Susan I. Barr

There is limited evidence regarding the potential risk of untargeted iron supplementation, especially among individuals who are iron-replete or have genetic hemoglobinopathies. Excess iron exposure can increase the production of reactive oxygen species, which can lead to cellular damage. We evaluated the effect of daily oral supplementation on relative leukocyte telomere length (rLTL) and blood mitochondrial DNA (mtDNA) content in non-pregnant Cambodian women (18–45 years) who received 60 mg of elemental iron as ferrous sulfate (n = 190) or a placebo (n = 186) for 12 weeks. Buffy coat rLTL and mtDNA content were quantified by monochrome multiplex quantitative polymerase chain reaction. Generalized linear mixed-effects models were used to predict the absolute and percent change in rLTL and mtDNA content after 12 weeks. Iron supplementation was not associated with an absolute or percent change in rLTL after 12 weeks compared with placebo (ß-coefficient: −0.04 [95% CI: −0.16, 0.08]; p = 0.50 and ß-coefficient: −0.96 [95% CI: −2.69, 0.77]; p = 0.28, respectively). However, iron supplementation was associated with a smaller absolute and percent increase in mtDNA content after 12 weeks compared with placebo (ß-coefficient: −11 [95% CI: −20, −2]; p = 0.02 and ß-coefficient: −11 [95% CI: −20, −1]; p= 0.02, respectively). Thus, daily oral iron supplementation for 12 weeks was associated with altered mitochondrial homeostasis in our study sample. More research is needed to understand the risk of iron exposure and the biological consequences of altered mitochondrial homeostasis in order to inform the safety of the current global supplementation policy.

The WHO recommends daily iron supplementation for all women in areas where the population-level anemia prevalence is ≥40%, despite the fact that hemoglobin (Hb) concentration is generally considered to be a poor prognostic indicator of iron status. In this secondary analysis, we investigated the predictive power of ten baseline hematological biomarkers towards a 12-week Hb response to iron supplementation. Data were obtained from a randomized controlled trial of daily iron supplementation in 407 nonpregnant Cambodian women (18–45 years) who received 60 mg elemental iron as ferrous sulfate for 12 weeks. Ten baseline biomarkers were included: Hb, measured with both a hematology analyzer and a HemoCue; inflammation-adjusted ferritin; soluble transferrin receptor; reticulocyte Hb; hepcidin; mean corpuscular volume; inflammation-adjusted total body iron stores (TBIS); total iron binding capacity; and transferrin saturation. Receiver operating characteristic (ROC) curves from fitted logistic regression models were used to make discrimination comparisons and variable selection methods were used to construct a multibiomarker prognostic model. Only 25% (n = 95/383) of women who completed the trial experienced a 12-week Hb response ≥10 g/L. The strongest univariate predictors of a Hb response were Hb as measured with a hematology analyzer, inflammation-adjusted ferritin, hepcidin, and inflammation-adjusted TBIS (AUC^ROC = 0.81, 0.83, 0.82, and 0.82, respectively), and the optimal cutoffs to identify women who were likely to experience a Hb response were 117 g/L, 17.3 μg/L, 1.98 nmol/L, and 1.95 mg/kg, respectively. Hb as measured with a hematology analyzer, inflammation-adjusted ferritin, and hepcidin had the best combined predictive ability (AUC^ROC=0.86). Hb measured with the HemoCue had poor discrimination ability (AUC^ROC = 0.65). Baseline Hb as measured with a hematology analyzer was as strong a predictor of Hb response to iron supplementation as inflammation-adjusted ferritin, hepcidin, and inflammation-adjusted TBIS. This is positive given that the WHO currently uses the population-level anemia prevalence to guide recommendations for untargeted iron supplementation.

Nutrition surveys suggest that 25% of Vancouver's population and are postulated to have poorer riboflavin status than those of European ethnicity because they could be less likely to consume dairy products and fortified wheat. The objectives of this study were to determine dietary riboflavin intake and food sources, and to assess the association between riboflavin intake and status in young women of European (n = 107) and Chinese (n = 91) ethnicities living in Metro Vancouver, Canada. This was a cross-sectional study conducted in women (aged 19–45 y). Women were healthy, not pregnant or breastfeeding, of European or Chinese ethnicities, and not taking riboflavin-containing supplements for the past 4 mo. Dietary riboflavin intake was assessed using the past-year Diet History Questionnaire II, and riboflavin status (EGRac) was measured in fasting venous blood samples. Only 7% of participants had dietary riboflavin intakes below the Estimated Average Requirement (0.9 mg/d), but 40% of women had biochemical riboflavin deficiency (EGRac ≥1.40). Although more Canadian women of European ethnicity than Chinese ethnicity had biochemical riboflavin deficiency (46% and 34%; P < 0.001), median dietary riboflavin intake did not differ (1.73 and 1.82 mg/d; P = 0.587). Dairy products and vegetables contributed the most to riboflavin intake. Energy-adjusted dietary riboflavin intake was inversely associated with EGRac (B = −0.04, 95% CI: −0.07, −0.01). However, after further adjustment the relation was not significant. Overall, women of reproductive age living in Metro Vancouver, Canada, had a low prevalence of inadequate dietary riboflavin intake despite the high prevalence of apparent biochemical riboflavin deficiency.

The authors wish to make a correction to the published version of their paper

This analysis assessed the nutrient content of foods depicted in Canada’s Food Guide Snapshot. Nutrient contents per 2000 kcal were initially assessed by comparison to Daily Values (DVs). For essential nutrients provided in amounts 90%. Novelty Canadians who consume foods as depicted in the Food Guide Snapshot are likely to fall below dietary requirements for calcium and vitamin D.

Background: Multiple micronutrient (MMN) supplementation may result in interaction effects due to competing absorptive pathways of trace elements. Objectives: The aim of this study was to investigate the effect of MMN supplementation with or without iron on serum zinc, selenium, and copper concentrations in Cambodian women. Methods: In a 2 x 2 factorial double-blind randomized 12-wk trial, predominantly anemic, nonpregnant women (aged 18-45 y) received daily 60 mg of iron (Fe; n = 201); 14 other micronutrients including zinc (15 mg), selenium (65 mu g), and copper (2 mg), but no iron (MMN; n = 202); 60 mg iron plus MMN (Fe + MMN; n = 206); or a placebo (n = 200). Fasting morning blood was collected at baseline and 12 wk from women in 26 villages in Kampong Chhnang province. Serum zinc, selenium, and copper concentrations (secondary outcomes of the randomized controlled trial) were measured using inductively coupled plasma mass spectrometry. Generalized linear regression was used to estimate intervention effects [beta coefficient (95% CI)] for Fe (with or without MMN) and MMN (with or without Fe) after testing for the presence of an Fe x MMN interaction. Results: A total of 760 women completed the trial. Zinc deficiency prevalence at baseline was 45% (inflammationadjusted serum zinc < 10.7 mu mol/L). A significant Fe x MMN interaction (P = 0.02) was detected in the 2 x 2 analysis with serum zinc concentration as the outcome: the MMN group had a higher mean serum zinc concentration at 12 wk (12.3 mu mol/L; 95% CI: 12.2, 12.4 mu mol/L) compared with all other groups, and the Fe + MMN group had a higher mean serum zinc concentration (11.6 mu mol/L; 95% CI: 11.5, 11.7 mu mol/L) compared with the Fe group (11.0 mu mol/L; 95% CI: 10.9, 11.0 mu mol/L) and the placebo group (11.2 mu mol/L; 95% CI: 11.1, 11.4 mu mol/L). Conclusions: The inclusion of 60 mg iron in the daily MMN formulation may be interfering with the absorption and/or metabolism of supplemental zinc in Cambodian women. This is of particular concern when MMN supplementation is implemented in populations with risk of zinc deficiency. This trial was registered at clinicaltrials. gov as NCT-02481375.

The International Breakfast Research Initiative (IBRI) set out to derive nutritional recommendations for a balanced breakfast using a standardized analysis of national nutrition surveys from Canada, Denmark, France, Spain, UK and the US. In all countries, the frequency of breakfast consumption by age was high and U-shaped with children and older adults having a higher frequency of breakfast consumption. Breakfast contributed 16% to 21% of daily energy intake. In all countries, breakfast was a carbohydrate- and nutrient-rich meal, providing more carbohydrates (including sugars), thiamin, riboflavin, folate, calcium, potassium, and magnesium, and less vitamin A, fats and sodium relative to its contribution to daily energy intakes. Breakfast consumers were stratified by tertiles of the Nutrient Rich Foods (NRF) index, used as a measure of diet quality. Breakfast intakes associated with the top tertile of NRF, along with the Codex Alimentarius international food standards and World Health Organization (WHO) diet guidelines, were used to derive the proposed nutrient recommendations. The goal was to preserve the nutrient density of existing breakfasts, while addressing concerns regarding added sugars, saturated fats, dietary fiber, and vitamin D. This initiative is unique in seeking to derive nutrient recommendations for a specific meal using the observed nutritional profile of such meal.

Choline, an essential dietary nutrient for humans, is required for the synthesis of the neurotransmitter, acetylcholine, the methyl group donor, betaine, and phospholipids; and therefore, choline is involved in a broad range of critical physiological functions across all stages of the life cycle. The current dietary recommendations for choline have been established as Adequate Intakes (AIs) for total choline; however, dietary choline is present in multiple different forms that are both water-soluble (e.g., free choline, phosphocholine, and glycerophosphocholine) and lipid-soluble (e.g., phosphatidylcholine and sphingomyelin). Interestingly, the different dietary choline forms consumed during infancy differ from those in adulthood. This can be explained by the primary food source, where the majority of choline present in human milk is in the water-soluble form, versus lipid-soluble forms for foods consumed later on. This review summarizes the current knowledge on dietary recommendations and assessment methods, and dietary choline intake from food sources across the life cycle.

This study used 24-h recall data from the nationally representative 2015 Canadian Community Health Survey-Nutrition to assess breakfast intake among Canadians aged 6–12 years (n = 2331), 13–17 years (n = 2026), 18–54 years (n = 7651), and 55+ years (n = 6279). Overall, 90% consumed breakfast; breakfast consumers reported higher intakes of energy and key nutrients and had higher daily diet quality scores assessed using the Nutrient-Rich Foods Index 9.3 (NRF 9.3). Among breakfast consumers (n = 16,484), breakfast contributed a mean of 389 kcal (1628 kJ) and 21.6% of daily energy intake. Relative to its contribution to energy, breakfast contributed higher intakes of fruit, whole grains, and fluid milk, as well as associated nutrients (e.g., carbohydrate, total sugars, fiber, calcium, and vitamin D). Among breakfast consumers classified by daily dietary quality (NRF 9.3 score), energy intake at breakfast did not differ across tertiles for either children or adults. However, intakes of key nutrients, fiber, and total sugars increased across tertiles, and among adults, intakes of saturated fat and sodium decreased. Mean intakes of fruit, whole grains, and fluid milk also increased across tertiles, as did the proportion of individuals consuming these foods; higher fruit and milk intakes may explain higher sugar intakes as diet quality increased. Promoting the consumption of these foods at breakfast could contribute to improved diet quality among Canadians.