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Special Issue "Vitamin A and Carotenoids"

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A special issue of Nutrients (ISSN 2072-6643).

Deadline for manuscript submissions: closed (30 September 2013)

Special Issue Editors

Guest Editor
Dr. Loredana Quadro

Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, NJ 08901, USA
Phone: +1 732 9329611 x261
Fax: +1 732-9326776
Interests: mechanisms of maternal-fetal transfer of vitamin A and carotenoids; control of prostate epithelium proliferation by vitamin A signaling
Guest Editor
Dr. William S. Blaner

Department of Medicine, Columbia University, 650 W. 168th St., New York, NY 10032, USA
Phone: 212 305-5429
Fax: +1 212 305 2801
Interests: retinoid (vitamin A and its metabolites) metabolism and actions

Special Issue Information

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Keywords

  • pro-vitamin A  and non-provitamin A carotenoids
  • uptake, transport and metabolism in adult and developing tissues
  • mechanisms of action
  • health effects
  • metabolism and function of carotenoids in plants

Published Papers (13 papers)

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Research

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Open AccessArticle Carotenoid Biosynthetic and Catabolic Pathways: Gene Expression and Carotenoid Content in Grains of Maize Landraces
Nutrients 2014, 6(2), 546-563; doi:10.3390/nu6020546
Received: 11 September 2013 / Revised: 19 November 2013 / Accepted: 10 December 2013 / Published: 28 January 2014
Cited by 6 | PDF Full-text (1877 KB) | HTML Full-text | XML Full-text
Abstract
Plant carotenoids have been implicated in preventing several age-related diseases, and they also provide vitamin A precursors; therefore, increasing the content of carotenoids in maize grains is of great interest. It is not well understood, however, how the carotenoid biosynthetic pathway is [...] Read more.
Plant carotenoids have been implicated in preventing several age-related diseases, and they also provide vitamin A precursors; therefore, increasing the content of carotenoids in maize grains is of great interest. It is not well understood, however, how the carotenoid biosynthetic pathway is regulated. Fortunately, the maize germplasm exhibits a high degree of genetic diversity that can be exploited for this purpose. Here, the accumulation of carotenoids and the expression of genes from carotenoid metabolic and catabolic pathways were investigated in several maize landraces. The carotenoid content in grains varied from 10.03, in the white variety MC5, to 61.50 μg·g−1, in the yellow-to-orange variety MC3, and the major carotenoids detected were lutein and zeaxanthin. PSY1 (phythoene synthase) expression showed a positive correlation with the total carotenoid content. Additionally, the PSY1 and HYD3 (ferredoxin-dependent di-iron monooxygenase) expression levels were positively correlated with β-cryptoxanthin and zeaxanthin, while CYP97C (cytochrome P450-type monooxygenase) expression did not correlate with any of the carotenoids. In contrast, ZmCCD1 (carotenoid dioxygenase) was more highly expressed at the beginning of grain development, as well as in the white variety, and its expression was inversely correlated with the accumulation of several carotenoids, suggesting that CCD1 is also an important enzyme to be considered when attempting to improve the carotenoid content in maize. The MC27 and MC1 varieties showed the highest HYD3/CYP97C ratios, suggesting that they are promising candidates for increasing the zeaxanthin content; in contrast, MC14 and MC7 showed low HYD3/CYP97C, suggesting that they may be useful in biofortification efforts aimed at promoting the accumulation of provitamin A. The results of this study demonstrate the use of maize germplasm to provide insight into the regulation of genes involved in the carotenoid pathway, which would thus better enable us to select promising varieties for biofortification efforts. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessArticle Effects of Vitamin A Supplementation on Iron Status Indices and Iron Deficiency Anaemia: A Randomized Controlled Trial
Nutrients 2014, 6(1), 190-206; doi:10.3390/nu6010190
Received: 21 October 2013 / Revised: 11 November 2013 / Accepted: 14 November 2013 / Published: 31 December 2013
Cited by 3 | PDF Full-text (1169 KB) | HTML Full-text | XML Full-text
Abstract
Iron deficiency anaemia (IDA) is the most common nutritional deficiency in the world including developed and developing countries. Despite intensive efforts to improve the quality of life of rural and aboriginal communities in Malaysia, anaemia and IDA are still major public health [...] Read more.
Iron deficiency anaemia (IDA) is the most common nutritional deficiency in the world including developed and developing countries. Despite intensive efforts to improve the quality of life of rural and aboriginal communities in Malaysia, anaemia and IDA are still major public health problems in these communities particularly among children. A randomized, double-blind, placebo-controlled trial was conducted on 250 Orang Asli (aboriginal) schoolchildren in Malaysia to investigate the effects of a single high-dose of vitamin A supplementation (200,000 IU) on iron status indices, anaemia and IDA status. The effect of the supplement was assessed after 3 months of receiving the supplements; after a complete 3-day deworming course of 400 mg/day of albendazole tablets. The prevalence of anaemia was found to be high: 48.5% (95% CI = 42.3, 54.8). Moreover, 34% (95% CI = 28.3, 40.2) of the children had IDA, which accounted for 70.1% of the anaemic cases. The findings showed that the reduction in serum ferritin level and the increments in haemoglobin, serum iron and transferrin saturation were found to be significant among children allocated to the vitamin A group compared to those allocated to the placebo group (p < 0.01). Moreover, a significant reduction in the prevalence of IDA by almost 22% than prevalence at baseline was reported among children in the vitamin A group compared with only 2.3% reduction among children in the placebo group. In conclusion, vitamin A supplementation showed a significant impact on iron status indices and IDA among Orang Asli children. Hence, providing vitamin A supplementation and imparting the knowledge related to nutritious food should be considered in the efforts to improve the nutritional and health status of these children as a part of efforts to improve the quality of life in rural and aboriginal communities. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Figures

Open AccessArticle Food Predictors of Plasma Carotenoids
Nutrients 2013, 5(10), 4051-4066; doi:10.3390/nu5104051
Received: 1 August 2013 / Revised: 10 September 2013 / Accepted: 13 September 2013 / Published: 11 October 2013
Cited by 8 | PDF Full-text (250 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Empirical prediction models that weight food frequency questionnaire (FFQ) food items by their relation to nutrient biomarker concentrations may estimate nutrient exposure better than nutrient intakes derived from food composition databases. Carotenoids may especially benefit because contributing foods vary in bioavailability and [...] Read more.
Empirical prediction models that weight food frequency questionnaire (FFQ) food items by their relation to nutrient biomarker concentrations may estimate nutrient exposure better than nutrient intakes derived from food composition databases. Carotenoids may especially benefit because contributing foods vary in bioavailability and assessment validity. Our objective was to develop empirical prediction models for the major plasma carotenoids and total carotenoids and evaluate their validity compared with dietary intakes calculated from standard food composition tables. 4180 nonsmoking women in the Nurses’ Health Study (NHS) blood subcohort with previously measured plasma carotenoids were randomly divided into training (n = 2787) and testing (n = 1393) subsets. Empirical prediction models were developed in the training subset by stepwise selection from foods contributing ≥0.5% to intake of the relevant carotenoid. Spearman correlations between predicted and measured plasma concentrations were compared to Spearman correlations between dietary intake and measured plasma concentrations for each carotenoid. Three to 12 foods were selected for the α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, lycopene, and total carotenoids prediction models. In the testing subset, Spearman correlations with measured plasma concentrations for the calculated dietary intakes and predicted plasma concentrations, respectively, were 0.31 and 0.37 for α-carotene, 0.29 and 0.31 for β-carotene, 0.36 and 0.41 for β-cryptoxanthin, 0.28 and 0.31 for lutein/zeaxanthin, 0.22 and 0.23 for lycopene, and 0.22 and 0.27 for total carotenoids. Empirical prediction models may modestly improve assessment of some carotenoids, particularly α-carotene and β-cryptoxanthin. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessArticle Lycopene Supplement and Blood Pressure: An Updated Meta-Analysis of Intervention Trials
Nutrients 2013, 5(9), 3696-3712; doi:10.3390/nu5093696
Received: 19 July 2013 / Revised: 9 September 2013 / Accepted: 12 September 2013 / Published: 18 September 2013
Cited by 6 | PDF Full-text (508 KB) | HTML Full-text | XML Full-text
Abstract
Epidemiological studies suggested that lycopene supplement could decrease blood pressure, but the results were conflicting. We conducted an updated meta-analysis by screening PubMed databases, and calculated the combined effect size using a random effect model. In addition, subgroup analysis stratified by baseline [...] Read more.
Epidemiological studies suggested that lycopene supplement could decrease blood pressure, but the results were conflicting. We conducted an updated meta-analysis by screening PubMed databases, and calculated the combined effect size using a random effect model. In addition, subgroup analysis stratified by baseline blood pressure, lycopene dosage, duration, study location and the funding support of the paper was also conducted. Six studies met our inclusion criteria, and the pooled analysis demonstrated a significant reduction of systolic blood pressure (SBP) (mean SBP = −4.953 [−8.820, −1.086], p = 0.012) with obvious heterogeneity (p = 0.034, I2 = 58.5%). Subgroup analysis results showed that higher dosage of lycopene supplement (>12 mg/day) could lower SBP more significantly, especially for participants with baseline SBP >120 mmHg, or Asians, while lycopene intervention had no statistical effect on diastolic blood pressure (DBP) (mean DBP = −3.809 [−8.177, 0.560], p = 0.087), and obvious heterogeneity was also observed (p = 0.074, I2 = 53.1%). Our present study suggests that lycopene supplement >12 mg/day might effectively decrease SBP, particularly among Asians or population with higher baseline SBP. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)

Review

Jump to: Research

Open AccessReview Metabolic Interactions between Vitamin A and Conjugated Linoleic Acid
Nutrients 2014, 6(3), 1262-1272; doi:10.3390/nu6031262
Received: 23 December 2013 / Revised: 4 March 2014 / Accepted: 10 March 2014 / Published: 24 March 2014
PDF Full-text (1162 KB) | HTML Full-text | XML Full-text
Abstract
Lipid-soluble molecules share several aspects of their physiology due to their common adaptations to a hydrophilic environment, and may interact to regulate their action in a tissue-specific manner. Dietary conjugated linoleic acid (CLA) is a fatty acid with a conjugated diene structure [...] Read more.
Lipid-soluble molecules share several aspects of their physiology due to their common adaptations to a hydrophilic environment, and may interact to regulate their action in a tissue-specific manner. Dietary conjugated linoleic acid (CLA) is a fatty acid with a conjugated diene structure that is found in low concentrations in ruminant products and available as a nutritional supplement. CLA has been shown to increase tissue levels of retinol (vitamin A alcohol) and its sole specific circulating carrier protein retinol-binding protein (RBP or RBP4). However, the precise mechanism of this action has not been elucidated yet. Here, we provide a summary of the current knowledge in this specific area of research and speculate that retinol and CLA may compete for catabolic pathways modulated by the activity of PPAR-α and RXR heterodimer. We also present preliminary data that may position PPAR-α at the crossroads between the metabolism of lipids and vitamin A. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview Vitamin A/Retinol and Maintenance of Pluripotency of Stem Cells
Nutrients 2014, 6(3), 1209-1222; doi:10.3390/nu6031209
Received: 2 December 2013 / Revised: 21 February 2014 / Accepted: 24 February 2014 / Published: 21 March 2014
Cited by 4 | PDF Full-text (319 KB) | HTML Full-text | XML Full-text
Abstract
Retinol, the alcohol form of vitamin A is a key dietary component that plays a critical role in vertebrate development, cell differentiation, reproduction, vision and immune system. Natural and synthetic analogs of retinol, called retinoids, have generally been associated with the cell [...] Read more.
Retinol, the alcohol form of vitamin A is a key dietary component that plays a critical role in vertebrate development, cell differentiation, reproduction, vision and immune system. Natural and synthetic analogs of retinol, called retinoids, have generally been associated with the cell differentiation via retinoic acid which is the most potent metabolite of retinol. However, a direct function of retinol has not been fully investigated. New evidence has now emerged that retinol supports the self-renewal of stem cells including embryonic stem cells (ESCs), germ line stem cells (GSCs) and cancer stem cells (CSCs) by activating the endogenous machinery for self-renewal by a retinoic acid independent mechanism. The studies have also revealed that stem cells do not contain enzymes that are responsible for metabolizing retinol into retinoic acid. This new function of retinol may have important implications for stem cell biology which can be exploited for quantitative production of pure population of pluripotent stem cells for regenerative medicine as well as clinical applications for cancer therapeutics. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview Aldehyde Dehydrogenase 1A1: Friend or Foe to Female Metabolism?
Nutrients 2014, 6(3), 950-973; doi:10.3390/nu6030950
Received: 26 November 2013 / Revised: 8 February 2014 / Accepted: 18 February 2014 / Published: 3 March 2014
Cited by 8 | PDF Full-text (876 KB) | HTML Full-text | XML Full-text
Abstract
In this review, we summarize recent advances in understanding vitamin A-dependent regulation of sex-specific differences in metabolic diseases, inflammation, and certain cancers. We focus on the characterization of the aldehyde dehydrogenase-1 family of enzymes (ALDH1A1, ALDH1A2, ALDH1A3) that catalyze conversion of retinaldehyde [...] Read more.
In this review, we summarize recent advances in understanding vitamin A-dependent regulation of sex-specific differences in metabolic diseases, inflammation, and certain cancers. We focus on the characterization of the aldehyde dehydrogenase-1 family of enzymes (ALDH1A1, ALDH1A2, ALDH1A3) that catalyze conversion of retinaldehyde to retinoic acid. Additionally, we propose a “horizontal transfer of signaling” from estrogen to retinoids through the action of ALDH1A1. Although estrogen does not directly influence expression of Aldh1a1, it has the ability to suppress Aldh1a2 and Aldh1a3, thereby establishing a female-specific mechanism for retinoic acid generation in target tissues. ALDH1A1 regulates adipogenesis, abdominal fat formation, glucose tolerance, and suppression of thermogenesis in adipocytes; in B cells, ALDH1A1 plays a protective role by inducing oncogene suppressors Rara and Pparg. Considering the conflicting responses of Aldh1a1 in a multitude of physiological processes, only tissue-specific regulation of Aldh1a1 can result in therapeutic effects. We have shown through successful implantation of tissue-specific Aldh1a1−/− preadipocytes that thermogenesis can be induced in wild-type adipose tissues to resolve diet-induced visceral obesity in females. We will briefly discuss the emerging role of ALDH1A1 in multiple myeloma, the regulation of reproduction, and immune responses, and conclude by discussing the role of ALDH1A1 in future therapeutic applications. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Figures

Open AccessReview Potential Role of Carotenoids as Antioxidants in Human Health and Disease
Nutrients 2014, 6(2), 466-488; doi:10.3390/nu6020466
Received: 2 December 2013 / Revised: 19 December 2013 / Accepted: 2 January 2014 / Published: 27 January 2014
Cited by 57 | PDF Full-text (292 KB) | HTML Full-text | XML Full-text
Abstract
Carotenoids constitute a ubiquitous group of isoprenoid pigments. They are very efficient physical quenchers of singlet oxygen and scavengers of other reactive oxygen species. Carotenoids can also act as chemical quenchers undergoing irreversible oxygenation. The molecular mechanisms underlying these reactions are still [...] Read more.
Carotenoids constitute a ubiquitous group of isoprenoid pigments. They are very efficient physical quenchers of singlet oxygen and scavengers of other reactive oxygen species. Carotenoids can also act as chemical quenchers undergoing irreversible oxygenation. The molecular mechanisms underlying these reactions are still not fully understood, especially in the context of the anti- and pro-oxidant activity of carotenoids, which, although not synthesized by humans and animals, are also present in their blood and tissues, contributing to a number of biochemical processes. The antioxidant potential of carotenoids is of particular significance to human health, due to the fact that losing antioxidant-reactive oxygen species balance results in “oxidative stress”, a critical factor of the pathogenic processes of various chronic disorders. Data coming from epidemiological studies and clinical trials strongly support the observation that adequate carotenoid supplementation may significantly reduce the risk of several disorders mediated by reactive oxygen species. Here, we would like to highlight the beneficial (protective) effects of dietary carotenoid intake in exemplary widespread modern civilization diseases, i.e., cancer, cardiovascular or photosensitivity disorders, in the context of carotenoids’ unique antioxidative properties. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview Non-Alcoholic Steatohepatitis and Hepatocellular Carcinoma: Implications for Lycopene Intervention
Nutrients 2014, 6(1), 124-162; doi:10.3390/nu6010124
Received: 25 October 2013 / Revised: 9 December 2013 / Accepted: 11 December 2013 / Published: 27 December 2013
Cited by 14 | PDF Full-text (4570 KB) | HTML Full-text | XML Full-text
Abstract
Increased prevalence of non-alcoholic fatty liver disease (NAFLD) is one of the consequences of the current obesity epidemic. NAFLD is a major form of chronic liver disease that is highly prevalent in obese and overweight adults and children. Nonalcoholic steatohepatitis (NASH) is [...] Read more.
Increased prevalence of non-alcoholic fatty liver disease (NAFLD) is one of the consequences of the current obesity epidemic. NAFLD is a major form of chronic liver disease that is highly prevalent in obese and overweight adults and children. Nonalcoholic steatohepatitis (NASH) is the severe form of NAFLD, and uncontrolled inflammation as displayed in NASH has been identified as one of the key events in enhancing hepatic carcinogenesis. Lycopene is a non-provitamin A carotenoid and the pigment principally responsible for the characteristic deep-red color of ripe tomato and tomato products, as well as some fruits and vegetables. Lycopene’s innate antioxidant and anti-inflammatory properties have generated research interests on its capacity to protect against human diseases that are associated with oxidative stress and inflammation. In addition, differential mechanisms of lycopene metabolism including endogenous cleavage by carotenoid cleavage oxygenases (BCOs), generate lycopene metabolites that may also have significant impact on human disease development. However, it remains to be elucidated as to whether lycopene or its metabolites apolycopenoids have protective effects against obesity-related complications including inflammation and tumorigenesis. This article summarizes the in vivo experiments that elucidated molecular mechanisms associated with obesity-related hepatic inflammation and carcinogenesis. This review also provides an overview of lycopene metabolism, and the molecular pathways involved in the potential beneficial properties of lycopene and apolycopenoids. More research is clearly needed to fully unravel the importance of BCOs in tomato carotenoid metabolism and the consequence on human health and diseases. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview Mammalian Metabolism of β-Carotene: Gaps in Knowledge
Nutrients 2013, 5(12), 4849-4868; doi:10.3390/nu5124849
Received: 14 October 2013 / Revised: 14 November 2013 / Accepted: 15 November 2013 / Published: 27 November 2013
Cited by 6 | PDF Full-text (466 KB) | HTML Full-text | XML Full-text
Abstract
β-carotene is the most abundant provitamin A carotenoid in human diet and tissues. It exerts a number of beneficial functions in mammals, including humans, owing to its ability to generate vitamin A as well as to emerging crucial signaling functions of its [...] Read more.
β-carotene is the most abundant provitamin A carotenoid in human diet and tissues. It exerts a number of beneficial functions in mammals, including humans, owing to its ability to generate vitamin A as well as to emerging crucial signaling functions of its metabolites. Even though β-carotene is generally considered a safer form of vitamin A due to its highly regulated intestinal absorption, detrimental effects have also been ascribed to its intake, at least under specific circumstances. A better understanding of the metabolism of β-carotene is still needed to unequivocally discriminate the conditions under which it may exert beneficial or detrimental effects on human health and thus to enable the formulation of dietary recommendations adequate for different groups of individuals and populations worldwide. Here we provide a general overview of the metabolism of this vitamin A precursor in mammals with the aim of identifying the gaps in knowledge that call for immediate attention. We highlight the main questions that remain to be answered in regards to the cleavage, uptake, extracellular and intracellular transport of β-carotene as well as the interactions between the metabolism of β-carotene and that of other macronutrients such as lipids. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview The Influence of Vitamin A Supplementation on Iron Status
Nutrients 2013, 5(11), 4399-4413; doi:10.3390/nu5114399
Received: 16 September 2013 / Revised: 10 October 2013 / Accepted: 30 October 2013 / Published: 7 November 2013
Cited by 5 | PDF Full-text (228 KB) | HTML Full-text | XML Full-text
Abstract
Vitamin A (VA) and iron deficiencies are important nutritional problems, affecting particularly preschool children, as well as pregnant and lactating women. A PubMed (National Library of Medicine, National Institutes of Health, Bethesda, MD, USA) literature review was carried out to search for [...] Read more.
Vitamin A (VA) and iron deficiencies are important nutritional problems, affecting particularly preschool children, as well as pregnant and lactating women. A PubMed (National Library of Medicine, National Institutes of Health, Bethesda, MD, USA) literature review was carried out to search for clinical trials published from 1992 to 2013 that assessed the influence of vitamin A supplementation on iron status. Simultaneous use of iron and vitamin A supplements seemed to be more effective to prevent iron deficiency anemia than the use of these micronutrients alone. Some studies did not include a placebo group and only a few of them assessed vitamin A status of the individuals at baseline. Moreover, the studies did not consider any inflammatory marker and a reasonable number of iron parameters. Another important limitation was the lack of assessment of hemoglobin variants, especially in regions with a high prevalence of anemia. Assessment of hemoglobin variants, inflammatory markers and anemia of chronic inflammation would be important to the studies investigated. Studies involving different populations are necessary to elucidate the interaction between the two micronutrients, especially regarding iron absorption and modulation of erythropoiesis. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview Absorption of Vitamin A and Carotenoids by the Enterocyte: Focus on Transport Proteins
Nutrients 2013, 5(9), 3563-3581; doi:10.3390/nu5093563
Received: 24 June 2013 / Revised: 19 August 2013 / Accepted: 26 August 2013 / Published: 12 September 2013
Cited by 20 | PDF Full-text (331 KB) | HTML Full-text | XML Full-text
Abstract
Vitamin A deficiency is a public health problem in most developing countries, especially in children and pregnant women. It is thus a priority in health policy to improve preformed vitamin A and/or provitamin A carotenoid status in these individuals. A more accurate [...] Read more.
Vitamin A deficiency is a public health problem in most developing countries, especially in children and pregnant women. It is thus a priority in health policy to improve preformed vitamin A and/or provitamin A carotenoid status in these individuals. A more accurate understanding of the molecular mechanisms of intestinal vitamin A absorption is a key step in this direction. It was long thought that β-carotene (the main provitamin A carotenoid in human diet), and thus all carotenoids, were absorbed by a passive diffusion process, and that preformed vitamin A (retinol) absorption occurred via an unidentified energy-dependent transporter. The discovery of proteins able to facilitate carotenoid uptake and secretion by the enterocyte during the past decade has challenged established assumptions, and the elucidation of the mechanisms of retinol intestinal absorption is in progress. After an overview of vitamin A and carotenoid fate during gastro-duodenal digestion, our focus will be directed to the putative or identified proteins participating in the intestinal membrane and cellular transport of vitamin A and carotenoids across the enterocyte (i.e., Scavenger Receptors or Cellular Retinol Binding Proteins, among others). Further progress in the identification of the proteins involved in intestinal transport of vitamin A and carotenoids across the enterocyte is of major importance for optimizing their bioavailability. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)
Open AccessReview A Comparison of Retinyl Palmitate and Red Palm Oil β-Carotene as Strategies to Address Vitamin A Deficiency
Nutrients 2013, 5(8), 3257-3271; doi:10.3390/nu5083257
Received: 4 June 2013 / Revised: 4 August 2013 / Accepted: 6 August 2013 / Published: 15 August 2013
Cited by 3 | PDF Full-text (415 KB) | HTML Full-text | XML Full-text
Abstract
Vitamin A deficiency continues to be an international public health problem with several important health consequences including blindness and overall increased rates of morbidity and mortality. To address this widespread issue, a series of strategies have been put into place from dietary [...] Read more.
Vitamin A deficiency continues to be an international public health problem with several important health consequences including blindness and overall increased rates of morbidity and mortality. To address this widespread issue, a series of strategies have been put into place from dietary diversification to supplementation and fortification programs. Retinyl palmitate has been used successfully for decades as a supplement as well as a way to fortify numerous foods, including vegetable oil, rice, monosodium glutamate, cereal flours and sugar. Recently, there has been rising interest in using a natural source of carotenoids, β-carotene from red palm oil (RPO), for fortification. Although RPO interventions have also been shown to effectively prevent Vitamin A deficiency, there are numerous challenges in using beta-carotene from RPO as a fortification technique. β-Carotene can induce significant changes in appearance and taste of the fortified product. Moreover, costs of fortifying with beta-carotene are higher than with retinyl palmitate. Therefore, RPO should only be used as a source of Vitamin A if it is produced and used in its crude form and regularly consumed without frying. Furthermore, refined RPO should be fortified with retinyl palmitate, not β-carotene, to ensure that there is adequate Vitamin A content. Full article
(This article belongs to the Special Issue Vitamin A and Carotenoids)

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