Wednesday, 26 October 2016

Minerals in the News Vol. 14, No. 10 (October 2016)

Vitamin and Mineral Intake Is Inadequate for Most Americans: What Should We Advise Patients About Supplements

J Fam Pract. 2016 Sep;65(9 Suppl):S1-S8.
Blumberg JB, et al.

(AA) This supplement examines the role of vitamin and mineral supplements in increasing nutrient intake and reducing nutrient deficiencies and inadequacies. Although research is needed to study the effects of dietary supplements on chronic disease outcomes, US health care providers need to know how to advise their patients about adding vitamins and minerals to their diets.
Minerals and Trace Elements in Human Breast Milk Are Associated with Guatemalan Infant Anthropometric Outcomes within the First 6 Months

J Nutr. 2016 Oct;146(10):2067-2074. Epub 2016 Aug 24.
Li C, et al.

(AA) BACKGROUND: Breast milk is the recommended source of nutrients for infant growth, but its adequacy to meet infants' mineral and trace element needs is unknown.

OBJECTIVES: We used breast-milk mineral and trace element concentrations of Guatemalan mothers at 3 lactation stages to estimate total daily intakes and to determine whether intakes were associated with early infant growth.

METHODS: In this cross-sectional study, breast-milk samples were collected from Mam-Mayan mothers during transitional (5-17 d, n = 56), early (18-46 d, n = 75), and established (4-6 mo, n = 103) lactation; z scores for weight (WAZ), length (LAZ), and head circumference (HCAZ) were measured. Concentrations of 11 minerals (calcium, potassium, magnesium, sodium, copper, iron, manganese, rubidium, selenium, strontium, and zinc) were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). WHO equations were used to calculate the estimated energy requirement, which was divided by the energy density of breast milk to estimate daily milk volume, and this number was multiplied by breast-milk mineral concentrations to estimate intakes. Principal component analyses identified clusters of minerals; principal components (PCs) were used in regression analyses for anthropometric outcomes.

RESULTS: Estimated breast-milk intakes during established lactation were insufficient to compensate for the lower milk sodium, copper, manganese, and zinc concentrations in male infants and the lower sodium, iron and manganese concentrations in female infants. Estimated intakes of calcium, magnesium, potassium, sodium, and selenium were below the Institute of Medicine Adequate Intake for both sexes at all 3 stages of lactation. In early lactation, multiple linear regressions showed that PC1 (calcium, magnesium, potassium, rubidium, and strontium intakes) was positively associated with WAZ, LAZ, and HCAZ. In established lactation, the same PC with sodium added was positively associated with all 3 anthropometric outcomes; a second PC (PC2: zinc, copper, and selenium intakes) was associated with WAZ and LAZ but not HCAZ.

CONCLUSIONS: Breast milk may be inadequate in selected minerals and trace elements where higher estimated intakes were associated with greater infant growth.
High Prevalence of Inadequate Calcium and Iron Intakes by Mexican Population Groups as Assessed by 24-Hour Recalls

J Nutr. 2016 Sep;146(9):1874S-80S. doi: 10.3945/jn.115.227074. Epub 2016 Aug 10.
Sánchez-Pimienta TG, et al.

(AA) BACKGROUND: A National Health and Nutrition Survey (ENSANUT) conducted in Mexico in 1999 identified a high prevalence of inadequate mineral intakes in the population by using 24-h recall questionnaires. However, the 1999 survey did not adjust for within-person variance. The 2012 ENSANUT implemented a more up-to-date 24-h recall methodology to estimate usual intake distributions and prevalence of inadequate intakes.

OBJECTIVE: We examined the distribution of usual intakes and prevalences of inadequate intakes of calcium, iron, magnesium, and zinc in the Mexican population in groups defined according to sex, rural or urban area, geographic region of residence, and socioeconomic status (SES).

We used dietary intake data obtained through the 24-h recall automated multiple-pass method for 10,886 subjects as part of ENSANUT 2012. A second measurement on a nonconsecutive day was obtained for 9% of the sample. Distributions of usual intakes of the 4 minerals were obtained by using the Iowa State University method, and the prevalence of inadequacy was estimated by using the Institute of Medicine's Estimated Average Requirement cutoff.

RESULTS: Calcium inadequacy was 25.6% in children aged 1-4 y and 54.5-88.1% in subjects >5 y old. More than 45% of subjects >5 y old had an inadequate intake of iron. Less than 5% of children aged <12 y and 25-35% of subjects aged >12 y had inadequate intakes of magnesium, whereas zinc inadequacy ranged from <10% in children aged <12 y to 21.6% in men aged ≥20 y. Few differences were found between rural and urban areas, regions, and tertiles of SES.

CONCLUSIONS: Intakes of calcium, iron, magnesium, and zinc are inadequate in the Mexican population, especially among adolescents and adults. These results suggest a public health concern that must be addressed.
A review of iron studies in overweight and obese children and adolescents: a double burden in the young

Eur J Nutr. 2016 Oct;55(7):2179-97. doi: 10.1007/s00394-016-1155-7. Epub 2016 Feb 16.
Hutchinson C, et al.

(AA) INTRODUCTION: The connection between iron and excessive adiposity has received much research interest. Although children and adolescents have unique developmental phases and nutritional demands, to date, reviews of iron in the overweight (OW) and obese (OB) have combined studies of children and adults or have focussed on adults.

PURPOSE: The aim of this review was to critically evaluate studies of the relationship between iron and OW and obesity in children and adolescents, with emphasis on iron status, oral iron response, dietary intake and systemic inflammatory markers.

METHODS: A PubMed search was conducted to identify relevant articles published up to December 2015. Combinations of the following keywords were used: iron, OW, OB, children, adolescents, diet, hepcidin, inflammation, fortification, supplementation, weight loss, trace elements, obesity, iron deficiency (ID), minerals.

RESULTS AND CONCLUSION: A higher prevalence of ID, or risk of ID, among OW and OB children and adolescents has been consistently observed. Chronic inflammation caused by excessive adiposity offers a plausible explanation for this finding, rather than dietary factors. However, future studies must employ screening for the presence of both acute and chronic infections and inflammatory conditions and report other factors such as pubertal status. Intervention studies, although few, indicate that OW and OB children and adolescents have reduced response to oral iron. Further trials are needed to explore the connection between body fat mass, inflammatory proteins and iron absorption, together with the effect of weight loss on iron status in iron-deficient OW and OB children and adolescents.
Effect of Spirulina maxima Supplementation on Calcium, Magnesium, Iron, and Zinc Status in Obese Patients with Treated Hypertension

Biol Trace Elem Res. 2016 Sep;173(1):1-6. doi: 10.1007/s12011-016-0623-5. Epub 2016 Jan 16.
Suliburska J, et al.

(AA) The effects of Spirulina maxima supplementation on calcium, magnesium, iron, and zinc status were studied in a double-blind placebo-controlled trial of 50 obese subjects with treated hypertension, each randomized to receive 2 g of spirulina or a placebo daily for 3 months. At baseline and after treatment, the calcium, magnesium, iron, and zinc concentration in plasma was assessed. It was found that 3 months of S. maxima supplementation resulted in a significant decrease in the iron level in the plasma of obese patients. In conclusion, this is the first clinical study on the influence of spirulina supplementation on mineral status in obese patients with hypertension. Spirulina supplementation affects the iron status of obese Caucasians with well-treated hypertension.