scholarly journals The possible significance of parallel changes in plasma lutein and retinol in Pakistani infants during the summer season

1997 ◽  
Vol 78 (5) ◽  
pp. 775-784 ◽  
Author(s):  
D. I. Thurnham ◽  
C. A. Northrop-Clewes ◽  
P. I. Paracha ◽  
U. J. McLoone

Recent evidence suggests that plasma lutein is better correlated than either β-carotene or lycopene with its respective carotenoid intake and therefore may be a better marker of vegetable intake than either β-carotene or lycopene. In the study reported in this paper, measurements of plasma carotenes and retinol were made in infants from two villages near Peshawar in the North West Frontier Province, Pakistan, in July and November 1993. The approximate age at the start was 14 months, and 101 boys and ninety girls completed the study. Of the usual plasma carotenes, only lutein was measurable in all samples and was correlated with retinol in both boys (r0.38,P< 0.0001;r0.35,P< 0.001) and girls (r0.21,P= 0.038;r0.307,P= 0.003) at the two time points respectively. In addition, the change in lutein was even more strongly correlated with the change in retinol in both boys (r0.453,P<0.0001) and girls (r0.439,P< 0.0001). In August β-carotene was measurable in approximately 8 % of samples and this increased to 31 % in November but there was no correlation between β-carotene and retinol at any time. There were negligible amounts of lycopene and β-cryptoxanthin in plasma at both time points. The mean concentration of plasma retinol in the infants was 0.66 μmol/l at baseline and 59 % of the infants had retinol concentrations < 0.7 μmol/l. In addition, there were fifteen infants whose levels were below 0.35 μmol/l suggesting that vitamin A status in the population was marginal. Food intake of the infants was not monitored in the present study but breast feeding continues for up to 2 years in this part of Pakistan and most infants would be weaned onto selected foods eaten by the family. The close correlation between plasma lutein and retinol suggests that the increase in retinol over the summer season may be attributable to an increased availability of green vegetables to the families. The source of lutein to the infants is most likely to be the breast milk since such vegetables are unlikely to be given to infants except to suck as a weaning food. The results may indicate the potential usefulness of plasma lutein as a marker of changes in vegetable intake and changes in vitamin A status in Third World infants and children.

1996 ◽  
Vol 76 (6) ◽  
pp. 809-820 ◽  
Author(s):  
Guangya Wang ◽  
Thierry A. Brun ◽  
Catherine A. Geissler ◽  
Banoo Parpia ◽  
Martin Root ◽  
...  

Vitamin A status of 260 groups of twenty-five males or twenty-five females, aged 35–64 years, surveyed in twenty-four provinces of the People's Republic of China, was assessed by measuring plasma retinol, retinol-binding protein and β-carotene concentrations. Direct measurements of food intake over a 3 d period and questionnaire data on the frequency of consumption of vegetables, fruit, animal products and other dietary items were also used. Vitamin A status appeared to be low only in specific counties but in general was satisfactory or only marginally deficient. Plasma harotene levels were strikingly low in comparison with Western levels despite generous vegetable consumption suggwg that intake of vitamin A precursors may have been adequate but not abundant enough to maintain high circulating plasma levels of β-carotene. Plasma β-carotene, for both males and females, was significantly correlated with the frequency of consumption of green vegetables. Plasma retinol, for males, was highly correlated with meat, fish, oil and alcohol consumption expresPed both in quantity or frequency of consumption. Higher levels of plasma retinol, together with lower levels of plasma β-carotene in males compared with females, suggest that men consume more animal products or may have higher retinol requirements and therefore a higher rate of conversion of β-carotene to retinol.


2009 ◽  
Vol 102 (3) ◽  
pp. 342-349 ◽  
Author(s):  
Julie A. Howe ◽  
Bussie Maziya-Dixon ◽  
Sherry A. Tanumihardjo

Efforts to increase β-carotene in cassava have been successful, but the ability of high-β-carotene cassava to prevent vitamin A deficiency has not been determined. Two studies investigated the bioefficacy of provitamin A in cassava and compared the effects of carotenoid content and variety on vitamin A status in vitamin A-depleted Mongolian gerbils (Meriones unguiculatus). Gerbils were fed a vitamin A-free diet 4 weeks prior to treatment. In Expt 1, treatments (ten gerbils per group) included 45 % high-β-carotene cassava, β-carotene and vitamin A supplements (intake matched to high-β-carotene cassava group), and oil control. In Expt 2, gerbils were fed cassava feeds with 1·8 or 4·3 nmol provitamin A/g prepared with two varieties. Gerbils were killed after 4 weeks. For Expt 1, liver vitamin A was higher (P < 0·05) in the vitamin A (1·45 (sd 0·23) μmol/liver), lower in the control (0·43 (sd 0·10) μmol/liver), but did not differ from the β-carotene group (0·77 (sd 0·12) μmol/liver) when compared with the high-β-carotene cassava group (0·69 (sd 0·20) μmol/liver). The bioconversion factor was 3·7 μg β-carotene to 1 μg retinol (2 mol:1 mol), despite 48 % cis-β-carotene [(Z)-β-carotene] composition in cassava. In Expt 2, cassava feed with 4·3 nmol provitamin A/g maintained vitamin A status. No effect of cassava variety was observed. Serum retinol concentrations did not differ. β-Carotene was detected in livers of gerbils receiving cassava and supplements, but the cis-to-trans ratio in liver differed from intake. Biofortified cassava adequately maintained vitamin A status and was as efficacious as β-carotene supplementation in the gerbil model.


1992 ◽  
Vol 68 (1) ◽  
pp. 283-291 ◽  
Author(s):  
Clive E. West ◽  
S. Reinder Sijtsma ◽  
Harry P. F. Peters ◽  
Jan H. W. M. Rombout ◽  
Akke J. Van Der Zijpp

Marginally vitamin A-deficient 1-d-old chickens capable of remaining healthy for at least 6 weeks were produced using a two-generation model. In this model, hens fed on diets with a limited vitamin A content were used to obtain 1-d-old chickens which were marginally deficient in vitamin A. Only hens with a narrow range of plasma retinol values (0.60–0.85 μmol/l) were satisfactory for this purpose. Above this range the 1-d-old chickens were not marginally vitamin A deficient. Below this range egg production and hatchability were affected to some extent depending on the degree of vitamin A deficiency. Even when egg production and hatchability remained at a high level in such birds, the 1-d-old chickens produced were not sufficiently strong to survive the first weeks of life. The advantages of the two-generation model for producing marginally vitamin A-deficient chickens are the increased uniformity and predictability of the chickens with respect to body-weight, general health and vitamin A status. However, it does take about 3 months to produce such chickens.


2020 ◽  
Vol 113 (1) ◽  
pp. 221-231
Author(s):  
Ibukun Afolami ◽  
Martin N Mwangi ◽  
Folake Samuel ◽  
Erick Boy ◽  
Paul Ilona ◽  
...  

ABSTRACT Background Vitamin A deficiency is a public health problem in sub-Saharan Africa. Pro-vitamin A biofortified (yellow) cassava has the potential to contribute significantly to improve vitamin A status, especially in populations that are difficult to reach with other strategies. Objectives The study aimed at determining the efficacy of biofortified cassava to improve vitamin A status of Nigerian preschool children. Methods An open-label randomized controlled trial was conducted in southwestern Nigeria. In total, 176 preschool children (aged 3–5 y) were randomized into 2 parallel arms comprising an experimental group (n = 88), fed foods prepared from biofortified (yellow) cassava, and a control group (n = 88), fed foods prepared from white cassava, twice a day, 6 d a week for 93 d. Results A total of 159 children completed the trial (yellow cassava group, n = 80; white cassava group, n = 79). Children consumed 221 and 74 µg/d retinol activity equivalents from intervention foods in the yellow and white cassava groups, respectively. The treatment effect on serum retinol concentrations at the end of the feeding trial was 0.06 µmol/L (95% CI: 0.004, 0.124 µmol/L), after adjustment for baseline retinol concentrations, inflammation, and asymptomatic malaria status. No significant treatment effects were detected for serum β-carotene (adjusted effect: 3.9%; 95% CI: −0.6%, 8.6%) and gut permeability (adjusted effect: 0.002; 95% CI: −0.089, 0.092), but a significant effect was detected for hemoglobin concentrations (adjusted effect: 3.08 g/L; 95% CI: 0.38, 5.78 g/L). Conclusions Daily consumption of β-carotene from biofortified cassava improved serum retinol and hemoglobin concentrations modestly in Nigerian preschool children. This study was registered with clinicaltrials.gov as NCT02627222.


2000 ◽  
Vol 83 (5) ◽  
pp. 513-520 ◽  
Author(s):  
Suzanne M. Filteau ◽  
Juana F. Willumsen ◽  
Keith Sullivan ◽  
Karin Simmank ◽  
Mary Gamble

The ratio plasma retinol-binding protein (RBP) : transthyretin (TTR) has been proposed as a means to improve the assessment of vitamin A status of individuals with concurrent infection or inflammation. We have measured RBP and TTR in stored sera from South African children who had accidentally ingested kerosene. Samples were collected from these children in hospital when suffering acute inflammation and respiratory distress, and from them and neighbourhood control children 3 months later. Vitamin A status was defined by modified relative dose response (MRDR) tests of liver retinol stores at 3 months and by serum retinol concentration both when children were ill and when they were well. Illness was defined as either being in hospital or, at follow-up, as having a raised plasma α1-acid glycoprotein (AGP) level. The RBP : TTR value was significantly decreased by both illness and low liver retinol stores. When the effects on RBP : TTR of illness and vitamin A stores were considered together for the 3-month follow-up samples, only vitamin A status significantly decreased the value. We calculated sensitivity and specificity of the RBP : TTR ratio against established measures of vitamin A status using a cut-off value of 0·3 for RBP : TTR and standard cut-off values for MRDR (0·06) and plasma retinol (0·7 μmol/l). Compared with MRDR, RBP : TTR had sensitivities of 76 % and 43 % and specificities of 22 % and 81 % to detect vitamin A deficiency in hospitalized and well children respectively. Compared with plasma retinol, sensitivities were 88 % and 44 % and specificities were 55 % and 64 % in hospitalized and well children respectively. Only for the case of clinically well children with biochemical evidence of subclinical inflammation did sensitivity (62 % and 100 % against MRDR and plasma retinol respectively) and specificity (100 % and 60 % against MRDR and retinol) approach useful levels for an assessment tool. Overall, although a trend supporting the theory behind the use of the RBP : TTR for assessment of vitamin A status in infection was observed in the current study, the ratio did not provide adequate sensitivity and specificity to be a useful assessment tool.


2008 ◽  
Vol 11 (1) ◽  
pp. 95-101 ◽  
Author(s):  
Consuelo Macías-Matos ◽  
Gisela Pita-Rodríguez ◽  
Pedro Monterrey-Gutiérrez ◽  
José Reboso-Pérez

AbstractObjective and settingA nationwide study was performed in Cuba to assess vitamin A status and the intake of vitamin-A-providing foods in children aged 6–11 years.Design and subjectsThe sample comprised 1191 schoolchildren from first to sixth grade, both sexes, from municipalities randomly selected from the five eastern provinces of Cuba in 2002 (first semester) and from the four western and four central provinces in 2003 (first semester). A food-frequency questionnaire was completed by 2038 mother-and-child pairs.ResultsMean (±standard deviation) plasma retinol concentrations were 1.77 ± 0.48 μmol l−1in the western, 2.01 ± 0.56 μmol l−1in the central and 1.40 ± 0.41 μmol l−1in the eastern region. No child had plasma retinol concentration below 0.35 μmol l−1, indicative of a high risk of clinical deficiency. Subclinical deficiency, plasma retinol concentration of 0.35–0.7 μmol l−1, was seen in <2% of subjects in all three regions and was <5% even in the two provinces with the worst vitamin A status (Guantánamo, 4.6%; Las Tunas, 3.0%). Adequate status (>1.05 μmol l−1) was present in >90% of subjects in all western and central provinces, and in one of the eastern provinces (Holguín), whereas in the four remaining eastern provinces, adequate status was present in >75%. Only nine fruits and vegetables were consumed frequently (>3 times per week) by >50% of children. Thirty-seven per cent regularly consumed a supplement containing vitamin A.ConclusionsMost Cuban children aged 6–11 years had adequate vitamin A status. Consumption of foods rich in vitamin and provitamin A, especially vegetables, was frequent but limited to a small variety of foods.


2016 ◽  
Vol 146 (10) ◽  
pp. 2129-2136 ◽  
Author(s):  
Michael H Green ◽  
Jennifer Lynn Ford ◽  
Anthony Oxley ◽  
Joanne Balmer Green ◽  
Hyunjin Park ◽  
...  

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