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The wave of individuals impacted by dementia continues to rise rapidly as worldwide lifespan increases. Dietary strategies to slow cognitive decline and prolong time to clinical dementia remain understudied, but with potentially powerful public health consequences. Indeed, previously conducted large, randomized, placebo‐controlled trials of micronutrients remain an under‐leveraged resource to study changes in cognitive performance. As a motivating example, we highlight an ancillary report from the Physicians' Health Study, where subjects randomized to β‐carotene (a provitamin A carotenoid) had a more attenuated change in longitudinal global cognitive performance and verbal memory, as compared to subjects randomized to placebo. Despite mechanistic evidence from cell and animal studies supporting a vitamin A‐mediated role in the biology associated with cognition, limited follow‐up work has been conducted. We argue that dietary factors (including provitamin A) deserve a second look, leveraging multi‐omic approaches, to elucidate how they may mitigate cognitive decline and dementia risk. [ABSTRACT FROM AUTHOR]

Vitamin A deficiency in sub-Saharan Africa is mainly being addressed through crop biofortification. Several high provitamin A (PVA) maize varieties have been released as part of these measures. However, these varieties are grown in areas where Aspergillus ear rot (AER) and Fusarium ear rot (FER) frequently occur, leading to contamination with mycotoxins, which in turn reduce the yield and grain quality. Chronic mycotoxin exposure leads to serious public health problems. Therefore, PVA maize varieties should be resistant to mycotoxin contamination. In a previous study, we generated 120 PVA hybrids by crossing 60 PVA inbreds and two testers with contrasting PVA content. Several inbreds resistant to aflatoxin were detected through laboratory-based kernel screening assays. In the current study, 21 PVA inbred lines with varying carotenoid content inoculated with toxigenic isolates of A. flavus and F. verticillioides were evaluated in field trials conducted at two locations in Nigeria for resistance to ear rots and mycotoxin production. Inbred lines resistant to AER, FER, aflatoxin and fumonisin contamination were identified. High PVA inbred lines were less susceptible to the ear rots, aflatoxin, and fumonisin than those with low PVA content. There were negative correlations between PVA content and each of AER (r = −0.28, P < 0.0001), FER (r = −0.37, P < 0.0001), aflatoxin (r = −0.15, P < 0.05), and fumonisin (r = −0.27, P < 0.0001). Three promising inbred lines were resistant to both aflatoxin and fumonisin. Moreover, the inbred TZI1715 combined resistance to AER, FER, aflatoxin, and fumonisin with desirable general combining ability for high β-carotene and total PVA content. These results suggest that the PVA biofortified maize developed to address vitamin A deficiency can also contribute to reduced exposure to aflatoxin and fumonisin. • Several PVA maize lines were resistant to ear rots and mycotoxins in field trials. • Parental lines to develop PVA hybrids with reduced mycotoxin levels were detected. • High PVA maize reduces aflatoxin and fumonisin accumulation. • High PVA maize has a dual health benefit: increased vitamin A and reduced mycotoxin exposure. [ABSTRACT FROM AUTHOR]

Objective: To determine the micronutrient composition of fresh and boiled traditional green leafy vegetables (TGLVs). Design: Sixteen TGLVs categorised into cultivated and uncultivated vegetables were analysed for vitamin C (ascorbic acid [AA] and dehydroascorbate [DHAA]), β-carotene, lutein and minerals. Results: Basella alba had the highest AA (72 mg/100 g) content; Vernonia amygdalina (unwashed), had the highest β-carotene and lutein concentrations (14.1 and 29.0 mg/100 g, respectively); Amaranthus hybridus had the highest AA (43 mg/100 g) and β-carotene (9.3 mg/100 g) content, for cultivated sp. Celosia argentea had the highest Fe content; Zn content of all the vegetables was low, 0.4–2.6 mg/100 g. Cooking resulted in significant losses in AA content in all the samples, 19% in B. alba to 100% in Crassocephalum crepidioides. Carotenoid losses were observed in 10 samples and six samples had increased values of β-carotene (12% to 183%) and lutein (64% to double). Conclusion: Traditional green leafy vegetables studied were found to be rich in the micronutrients of interest, especially in carotenoids. Boiling of leafy vegetables, as traditionally done, led to considerable losses of the micronutrients. The micronutrient content of uncultivated leafy vegetables compared well with commonly cultivated species. [ABSTRACT FROM AUTHOR]

Abstract Poverty eradication and global food security are among the targets of world leaders, most especially combating the scourge of hidden hunger. Provitamin A carotenoids cannot be synthesized de novo by human and so it must be taken as part of the diet. The deficiency of which is causing almost 6000 sights to be lost daily in most developing countries because of the monotonous starchy diets lacking substantial amount of carotenoid. Conventional breeding as well as genetic engineering have been used to increase the level of carotenoid in many staples including rice, potato, maize and cassava. While products from genetic engineering are still been subjected to strict regulatory measures preventing the delivery of the products to target consumers, some of the products from conventional breeding are already on the table of consumers. Interestingly, both technologies are crucial to tackling micronutrient deficiencies. This review discusses the role of carotenoid in human, the biosynthesis in plant and some of the staple crops that have been modified for increased carotenoid. Some measures expected of the leaders of the countries in need of these products for safe delivery to the target population after two decades is also highlighted. [ABSTRACT FROM AUTHOR]

Background: Vitamin A (VA) deficiency (VAD) is still a concern in many parts of the world, and multiple intervention strategies are being implemented to reduce the prevalence of VAD and associated morbidity and mortality. Because some individuals within a population may be exposed to multiple VA interventions, concerns have been raised about the possible risk of hypervitaminosis A.Objectives: A consultative meeting was held in Vienna, Austria, in March 2014 to (1) review current knowledge concerning the safety and effectiveness of large-scale programs to control VAD, (2) develop a related research agenda, and (3) review current available methods to assess VA status and risk of hypervitaminosis A.Methods: Multiple countries were represented and shared their experiences using a variety of assessment methods, including retinol isotope dilution (RID) techniques. Discussion included next steps to refine assessment methodology, investigate RID limitations under different conditions, and review programmatic approaches to ensure VA adequacy and avoid excessive intakes.Results: Fortification programs have resulted in adequate VA status in Guatemala, Zambia, and parts of Cameroon. Dietary patterns in several countries revealed that some people may consume excessive preformed VA from fortified foods.Conclusion: Additional studies are needed to compare biomarkers of tissue damage to RID methods during hypervitaminosis A and to determine what other biomarkers can be used to assess excessive preformed VA intake. [ABSTRACT FROM AUTHOR]

The article discusses a study to examine the effects of non-provitamin A carotenoids on hyaluronan production in human keratinocytes. It determines the physiological effects of non-provitamin A carotenoids in cultured keratinocytes and investigates the retinoic acid receptor (RAR) stimulation activity of non-provitamin A by monitoring production of keratinocyte hyaluronan. The study mentions about carotenoids including lutein and zeaxanthin which are found in human retina.

Abstract: Biofortification, the process of breeding nutrients into food crops, provides a sustainable, long-term strategy for delivering micronutrients to rural populations in developing countries. Crops are being bred for higher levels of micronutrients using both conventional and transgenic breeding methods; several conventional varieties have been released, while additional conventional and transgenic varieties are in the breeding pipeline. The results of efficacy and effectiveness studies, as well as recent successes in delivery, provide evidence that biofortification is a promising strategy for combating hidden hunger. This review highlights progress to date and identifies challenges faced in delivering biofortified crops. [Copyright &y& Elsevier]

Objectives: To assess the acceptance of popular maize food products (phutu, thin porridge and samp), prepared with yellow, provitamin A-biofortified maize varieties, in 212 subjects between the ages of three and 55 years, from rural KwaZulu-Natal. Design: A cross-sectional study. Method: Preschool, primary school and secondary school subjects were randomly selected from two primary schools and one secondary school, respectively, while adult subjects constituted a convenience sample. Pre- and primary school children completed a paired preference test. Secondary school and adult subjects completed a five-point facial hedonic and a preference ranking test. Focus group discussions were conducted using adult subjects. Results: Preschool children preferred yellow maize to white maize food products: phutu (81% vs. 19%; p-value < 0.001), thin porridge (75% vs. 25%; p-value < 0.001) and samp (73% vs. 27%; p-value < 0.001). There was no statistically significant difference in preference for white and yellow maize by primary school children. Secondary school and adult subjects preferred white maize to yellow maize. Focus group discussions confirmed the preference for white maize by the adults. Conclusion: The study findings suggest that yellow, provitamin A-biofortified maize has the potential to succeed as a new strategy of dealing with the serious problem of vitamin A deficiency, especially among children of preschool age. However, in older groups, this strategy is unlikely to be successful, unless other strategies are implemented, including intensive nutrition education programmes on the nutritional benefits of the maize, targeting the market price at which yellow maize is sold, increasing its availability in local grocery stores, and improving its sensory properties through breeding. [ABSTRACT FROM AUTHOR]

Background: The use of conventional breeding techniques and biotechnology to improve the micronutrient quality of staple crops is a new strategy to address micronutrient deficiencies in developing countries. This strategy, referred to as "biofortification," is being developed and implemented through the international alliance of HarvestPlus to improve iron, zinc, and vitamin A status in low-income populations.Objective: The objective of this paper is to review the challenges faced by nutritionists to determine and demonstrate the ability of biofortified crops to have an impact on the nutritional and health status of target populations.Methods: We reviewed available published and unpublished information that is needed to design and evaluate this strategy, including issues related to micronutrient retention in staple foods, micronutrient bioavailability from plant foods, and evidence for the efficacy of high-micronutrient-content staple foods to improve micronutrient status.Results: Further information is needed on the retention of micronutrients in staple foods, in particular of provitamin A carotenoids, when stored and prepared under different conditions. The low bioavailability of iron from staple foods and the ability to demonstrate an impact on zinc status are specific challenges that need to be addressed. In target countries, infections and other micronutrient deficiencies may confound the ability to affect micronutrient status, and this must be taken into account in community-based studies.Conclusions: Information to date suggests that biofortification has the potential to contribute to increased micronutrient intakes and improved micronutrient status. The success of this strategy will require the collaboration between health and agriculture sectors. [ABSTRACT FROM AUTHOR]