Gestur I. Palsson

Iron status in 2-year-old Icelandic children and associations with dietary intake and growth

Objective: To investigate the effects of food and nutrient intake at 2 y and growth from birth on iron status at 2 y in a population with high birth weight.Design: In a cross-sectional study, childrens food consumption and body size measurements were recorded and blood samples taken. Weighed 3-day food records were used to analyse food and nutrient intake.Setting: Children were recruited from across Iceland from the Icelandic National Registry by the University of Iceland, Computing Services. The children in the sample were born over a 1-y period.Subjects: Parents of randomly selected 2-year-old children (n=130) were contacted, and 72% (n=94) participated. Blood samples were analysed in 76% (n=71) of participating children.Results: In total, 9% of the children were iron-deficient (serum ferritin (SF)<12 μg/l and mean corpuscular volume (MCV) <74 fl) and 1.4% were also anaemic (Hb<105 g/l), while 27% of children were iron-depleted (SF<12 μg/l). Iron status indices were negatively associated with cows milk consumption. Half of children consuming>500 g cows milk/day (n=10) were iron-deficient, while one child in 58 consuming<500 g cows milk/day had iron deficiency (P<0.001). In multiple regression analyses, also biscuits and crackers consumption was positively associated with MCV. Weight gain from birth to 2 y was negatively associated with SF (adjusted R2=0.15; P=0.002; n=58). Iron-depleted children were heavier than children not iron-depleted (14.7±1.3 vs 13.8±1.7 kg; P=0.043), had higher BMI (17.7±1.5 vs 16.7±1.4 kg/m2; P=0.028) and gained more weight from birth (11.2±1.3 vs. 10.0±1.6 kg; P=0.011).Conclusions: The results suggest that cows milk consumption above 500 g/day should be avoided at the age of 2 y for better iron status. Iron depletion at 2 y is associated with faster growth from birth.Sponsorship: Research Fund of the University of Iceland.

Timing of the Introduction of Complementary Foods in Infancy: A Randomized Controlled Trial

OBJECTIVE: To increase knowledge on iron status and growth during the first 6 months of life. We hypothesized that iron status would be better in infants who received complementary foods in addition to breast milk compared with those exclusively breastfed. METHODS: One hundred nineteen healthy term (≥37 weeks) singleton infants were randomly assigned to receive either complementary foods in addition to breast milk from age 4 months (CF) or to exclusive breastfeeding for 6 months (EBF). Dietary data were collected by 3-day weighed food records, and data on iron status and growth were also collected. RESULTS: One hundred infants (84%) completed the trial. Infants in the CF group had higher mean serum ferritin levels at 6 months (P = .02), which remained significant when adjusted for baseline characteristics. No difference was seen between groups in iron deficiency anemia, iron deficiency, or iron depletion. The average daily energy intake from complementary foods of 5-month-olds in the CF group was 36.8 kJ per kg body weight. Infants in both groups grew at the same rate between 4 and 6 months of age. CONCLUSIONS: In a high-income country, adding a small amount of complementary food in addition to breast milk to infants’ diets from 4 months of age does not affect growth rate between 4 and 6 months, but has a small and positive effect on iron status at 6 months. The biological importance of this finding remains to be determined.

Nutrition and Iron Status of 1-Year Olds following a Revision in Infant Dietary Recommendations.

A previous study showed low iron status in 12-month-old Icelandic infants associated most strongly with cows milk intake and growth. Infant dietary recommendations were revised in 2003. This study investigated nutrition and iron status in a new infant cohort. Subjects/Methods. Randomly selected infants were prospectively investigated for diet, anthropometry, and iron status (n = 110–141). Results. Breastfeeding initiation rate was 98%; 38% of 5-month olds were exclusively and 20% of 12-month olds partially breastfed. Formula was given to 21% of 6-month olds and 64% of 12-month olds, but cows milk to 2.5% and 54.4% of 6- and 12-month olds, respectively. Iron depletion (serum ferritin < 12 μg/L) affected 5.8%, 1.4% were also iron deficient (MCV < 74 fl), and none were anemic (Hb < 105 g/l). Iron status associated negatively with growth and breastfeeding duration and positively with meat and formula intake at 9–12 months, but not with cows milk. Conclusion. Improved iron status might be explained by a shift from cows milk to formula in the diet of Icelandic 6–12-month olds. Dietary changes altered associations between foods and iron status.

Iron status at 1 and 6 years versus developmental scores at 6 years in a well-nourished affluent population

Aim: To examine the association between iron status at 1 and 6 years with development at 6 years.

Iron status in 6-y-old children: associations with growth and earlier iron status

Objective:To investigate the iron status of 6-y-old children and its association with growth and earlier iron status.Design:In a cross-sectional study, childrens body size measurements were recorded and blood samples taken near their sixth birthday.Subjects:A sample of 188 children, randomly selected in two previous studies, was contacted, and 139(74%) agreed to participate.Results:No children had iron deficiency anaemia, one was iron-deficient (serum ferritin (SF) <15 μg/l and mean corpuscular volume (MCV) <76 fl but 16% had depleted iron stores (SF<15 μg/l). Iron status indices were generally higher than at 1 and 2 y, but correlation was seen between iron status indices at 6 y and earlier values. Haemoglobin concentration at 6 y was negatively associated with length gain from birth to 1 y (B±s.e.=−1.269±0.452; P=0.007; adj. R2=0.119) (n=52), and proportional weight gain from birth to 1 y was higher among children with SF<15 μg/l at 6 y (295±33%; n=10) than those with SF≥15 μg/l (258±31%; n=49) (P=0.001). MCV at 2 y predicted weight gain from 2 to 6 y (B±s.e.=1.721±0.581; P=0.005; adj. R2=0.153) (n=44); also, children with SF<15 μg/l at 6 y (n=9) gained 7.8±1.2 kg from 2 to 6 y, while children with SF≥15 μg/l (n=35) gained 9.6±2.8 kg (P=0.007), furthermore a difference was seen in proportional weight gain from 2 to 6 y between children with depleted iron stores at 2 y and not, or 156±13 vs 169±18% (P=0.038).Conclusion:The results suggest that low iron status at 1 and 2 y might lead to slower growth up to 6 y of age. Low iron status at 1 and 2 y and/or slower growth from 1 and 2 y up to 6 y might contribute to worse iron status at 6 y, while faster growth in early childhood is related to lower iron status.Sponsorship:The Icelandic Research Council.

Associations of iron status with dietary and other factors in 6-year-old children

Objective:To investigate the associations of iron status at 6 years of age with dietary and other factors.Design:In a cross-sectional study, childrens dietary intakes (3-day weighed food record) were recorded, body size was measured and blood samples were taken near their sixth birthday.Subjects:A sample of 188 children, from two previous studies (cohorts 1 and 2), was contacted, and 139 (74%) agreed to participate.Results:Multiple regression analyses with dietary and other factors showed that meat and fish consumption, multivitamin/mineral supplement intake (both positively) and cows milk product consumption (negatively) were associated with log serum ferritin (SF) (adjusted R 2=0.125; P=0.028; n=129), and juices and residence (rural>urban) with haemoglobin (Hb) (adjusted R 2=0.085; P=0.034; n=127). Of 21 multivitamin/mineral consumers, none had depleted iron stores compared to 21 iron-depleted of 108 non-consumers (P=0.024). Children living in rural areas (<10 000 inhabitants) (n=33) had higher mean corpuscular volume (MCV) (83.3±2.3 fl) than those living in urban areas (>10 000 inhabitants) (82.1±3.2 fl; n=103) (P=0.048). Multiple regression analyses with dietary and other factors and growth showed in cohort 1 that residence (rural>urban), weight gain 0–1years (negatively), and meat and fish intake (positively) were associated with Hb (adjusted R 2=0.323; P=0.030; n=51), meat and fish (positively) with both log SF (adjusted R 2=0.069; P=0.035; n=52) and MCV (adjusted R 2=0.064; P=0.035; n=52), and in cohort 2 cows milk product consumption (negatively) was associated with log SF (adjusted R 2=0.119; P=0.017; n=41) and residence (rural>urban) with MCV (adjusted R 2=0.102; P=0.025; n=41).Conclusions:Consumption of meat and fish and possibly also juices, as well as multivitamin/mineral intake might affect iron status in 6-year-old children positively, whereas cows milk product consumption might affect iron status negatively. Slower growth in the first year of life and rural residence are positively related to iron status of 6-year-olds.Sponsorship:The Icelandic Research Council.

Association of birth weight and breast-feeding with coronary heart disease risk factors at the age of 6 years.

BACKGROUND AND AIM It has been shown that early growth and nutrition affect health in childhood and later life. The aim of this study was to assess the association of birth weight and breast-feeding in infancy with body mass index (BMI) and serum lipids at the age of six years. The contributions of current macronutrient intake, maternal age and BMI were assessed. METHODS AND RESULTS This was a longitudinal observational study of 120 randomly chosen children whose birth weight and duration of breast-feeding had been recorded. At the age of six years, their weight and height, and serum cholesterol (total, LDL and HDL) and triglyceride levels were measured at healthcare centres in Iceland. Dietary intake at six years was estimated using 3-day weighed food records. The duration of breast-feeding negatively correlated with BMI in 6-year-old boys (B = -0.19 +/- 0.07, p = 0.011) but not in girls; after adjusting for maternal BMI, the relationship in boys was of borderline significance (p = 0.087). The 6-year-old boys who had been breast-fed for < 6 months had a significantly higher BMI (18.0 +/- 2.5 kg/m2) than those breast-fed for 8-9 months (15.8 +/- 1.2 kg/m2, p = 0.006) or > or = 10 months (15.7 +/- 1.2 kg/m2, p = 0.005). A longer duration of breast-feeding was related to higher HDL-cholesterol levels in 6-year-old girls (B = 0.03 +/- 0.01, p = 0.032), but not boys. Birth weight was not related to BMI or serum lipid levels at the age of 6 years. CONCLUSION In this high birth weight population, a longer duration of breast-feeding may be effective in preventing childhood overweight, at least among boys. Breast-feeding also seems to be related to an improved lipid profile in girls.

Animal protein intake at 12 months is associated with growth factors at the age of six.

To study the associations between protein intake from different sources with anthropometry and serum insulin‐like growth factor 1 (IGF‐1) in infancy and childhood.

Vitamin D intake and status in 12-month-old infants at 63-66° N.

The objective was to assess the vitamin D status in healthy 12-month-old infants in relation to quantity and sources of dietary vitamin D, breastfeeding and seasons. Subjects were 76 12-month-old infants. Serum levels of 25-hydroxyvitamin D (25(OH)D) ≥ 50 nmol/L were considered indicative of vitamin D sufficiency and 25(OH)D < 27.5 nmol/L as being indicative of increased risk for rickets. Additionally, 25(OH)D > 125 nmol/L was considered possibly adversely high. Total vitamin D at 9–12 months (eight data collection days) included intake from diet and supplements. The mean ± SD of vitamin D intake was 8.8 ± 5.2 μg/day and serum 25(OH)D 98.1 ± 32.2 nmol/L (range 39.3–165.5). Ninety-two percent of infants were vitamin D sufficient and none at increased risk for rickets. The 26% infants using fortified products and supplements never/irregularly or in small amounts had lower 25(OH)D (76.8 ± 27.1 nmol/L) than the 22% using fortified products (100.0 ± 31.4 nmol/L), 18% using supplements (104.6 ± 37.0 nmol/L) and 33% using both (110.3 ± 26.6 nmol/L). Five of six infants with 25(OH)D < 50 nmol/L had no intake of supplements or fortified products from 0 to 12 months. Supplement use increased the odds of 25(OH)D > 125 nmol/L. Breastfeeding and season did not affect vitamin D status. The majority of infants were vitamin D sufficient. Our findings highlight the need for vitamin D supplements or fortified products all year round, regardless of breastfeeding.

Iron status and developmental scores in 6-year-olds highlights ongoing need to tackle iron deficiency in infants

To investigate iron status and developmental scores at 6 years of age in a population with decreased prevalence of iron deficiency in infancy. Iron status at 6 years and tracking from 12 months were also studied.