An Ex-Ante Analysis of the Impact of Biofortified Zinc Rice on Dietary Zinc Inadequacy: Evidence from Bangladesh, Indonesia, and the Philippines.

BACKGROUND: South, East and Southeast Asia are among regions of the world with the highest estimated prevalence of inadequate zinc intake. Because populations in those regions eat rice as their main staple, zinc biofortification of rice has the potential to improve zinc intake especially among the most vulnerable OBJECTIVE: We modeled the impact of consumption of zinc-biofortified rice on zinc intake and inadequacy among women of childbearing age and young children nationally in Indonesia, and the Philippines, and at a sub-national level in Bangladesh METHODS: We conducted an ex-ante analysis by applying increments of zinc content in rice, from a baseline level of 16 parts per million (ppm) to 100 ppm, and based on rice consumption data to substitute levels of conventional rice with zinc-biofortified rice varying between 10% and 70% RESULTS: Among all datasets evaluated from these three countries, the prevalence of dietary zinc inadequacy at baseline was 94 to 99% among women of childbearing age, 77 to 100% among children 4-5 years old and 27 to 78% among children 1-3 years old. At the current breeding target of 28 ppm, zinc-biofortified rice has the potential to decrease zinc inadequacy by up to 50 percent among women and children in rural Bangladesh and among children in the Philippines where consumption of rice is higher compared to Indonesia CONCLUSIONS: Our analysis shows that increasing zinc content in rice up to 45 ppm reduces the burden of zinc inadequacy substantially, after which we encourage programs to increase coverage to reach the highest number of beneficiaries.

Biofortified Yellow-Fleshed Potatoes Provide More Absorbable Zinc than a Commonly Consumed Variety: A Randomized Trial Using Stable Isotopes in Women in the Peruvian Highlands.

BACKGROUND: Zinc-biofortified potatoes have considerable potential to reduce zinc deficiency because of their low levels of phytate, an inhibitor of zinc absorption, and their high consumption, especially in the Andean region of Peru. OBJECTIVES: The purpose of this study was to measure fractional and total zinc absorption from a test meal of biofortified compared with regular potatoes. METHODS: We undertook a single-blinded randomized crossover study (using 67Zn and 70Zn stable isotopes) in which 37 women consumed 500-g biofortified or regular potatoes twice a day. Urine samples were collected to determine fractional and total zinc absorption. RESULTS: The zinc content of the biofortified potato and regular potato was 0.48 (standard deviation [SD]: 0.02) and 0.32 (SD: 0.03) mg/100 g fresh weight, respectively. Mean fractional zinc absorption (FZA) from the biofortified potatoes was lower than from the regular potatoes, 20.8% (SD: 5.4%) and 25.5% (SD: 7.0%), respectively (P < 0.01). However, total zinc absorbed was significantly higher (0.49; SD: 0.13 and 0.40; SD: 0.11 mg/500 g, P < 0.01, respectively). CONCLUSIONS: The results of this study demonstrate that biofortified potatoes provide more absorbable zinc than regular potatoes. Zinc-biofortified potatoes could contribute toward reducing zinc deficiency in populations where potatoes are a staple food. This trial was registered at clinicaltrials.gov as NCT05154500.

Total Iron Absorbed from Iron-Biofortified Potatoes Is Higher than that from Nonbiofortified Potatoes: A Randomized Trial Using Stable Iron Isotopes in Women from the Peruvian Highlands.

BACKGROUND: Yellow-fleshed potatoes biofortified with iron have been developed through conventional breeding, but the bioavailability of iron is unknown. OBJECTIVES: Our objective was to measure iron absorption from an iron-biofortified yellow-fleshed potato clone in comparison with a nonbiofortified yellow-fleshed potato variety. METHODS: We conducted a single-blinded, randomized, crossover, multiple-meal intervention study. Women (n = 28; mean ± SD plasma ferritin 21.3 ± 3.3 µg/L) consumed 10 meals (460 g) of both potatoes, each meal extrinsically labeled with either 58Fe sulfate (biofortified) or 57Fe sulfate (nonfortified), on consecutive days. Iron absorption was estimated from iron isotopic composition in erythrocytes 14 d after administration of the final meal. RESULTS: Mean ± SD iron, phytic acid, and ascorbic acid concentrations in iron-biofortified and the nonfortified potato meals (mg/per 100 mg) were 0.63 ± 0.01 and 0.31 ± 0.01, 39.34 ± 3.04 and 3.10 ± 1.72, and 7.65 ± 0.34 and 3.74 ± 0.39, respectively (P < 0.01), whereas chlorogenic acid concentrations were 15.14 ± 1.72 and 22.52 ± 3.98, respectively (P < 0.05). Geometric mean (95% CI) fractional iron absorption from the iron-biofortified clone and the nonbiofortified variety were 12.1% (10.3%-14.2%) and 16.6% (14.0%-19.6%), respectively (P < 0.001). Total iron absorption from the iron-biofortified clone and the nonbiofortified variety were 0.35 mg (0.30-0.41 mg) and 0.24 mg (0.20-0.28 mg) per 460 g meal, respectively (P < 0.001). CONCLUSIONS: TIA from iron-biofortified potato meals was 45.8% higher than that from nonbiofortified potato meals, suggesting that iron biofortification of potatoes through conventional breeding is a promising approach to improve iron intake in iron-deficient women. The study was registered at www. CLINICALTRIALS: gov as Identifier number NCT05154500.

FADS1 and FADS2 as biomarkers of Zn status - a systematic review and meta-analysis.

Despite enormous research efforts, a sufficiently sensitive and reliable biomarker for the assessment of zinc (Zn) status has not been identified to date. Zn affects fatty acid metabolism and alters the activity of certain desaturases; thus, desaturase activity has been proposed as a potential new biomarker of Zn status. This systematic review complied and assessed studies that examined changes in fatty acid desaturase 1 (FADS1) and fatty acid desaturase 2 (FADS2) activities in relation to modifications in dietary Zn intake. A systematic search was performed in PubMed, Web of Science, Scopus, Web of Knowledge, and Central with strictly defined search, inclusion, and exclusion criteria. Twenty-one studies were included, 8 animal and 13 human trials (5 randomized controlled trials, two non-randomized controlled trials, and 6 cross-sectional studies). This systematic review was performed using PRISMA guidelines and where feasible a random-effects meta-analysis was conducted. No significant correlation was seen between the delta 6 desaturase and Zn status (-0.0958, 95% CIs (-0.2912; 0.1074), p = 0.2928). Delta 6 desaturase seems to respond in a greater magnitude than Zn status to Zn-containing interventions (the standardized mean difference for delta 6 desaturase was -0.6052, 95% CIs (-2.7162; 1.5058), p = 0.4289, while for plasma/serum Zn it was 0.0319, 95% CIs (-0.9133; 0.9770), p = 0.9213). Finally, two separate meta-analyses on same studies that assessed the correlations between LA:DGLA and Zn intake and Zn status and Zn intake revealed that the magnitude of correlations was only slightly different (the pooled correlation coefficient between the LA:DGLA ratio and Zn intake had a value of -0.1050, 95% CIs (-0.5356; 0.3690), p = 0.454, while between plasma Zn and Zn intake had a value of -0.0647, 95% CIs (-0.4224; 0.3106), p = 0.5453). According to the descriptive analysis, the magnitude of variation in desaturase activities in response to Zn intake was not consistent among studies, FADS1 and FADS2 activity corresponded to dietary Zn manipulations, both in animals and humans. A plausible explanation for this observation might be the difference between the studies in study populations, types of dietary interventions, study durations, etc. In addition, several potential confounders and covariates are identified from the qualitative synthesis, such as gender, age, the type of fat provided within the dietary intervention, the size of Zn particles, among others. Further high-quality studies are needed to additionally clarify the suggested associations and applicability of utilizing fatty acid desaturase activities as Zn status biomarkers.

Bioaccessibility and bioavailability of biofortified food and food products: Current evidence.

Biofortification increases micronutrient content in staple crops through conventional breeding, agronomic methods, or genetic engineering. Bioaccessibility is a prerequisite for a nutrient to fulfill a biological function, e.g., to be bioavailable. The objective of this systematic review is to examine the bioavailability (and bioaccessibility as a proxy via in vitro and animal models) of the target micronutrients enriched in conventionally biofortified crops that have undergone post-harvest storage and/or processing, which has not been systematically reviewed previously, to our knowledge. We searched for articles indexed in MEDLINE, Agricola, AgEcon, and Center for Agriculture and Biosciences International databases, organizational websites, and hand-searched studies' reference lists to identify 18 studies reporting on bioaccessibility and 58 studies on bioavailability. Conventionally bred biofortified crops overall had higher bioaccessibility and bioavailability than their conventional counterparts, which generally provide more absorbed micronutrient on a fixed ration basis. However, these estimates depended on exact cultivar, processing method, context (crop measured alone or as part of a composite meal), and experimental method used. Measuring bioaccessibility and bioavailability of target micronutrients in biofortified and conventional foods is critical to optimize nutrient availability and absorption, ultimately to improve programs targeting micronutrient deficiency.

Modeling relationships between iron status, behavior, and brain electrophysiology: evidence from a randomized study involving a biofortified grain in Indian adolescents.

BACKGROUND: Iron deficiency (ID) and iron deficiency anemia (IDA) are highly-prevalent nutrient deficiencies and have been shown to have a range of negative effects on cognition and brain function. Human intervention studies including measures at three levels-blood, brain, and behavior-are rare and our objective was to model the relationships among measures at these three levels in school-going Indian adolescents. METHODS: Male and female adolescents in rural India were screened for ID/IDA. Subjects consumed 2 meals/day for 6 months; half were randomly assigned to consume meals made from a standard grain (pearl millet) and half consumed meals made from an iron biofortified pearl millet (BPM). Prior to and then at the conclusion of the feeding trial, they completed a set of cognitive tests with concurrent electroencephalography (EEG). RESULTS: Overall, serum ferritin (sFt) levels improved over the course of the study. Ten of 21 possible measures of cognition showed improvements from baseline (BL) to endline (EL) that were larger for those consuming BPM than for those consuming the comparison pearl millet (CPM). Critically, the best model for the relationship between change in iron status and change in cognition had change in brain measures as a mediating factor, with both change in serum ferritin as a primary predictor and change in hemoglobin as a moderator. CONCLUSIONS: A dietary intervention involving a biofortified staple grain was shown to be efficacious in improving blood iron biomarkers, behavioral measures of cognition, and EEG measures of brain function. Modeling the relationships among these variables strongly suggests multiple mechanisms by which blood iron level affects brain function and cognition. TRIAL REGISTRATION: Registered at ClinicalTrials.gov, NCT02152150 , 02 June 2014.

Changes in Iron Status Are Related to Changes in Brain Activity and Behavior in Rwandan Female University Students: Results from a Randomized Controlled Efficacy Trial Involving Iron-Biofortified Beans.

BACKGROUND: Evidence suggests that iron deficiency (ID) affects cognitive performance, as measured in behavior. Although such effects must be mediated by changes in the brain, very few studies have included measures of brain activity to assess this relation. OBJECTIVE: We tested the hypothesis that provision of iron-biofortified beans would result in improvements in measures of iron status, brain dynamics, and behavior. METHODS: A double-blind, randomized, intervention study was conducted in 55 women aged 18-27 y with low iron status (serum ferritin <20 µg/L). Women were randomly assigned to consume iron-biofortified (86.1 ppm iron) or comparison beans (50.1 ppm iron) daily for 18 wk. Iron status was assessed by hemoglobin, ferritin, transferrin receptor, and body iron; cognitive performance with 5 computerized tasks; and brain dynamics by concurrent electroencephalography (EEG). All measures were taken at baseline and endline. RESULTS: The groups did not differ on any measures at baseline. Intention-to-treat analyses revealed significant (all P < 0.05) improvements in hemoglobin (partial effect size attributable to the independent variable, η2 = 0.16), ferritin (η2 = 0.17), and body iron (η2 = 0.10), speed of responding in attentional and mnemonic tasks (η2 = 0.04-0.29), sensitivity and efficiency of memory retrieval (η2 = 0.12-0.55), and measures of EEG amplitude and spectral power (η2 = 0.08 to 0.49). Mediation models provided evidence in support of the hypothesis that changes in iron status produce changes in behavior by way of changes in brain activity. CONCLUSIONS: Behavioral performance and brain activity, as measured by EEG, are sensitive to iron status, and the consumption of iron-biofortified beans for 18 wk resulted in improvements in measures of both, relative to what was obtained with a comparison bean, in a sample of female university students. Furthermore, the results support the conclusion that changes in brain activity resulting from consumption of biofortified beans mediate the relations between changes in iron biomarkers and changes in cognition. Clinical trial registry: ClinicalTrials.gov Reg No. NCT01594359.

Zinc Absorption From Agronomically Biofortified Wheat Is Similar to Post-Harvest Fortified Wheat and Is a Substantial Source of Bioavailable Zinc in Humans.

BACKGROUND: Limited data exist on human zinc absorption from wheat biofortified via foliar (FBW) or root (hydroponically fortified wheat, HBW) zinc application. Stable isotope labels added at point of consumption (extrinsic labeling) might not reflect absorption from native zinc obtained by intrinsic labeling. OBJECTIVES: We measured fractional and total zinc absorption (FAZ, TAZ) in FBW and HBW wheat, compared with control wheat (CW) and fortified wheat (FW). The effect of labeling method was assessed in HBW (study 1), and the effect of milling extraction rate (EXR, 80% and 100%) in FBW (studies 2 and 3). METHODS: Generally healthy adults (n = 71, age: 18-45 y, body mass index: 18.5-25 kg/m2) were allocated to 1 of the studies, in which they served as their own controls. In study 1, men and women consumed wheat porridges colabeled intrinsically and extrinsically with 67Zn and 70Zn. In studies 2 and 3, women consumed wheat flatbreads (chapatis) labeled extrinsically. Zinc absorption was measured with the oral to intravenous tracer ratio method with a 4-wk wash-out period between meals. Data were analyzed with linear mixed models. RESULTS: In study 1 there were no differences in zinc absorption from extrinsic versus intrinsic labels in either FW or HBW. Similarly, FAZ and TAZ from FW and HBW did not differ. TAZ was 70-76% higher in FW and HBW compared with CW (P < 0.01). In studies 2 and 3, TAZ from FW and FBW did not differ but was 20-48% higher compared with CW (P < 0.001). Extraction rate had no effect on TAZ. CONCLUSIONS: Colabeling demonstrates that extrinsic zinc isotopic labels can be used to accurately quantify zinc absorption from wheat in humans. Biofortification through foliar zinc application, root zinc application, or fortification provides higher TAZ compared with unfortified wheat. In biofortified wheat, extraction rate (100-80%) has a limited impact on total zinc absorption. These studies were registered on clinicaltrials.gov (NCT01775319).

Cognitive Performance in Indian School-Going Adolescents Is Positively Affected by Consumption of Iron-Biofortified Pearl Millet: A 6-Month Randomized Controlled Efficacy Trial.

BACKGROUND: Iron deficiency remains the most prevalent micronutrient deficiency globally, but few studies have examined how iron status relates to cognition in adolescents. Iron biofortification of staple food crops is being scaled up, yet it is unknown whether consuming biofortified crops can benefit cognition. Objective: Our objective was to determine the efficacy of iron-biofortified pearl millet in improving attention and memory in Indian school-going adolescents. Methods: A double-blind, randomized, intervention study was conducted in 140 Indian boys and girls, aged 12-16 y, who were assigned to consume iron-biofortified [Fe = 86 parts per million (ppm)] or conventional (Fe = 21-52 ppm) pearl millet. Hemoglobin, ferritin, and transferrin receptor (TfR) were measured and body iron (BI) was calculated at baseline and after 4 and 6 mo. Five measures of cognitive function were obtained at baseline and 6 mo: simple reaction time (SRT), Go/No-Go (GNG) task, Attentional Network Task (ANT), Composite Face Effect (CFE) task, and Cued Recognition Task (CRT). Intention-to-treat analysis was used. Results: Daily iron intake from pearl millet was higher in those consuming biofortified compared with conventional pearl millet (19.6 compared with 4.8 mg/d). Effects on ferritin, TfR, and BI at 4 mo, and on TfR at 6 mo (all P < 0.05), indicated efficacy of biofortified pearl millet over conventional pearl millet in improving iron status. Compared with conventional pearl millet, the consumption of biofortified pearl millet resulted in greater improvement in attention (SRT, GNG, and ANT) and memory (CFE and CRT). Reaction time decreased twice as much from 0 to 6 mo in those consuming biofortified compared with conventional pearl millet on attention tasks (SRT: -123 compared with -63 ms; GNG: -67 compared with -30 ms; ANT double cue: -74 compared with -32 ms; all P < 0.01). Conclusion: Consuming iron-biofortified pearl millet improves iron status and some measures of cognitive performance in Indian adolescents. This trial was registered at http://www.clinicaltrials.gov as NCT02152150.

Serum Soluble Transferrin Receptor Concentrations Are Elevated in Congolese Children with Glucose-6-Phosphate Dehydrogenase Variants, but Not Sickle Cell Variants or α-Thalassemia.

Background: Anemia is common in Congolese children, and inherited blood disorders may be a contributing cause. The presence of sickle cell variants, X-linked glucose-6-phosphate dehydrogenase (G6PD) deficiency and α-thalassemia, has been previously reported. G6PD A- deficiency is characterized by the co-inheritance of G6PD 376 and 202 variants and is common in sub-Saharan Africa.Objective: We aimed to measure the associations between inherited blood disorders and hemoglobin, ferritin, and soluble transferrin receptor (sTfR) concentrations in Congolese children.Methods: Venous blood was collected from 744 children aged 6-59 mo from 2 provinces. We measured biomarkers of nutritional and inflammation status and malaria. Pyrosequencing was used to detect sickle cell variants. Polymerase chain reaction was used to detect G6PD variants and α-thalassemia deletions.Results: Overall, 11% of children had a sickle cell variant, 19% of boys were G6PD A- hemizygotes, 12% and 10% of girls were G6PD A- hetero- or homozygotes, respectively, and 12% of children had α-thalassemia. Multivariable linear regression models (adjusted for age, province, altitude, malaria, and biomarkers of nutritional and inflammation status) showed that G6PD A- hemizygous boys and G6PD 376 homozygous girls had higher sTfR concentrations [geometric mean ratios (95% CIs): 1.20 (1.03, 1.39) and 1.25 (1.02, 1.53), respectively] than children with no G6PD variants. Hemoglobin and ferritin concentrations were not independently associated with any of the inherited blood disorder genotypes.Conclusions: We found that 2 G6PD variant genotypes were associated with elevated sTfR concentrations, which limits the accuracy of sTfR as a biomarker of iron status in this population.

Comparison of four immunoassays to measure serum ferritin concentrations and iron deficiency prevalence among non-pregnant Cambodian women and Congolese children.

BACKGROUND: Global standardization of ferritin assays is lacking, which could have direct implications on the accurate measurement and comparability of ferritin concentration and iron deficiency (ID) prevalence rates in at-risk populations. METHODS: We measured serum ferritin concentrations using four immunoassays: the s-ELISA and the AxSYM™ analyzer were compared among 420 non-pregnant Cambodian women; the Centaur® XP analyzer, s-ELISA, and AxSYM™ analyzer were compared among a subset of 100 Cambodian women; and the s-ELISA and the Elecsys® 2010 analyzer were compared among 226 Congolese children aged 6-59 months. RESULTS: Median ferritin concentrations (adjusted for inflammation) ranged between 48 and 91 µg/L among Cambodian women and between 54 and 55 µg/L among Congolese children. ID prevalence ranged from 2% to 10% among Cambodian women and 5% to 7% among Congolese children. Bias between methods varied widely (-9 to 45 µg/L) among women, and was 43 µg/L among children. Bias was lower when ferritin values outside of the s-ELISA measurement range (>250 µg/L) were excluded. CONCLUSIONS: The observed differences in ferritin concentrations likely reflect different ferritin isoforms, antibodies, and calibrators used across assays and by different laboratories. However, despite differences in ferritin concentrations, ID prevalence was relatively similar and low across all methods.

Nutritional Status and Physical Fitness of Tribal Adolescents in Ahmednagar District of Maharashtra.

We examined the influence of nutritional status, body fat, and anemia on the physical fitness (PFI) of tribal adolescents. Weight, height, skinfold thickness, PFI, and hemoglobin levels of 147 adolescents (11 to 16 years) were measured. The experience of cycling was recorded. Overall, 31.3% were mildly, 12.9% were moderately, and 10.9% were severely thin. The majority (81.6%) were nonanemic. All had "poor" PFI scores. Hemoglobin levels were significantly associated with PFI scores in boys and girls. Experience of cycling also predicted PFI in girls. Nutritional status, hemoglobin level, and physical activity were associated with the fitness levels of these adolescents.

In Rwandese Women with Low Iron Status, Iron Absorption from Low-Phytic Acid Beans and Biofortified Beans Is Comparable, but Low-Phytic Acid Beans Cause Adverse Gastrointestinal Symptoms.

BACKGROUND: Phytic acid (PA) is a major inhibitor of iron bioavailability from beans, and high PA concentrations might limit the positive effect of biofortified beans (BBs) on iron status. Low-phytic acid (lpa) bean varieties could increase iron bioavailability. OBJECTIVE: We set out to test whether lpa beans provide more bioavailable iron than a BB variety when served as part of a composite meal in a bean-consuming population with low iron status. METHODS: Dietary iron absorption from lpa, iron-biofortified, and control beans (CBs) (regular iron and PA concentrations) was compared in 25 nonpregnant young women with low iron status with the use of a multiple-meal crossover design. Iron absorption was measured with stable iron isotopes. RESULTS: PA concentration in lpa beans was ∼10% of BBs and CBs, and iron concentration in BBs was ∼2- and 1.5-fold compared with CBs and lpa beans, respectively. Fractional iron absorption from lpa beans [8.6% (95% CI: 4.8%, 15.5%)], BBs [7.3% (95% CI: 4.0%, 13.4%)], and CBs [8.0% (95% CI: 4.4%, 14.6%)] did not significantly differ. The total amount of iron absorbed from lpa beans and BBs was 421 µg (95% CI: 234, 756 µg) and 431 µg (95% CI: 237, 786 µg), respectively, and did not significantly differ, but was >50% higher (P < 0.005) than from CBs (278 µg; 95% CI: 150, 499 µg). In our trial, the lpa beans were hard to cook, and their consumption caused transient adverse digestive side effects in ∼95% of participants. Gel electrophoresis analysis showed phytohemagglutinin L (PHA-L) residues in cooked lpa beans. CONCLUSION: BBs and lpa beans provided more bioavailable iron than control beans and could reduce dietary iron deficiency. Digestive side effects of lpa beans were likely caused by PHA-L, but it is unclear to what extent the associated digestive problems reduced iron bioavailability. This trial was registered at clinicaltrials.gov as NCT02215278.

Regular Consumption of a High-Phytate Diet Reduces the Inhibitory Effect of Phytate on Nonheme-Iron Absorption in Women with Suboptimal Iron Stores.

BACKGROUND: High phytate (HP) consumption is a concern in developing countries because of the high prevalence of iron deficiency in these countries. OBJECTIVE: We investigated whether habitual consumption of an HP diet reduces the inhibitory effect of phytate on nonheme-iron absorption. METHODS: Thirty-two nonanemic females, 18-35 y of age, with normal body mass index but with suboptimal iron stores (serum ferritin, ≤30 µg/L), were matched for serum ferritin concentration and randomly assigned to HP and low-phytate (LP) groups, in a parallel design study. Each subject consumed HP or LP foods with at least 2 of their daily meals for 8 wk, resulting in a change in phytate intake (from 718 to 1190 mg/d in the HP group and 623 to 385 mg/d in the LP group). The serum iron response over 4 h after a test meal containing 350 mg of phytate was measured at baseline and postintervention. Ferritin, transferrin receptor, and hepcidin concentrations were measured at baseline and 8 wk. RESULTS: Twenty-eight subjects completed the study (n = 14 per group). The serum iron response to the test meal increased in the HP group at postintervention, resulting in a 41% increase in the area under the curve (AUC; P < 0.0001). However, no effect was observed in the LP group (21% decrease in AUC; P = 0.76). The postintervention serum iron response was lower (P < 0.0001) in the LP group than in the HP group after controlling for the baseline serum iron response and hepcidin concentration, reflecting in a 64% lower AUC. CONCLUSIONS: We found that habitual consumption of an HP diet can reduce the negative effect of phytate on nonheme-iron absorption among young women with suboptimal iron stores. Future studies are needed to explore possible mechanisms. This trial was registered at clinicaltrials.gov as NCT02370940.

Retention of provitamin a carotenoids in staple crops targeted for biofortification in Africa: cassava, maize and sweet potato.

HarvestPlus, part of the Consultative Group on Internation Agriculture research (CGIAR) Program on Agriculture for Nutrition and Health (A4NH) uses conventional plant breeding techniques to develop staple food crops that are rich in micronutrients, a food-based approach to reduce micronutrient malnutrition known as biofortification. The nutritional breeding targets are established based on the food intake of target populations, nutrient losses during storage and processing and bioavailability. This review collates the evidence on the retention of provitamin A carotenoid (pVAC) after processing, cooking, and storing of the staple crops targeted for pVAC biofortification: cassava, maize, and sweet potato. Sun drying was more detrimental to the pVAC levels (27-56% retention) in cassava than shade (59%) or oven (55-91%) drying, while the pVAC retention levels (66-96%) in sweet potato were not significantly different among the various drying methods. Overall, boiling and steaming had higher pVAC retention (80-98%) compared to baking (30-70%) and frying (18-54%). Gari, the most frequently consumed form of cassava in West Africa had the lowest pVAC retention (10-30%). The pVAC retention of maize grain and cassava and sweet potato flour reached levels as low as 20% after 1-4 months of storage and was highly dependent on genotype. Therefore, we recommend that an evaluation of the pVAC degradation rate among different genotypes be performed before a high pVAC crop is promoted.

Folate status and intake of tribal Indian adolescents aged 10 to 17 years.

BACKGROUND: Adequate folate intake and levels are advisable throughout life but are of particular importance during adolescence, a period of rapid growth. However, folate insufficiency in economically deprived Indian adolescents is understudied. OBJECTIVE: This cross-sectional study examined the prevalence of folate deficiency and adequacy of folate intake of 224 tribal Indian adolescents (10 to 17 years of age). The secondary aim was to study the association between anemia status and folate status. METHODS: Radioimmunoassay, multiple-pass 24-hour dietary recall, and HemoCue were used to measure red blood cell (RBC) folate, folate intake, and anemia status, respectively. RESULTS: The geometric mean (95% CI) RBC folate concentration (nmol/L) was 360.2 (329.7 to 393.6), and the mean ± SD folate intake (µg/day) and hemoglobin level (g/L) were 159.9 ± 44.7 and 125.4 ± 13.0, respectively. Almost half of boys and girls aged 10 to 12 and 13 to 15 years and 66.7% of girls aged 16 to 17 years were deficient in RBCfolate (< 340 nmol/L). The mean ± SD folate intake (µg/day) of girls (139.4 ± 34.5) was lower than that of boys (173.8 ± 45.5) (p < .001). With respect to adequacy of folate intake, a greater proportion of girls in the age group of 13-15 years (78.5% vs 38.6%, p < 0.001) and 16-17 years (100.0% vs 76.9%, p = 0.04) had intakes below their Recommended Dietary Allowance (RDA). No association was observed between folate intake and RBC folate deficiency or between anemia status and RBC folate deficiency. CONCLUSIONS: Folate insufficiency was widespread in tribal Indian adolescents. There is an urgent need to develop culturally sensitive strategies for improvement.

Phytic acid concentration influences iron bioavailability from biofortified beans in Rwandese women with low iron status.

BACKGROUND: The common bean is a staple crop in many African and Latin American countries and is the focus of biofortification initiatives. Bean iron concentration has been doubled by selective plant breeding, but the additional iron is reported to be of low bioavailability, most likely due to high phytic acid (PA) concentrations. OBJECTIVE: The present study evaluated the impact of PA on iron bioavailability from iron-biofortified beans. METHODS: Iron absorption, based on erythrocyte incorporation of stable iron isotopes, was measured in 22 Rwandese women who consumed multiple, composite bean meals with potatoes or rice in a crossover design. Iron absorption from meals containing biofortified beans (8.8 mg Fe, 1320 mg PA/100 g) and control beans (5.4 mg Fe, 980 mg PA/100 g) was measured with beans containing either their native PA concentration or with beans that were ∼50% dephytinized or >95% dephytinized. RESULTS: The iron concentration of the cooked composite meals with biofortified beans was 54% higher than in the same meals with control beans. With native PA concentrations, fractional iron absorption from the control bean meals was 9.2%, 30% higher than that from the biofortified bean meals (P < 0.001). The quantity of iron absorbed from the biofortified bean meals (406 µg) was 19% higher (P < 0.05) than that from the control bean meals. With ∼50% and >95% dephytinization, the quantity of iron absorbed from the biofortified bean meals increased to 599 and 746 µg, respectively, which was 37% (P < 0.005) and 51% (P < 0.0001) higher than from the control bean meals. CONCLUSIONS: PA strongly decreases iron bioavailability from iron-biofortified beans, and a high PA concentration is an important impediment to the optimal effectiveness of bean iron biofortification. Plant breeders should focus on lowering the PA concentration of high-iron beans. This trial was registered at clinicaltrials.gov as NCT01521273.

Preventing and Controlling Zinc Deficiency Across the Life Course: A Call to Action.

Through diverse roles, zinc determines a greater number of critical life functions than any other single micronutrient. Beyond the well-recognized importance of zinc for child growth and resistance to infections, zinc has numerous specific roles covering the regulation of glucose metabolism, and growing evidence links zinc deficiency with increased risk of diabetes and cardiometabolic disorders. Zinc nutriture is, thus, vitally important to health across the life course. Zinc deficiency is also one of the most common forms of micronutrient malnutrition globally. A clearer estimate of the burden of health disparity attributable to zinc deficiency in adulthood and later life emerges when accounting for its contribution to global elevated fasting blood glucose and related noncommunicable diseases (NCDs). Yet progress attenuating its prevalence has been limited due, in part, to the lack of sensitive and specific methods to assess human zinc status. This narrative review covers recent developments in our understanding of zinc's role in health, the impact of the changing climate and global context on zinc intake, novel functional biomarkers showing promise for monitoring population-level interventions, and solutions for improving population zinc intake. It aims to spur on implementation of evidence-based interventions for preventing and controlling zinc deficiency across the life course. Increasing zinc intake and combating global zinc deficiency requires context-specific strategies and a combination of complementary, evidence-based interventions, including supplementation, food fortification, and food and agricultural solutions such as biofortification, alongside efforts to improve zinc bioavailability. Enhancing dietary zinc content and bioavailability through zinc biofortification is an inclusive nutrition solution that can benefit the most vulnerable individuals and populations affected by inadequate diets to the greatest extent.

The global burden of high fasting plasma glucose associated with zinc deficiency: Results of a systematic review and meta-analysis.

Non-communicable diseases (NCDs) account for the largest share of the global disease burden, and increasing evidence shows that zinc deficiency (ZD) contributes to NCDs by inducing oxidative stress, insulin resistance, and impaired lipid metabolism. A systematic review and meta-analysis was conducted to determine whether ZD was associated with fasting plasma glucose (FPG), a key risk factor for NCDs. A random effects meta-analysis was conducted to determine the strength of the association in the form of an odds ratio (OR) and subsequently the population attributable risk (PAR) with population prevalences of high FPG. The disease burden from high FPG attributable to ZD was expressed as disability adjusted life years (DALYS). Data from seven studies were obtained as part of the systematic review. The meta-analysis shows a significant (p<0.01) inverse relationship between ZD and high FPG (OR = 2.34; 95% CI: 1.16, 4.72). Globally, the PAR of ZD's contribution to high FPG is 6.7%, with approximately 8.2 million high FPG DALYs attributable to ZD. Cardiovascular diseases, diabetes, and chronic kidney diseases account for more than 90% of the total DALYs. Total DALYs attributable to ZD are largest in the "Southeast Asia, East Asia, and Oceania" and "High Income" Super Regions. While the disease burden is highest among populous countries (e.g., China, India, USA), the population-standardized DALYs are highest among island nations, particularly island nations in the South Pacific and Caribbean. While ZD accounts for a small share of the high FPG disease burden, the total number of DALYs far surpasses other estimates of the disease burden attributable to ZD, which focus on diarrheal diseases in childhood. Zinc interventions are urgently needed to help address the increasing disease burden from NCDs, and the double burden of malnutrition.