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Background: In Canada, nutrition policy, as outlined in the Nutrition for Healthy Term Infants recommendations, includes a daily vitamin D supplement of 10 μg (400 IU) for breastfed infants and young children to support adequate vitamin D status., Objectives: This study aimed to report on adherence to vitamin D supplementation recommendations for breastfed infants (≤12 months); and for children breastfed >12 mo., Methods: Canadian Community Health Survey (paired-cycles 2015/2016 and 2017/2018) maternal experiences data for infants born 2012-2018 who received any breastmilk formed the sample (n = 7079). Whether the infant was given a vitamin D supplement (yes/no) and the frequency (daily/almost every day, 1-2/wk, or <1/wk) were surveyed. Weighted data (95% CI) were summarized according to breastfeeding history (exclusive to 6 mo and continuing; partial to 6 mo and continuing; and stopped ≤6 mo). Correlates of supplement adherence were explored using logistic regression., Results: Overall, 87.1% (95% CI: 85.9%, 88.3%) of participants reported giving their infant (≤12 mo) a vitamin D supplement, and of these, 83.3% (95% CI: 81.9%, 84.7%) did so daily/almost every day, 12.4% (95% CI: 11.1%, 13.7%) did so 1-2/wk, and 4.3% (95% CI: 3.6%, 5.0%) did so <1/wk. Lower adjusted odds of adherence were observed among participants reporting: stopped breastfeeding ≤6 mo, lower education or income, recent immigration, and overweight prepregnancy body mass index; higher odds of adherence were observed in the western provinces. Regarding mothers of children >12 mo and breastfed (n = 2312), 58.0% (95% CI: 54.9%, 61.1%) gave a vitamin D supplement daily/almost every day., Conclusions: Adherence to providing a vitamin D supplement to breastfed infants is high in Canada. Nonetheless, we estimate that ∼27% of mothers are nonadherent to daily/almost every day administration of a vitamin D supplement and that adherence declines in children breastfed >12 mo. Further promotion to support uptake of the current guidance may be necessary, particularly for parents of recent immigration or lower socioeconomic status., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

l-lysine (Lys) is an essential amino acid that is added to foods and dietary supplements. Lys may interact with mineral nutrients and affect their metabolism. This study examined the effect of dietary Lys supplementation on the bioavailability of copper (Cu) and iron (Fe). Weanling male Sprague-Dawley rats were fed one of five diets (20% casein) for 4 weeks containing normal Cu and Fe (control) or low Cu or Fe without (LCu, LFe) or with (LCu+Lys, LFe+Lys) addition of 1.5% Lys. Final body weights, body weight gains and food consumption of the rats did not differ (P≥0.05) among diet groups. Rats fed the low Cu or Fe diets showed changes in nutritional biomarkers compared to control rats, demonstrating reduced Cu and Fe status, respectively. Hematological parameters, serum ceruloplasmin activity and Cu and Fe concentrations in serum, liver, kidney and intestinal mucosa were unaffected (P≥0.05) by Lys supplementation. These results indicate that in the context of an adequate protein diet, Lys supplementation at a relatively high level does not affect Cu or Fe bioavailability in rats., (Crown Copyright © 2016. Published by Elsevier GmbH. All rights reserved.)

A large section of the North American population is not meeting recommended intakes for magnesium (Mg). Supplementation and consumption of Mg-fortified foods are ways to increase intake. Currently, information on Mg bioavailability from different compounds and their efficacy in improving Mg status is scant. This study compared the relative ability of inorganic and organic Mg compounds to preserve the Mg status of rats when fed at amounts insufficient to retain optimal Mg status. Male Sprague-Dawley rats (n=12/diet group) were fed one of eight test diets supplemented with phytic acid (5 g/kg diet) and low levels of Mg (155 mg elemental Mg/kg diet) from Mg oxide, Mg sulphate, Mg chloride, Mg citrate, Mg gluconate, Mg orotate, Mg malate or ethylenediaminetetraacetic acid disodium Mg salt for five weeks. Rats were also fed three control diets that did not contain added phytic acid but were supplemented with 500 (NMgO, normal), 155 (LMgO, low) or 80 (DMgO, deficient) mg of Mg per kg diet as Mg oxide. Mg concentrations in femur, serum and urine showed a graded decrease in rats fed the control diets with lower Mg. Mg concentrations did not differ (P≥0.05) between rats fed the different test diets. Addition of phytic acid to the diet did not affect the Mg status of the rats. The results indicate that any differences in the Mg bioavailability of the compounds were small and physiologically irrelevant.

The tolerable upper intake levels (UL) for zinc for children were based on limited data and there is concern that the UL may be set too low. The first effect of excessive zinc intake is a reduction in copper status. The primary objective of this study was to examine the effect of zinc supplementation on copper status in children. Healthy, 6- to 8-y-old boys from Ontario, Canada were assigned to take a placebo (n = 10) or 5 mg (n = 10), 10 mg (n = 9), or 15 mg (n = 8) of zinc supplement daily for 4 mo in a double-blinded, placebo-controlled, randomized trial. Biochemical measures were evaluated at baseline and after 2 and 4 mo of supplementation. Food records were completed near the baseline and 4-mo visits. Age and anthropometric measurements did not differ (P > 0.05) between treatment groups at baseline. Mean zinc intakes from food alone (10.9-14.8 mg zinc/d) approached or exceeded the UL of 12 mg/d. Compared with the placebo group, the zinc groups had a greater change in the urine zinc:creatinine ratio at 4 mo (P = 0.02). Traditional (plasma copper and ceruloplasmin activity) and more sensitive biomarkers of copper status, including erythrocyte SOD1 activity and the erythrocyte CCS:SOD1 protein ratio, were unchanged in zinc-supplemented boys, demonstrating that copper status was not depressed. Serum lipid measures and hemoglobin concentrations were also unaffected and gastrointestinal symptoms were not reported. These data provide evidence in support of the need for reexamining the current UL for zinc for children.

Single amino acid (AA) supplementations in foods are increasing, however their potential nutritional and physiological impacts are not fully understood. This study examined the effects of l-lysine (Lys) supplementation on protein quality of diets, serum AA concentrations and associations between the ratio of supplemental Lys to dietary protein (X) with body weight gain (BWG) in Sprague–Dawley male rats. Rats were fed one of 10 diets containing either 7% or 20% casein and supplemented with 0% (Control), 1.5%, 3%, 6% Lys or 6% Lys + 3% l-arginine (Arg) (8 rats/diet group) for 1 week. Lys supplementation reduced the protein quality of the casein-based diets (p < 0.01). BWG was reduced by supplemental Lys when X > 0.18. Free Lys supplementation dose-dependently increased serum Lys levels (p < 0.01), while increased protein-bound Lys (1.4% vs 0.52%) had little effect on serum Lys (p > 0.05). In the 7% casein diets, ≥ 1.5% supplemental Lys reduced serum alanine, asparagine, glycine, isoleucine, leucine, serine, tyrosine, valine, carnitine, ornithine, and increased urea. Supplementation of ≥ 3% Lys additionally reduced tryptophan and increased histidine, methionine and α-aminoadipic acid (α-AAA) compared to the Control (p < 0.05). In the 20% casein diets, addition of ≥ 1.5% Lys reduced serum asparagine and threonine, and ≥ 3% Lys reduced leucine, proline, tryptophan, valine, and ornithine, and 6% Lys reduced carnitine, and increased histidine, methionine, and α-AAA. Overall, this study showed that free Lys supplementation in a Lys-sufficient diet reduced the protein quality of the diets and modified the serum concentrations of many amino acids. Excess free Lys intake adversely affected growth and utilization of nutrients due to AA imbalance or antagonism. Overall lower protein intake increases susceptibility to the adverse effects of Lys supplementation. [ABSTRACT FROM AUTHOR]

Background: Most pregnant or lactating women in Canada will not meet iodine requirements without iodine supplementation.Objectives: To assess the iodine status of 132 mother-infant pairs based on secondary analyses of a vitamin D supplementation trial in breastfed infants from Montréal, Canada.Methods: Maternal iodine status was assessed using the breastmilk iodine concentration (BMIC). Singleton, term-born infants were studied from 1-36 months of age. Usual (adjusted for within-person variation) iodine intakes were estimated from urinary iodine and creatinine concentrations. Iodine status was assessed using median urinary iodine concentrations (UICs) and by estimating inadequate intakes by the cut-point method using a proposed Estimated Average Requirement for infants 0-6 months of age (72 μg/d).Results: At 1, 3, and 6 months of age, 70%, 63%, and 3% of infants, respectively, were exclusively breastfed. From 1-36 months of age (n = 82-129), the median UICs were ≥100 μg/L (range, 246-403 μg/L), which is the cutoff for adequate intakes set by the WHO for children <2 years. Almost all (98%-99%) infants at 1 and 2 months, 2 and 3 months, and 3 and 6 months of age had usual creatinine-adjusted iodine intakes ≥ 72 μg/d. The median BMIC was higher (P < 0.001) at 1 month compared to 6 months of lactation [1 month, 198 μg/kg (IQR, 124-274; n = 105) and 6 months, 109 μg/kg (IQR, 67-168; n = 78)]. At 1 and 6 months, 96% and 79% of mothers, respectively, had a BMIC ≥ 60 μg/kg, the lower limit of a normal reference range. The percentages of mothers that used a multivitamin-mineral (MVM) supplement containing iodine were 90% in pregnancy and 79% and 59% at 1 and 6 months of lactation, respectively.Conclusions: The iodine status of infants was adequate throughout infancy. These results support a recommendation that all women who could become pregnant, who are pregnant, or who are breastfeeding take a daily MVM supplement containing iodine. [ABSTRACT FROM AUTHOR]

Calcium (Ca) intakes may affect cardiovascular disease risk by altering body composition (body weight and fat) and serum lipid profile, but results have been inconsistent and the underlying mechanisms are not well understood. The effects of dietary Ca on body composition and lipid metabolism were examined in rats. Male Sprague-Dawley rats were fed high-fat, high-energy diets containing (g/kg) low (0.75Ca, 0.86 ± 0.05; 2Ca, 2.26 ± 0.02), normal (5Ca, 5.55 ± 0.08) or high (10Ca, 11.03 ± 0.17; 20Ca, 21.79 ± 0.15) Ca for 10 weeks. Rats fed the lowest Ca diet (0.75Ca) had lower (p < 0.05) body weight and fat mass compared to other groups. Rats fed the high Ca diets had lower serum total and LDL cholesterol compared to rats fed normal or low Ca. Liver total cholesterol was lower in rats fed high compared to low Ca. In general, liver mRNA expression of genes involved in cholesterol uptake from the circulation (Ldlr), cholesterol synthesis (Hmgcr and Hmgcs1), fatty acid oxidation (Cpt2) and cholesterol esterification (Acat2) were higher in rats fed higher Ca. Apparent digestibility of total trans, saturated, monounsaturated and polyunsaturated fatty acids was lower in rats fed the high compared to the low Ca diets, with the largest effects seen on trans and saturated fatty acids. Fecal excretion of cholesterol and total bile acids was highest in rats fed the highest Ca diet (20Ca). The results suggest little effect of dietary Ca on body composition unless Ca intakes are very low. Decreased bile acid reabsorption and reduced absorption of neutral sterols and saturated and trans fatty acids may contribute to the better serum lipid profile in rats fed higher Ca. [ABSTRACT FROM AUTHOR]