange (0.67 +/- 0.18 micromol/liver), papaya (0.67 +/- 0.15 micromol/liver) and VA (0.66 +/- 0.14 micromol/liver) groups, followed by the mango (0.58 +/- 0.09 micromol/liver) and tangerine (0.55 +/- 0.15 micromol/liver) groups. These groups did not differ from baseline. The banana group (0.47 +/- 0.15 micromol/liver) was unable to maintain baseline stores of VA and did not differ from the control (0.46 +/- 0.13 mumol/liver). These fruits (except banana), vegetables and the WFS were able to prevent VA deficiency in Mongolian gerbils and could be an effective part of food-based interventions to support VA nutrition in developing countries and worldwide.


Assuntos
Carotenoides/metabolismo , Frutas , Verduras , Deficiência de Vitamina A/metabolismo , Animais , Brassica/química , Carica/química , Carotenoides/análise , Carotenoides/farmacologia , Citrus/química , Citrus sinensis/química , Criptoxantinas , Frutas/química , Gerbillinae , Fígado/química , Luteína/análise , Masculino , Mangifera/química , Spinacia oleracea/química , Verduras/química , Vitamina A/análise , Deficiência de Vitamina A/prevenção & controle , Xantofilas/análise , beta Caroteno/análise
10.
J Agric Food Chem ; 58(5): 2877-81, 2010 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-20131807

RESUMO

Purple carrots contain anthocyanins in addition to the provitamin A carotenoids in typical orange carrots. Simultaneous consumption of these phytochemicals in carrots may affect the bioavailability of carotenoids. The bioavailability of beta-carotene in humans was assessed from an acute feeding of orange (OC) and purple (PC) carrots with white (WC) as a control. Carrot smoothies were served to female subjects (n = 5, aged 21-26 years) for breakfast after 1 week on a low carotenoid diet and overnight fast. OC and PC smoothies were equalized to 10.3 mg of all-trans beta-carotene. Plasma beta-carotene was measured for 144 h following treatments. Peak plasma concentrations of OC and PC treatments did not differ. The PC treatment 0-144 h area-under-the-curve for beta-carotene was 76% of the OC treatment (P < 0.05). However, when the first 24 h were compared, OC and PC treatments did not differ, suggesting that anthocyanins in purple carrots do not affect the absorption of beta-carotene postprandially.


Assuntos
Antocianinas/farmacologia , Daucus carota/química , beta Caroteno/farmacocinética , Adulto , Área Sob a Curva , Disponibilidade Biológica , Feminino , Humanos , beta Caroteno/sangue
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