Identification of differences in health impact modelling of salt reduction.

We examined whether specific input data and assumptions explain outcome differences in otherwise comparable health impact assessment models. Seven population health models estimating the impact of salt reduction on morbidity and mortality in western populations were compared on four sets of key features, their underlying assumptions and input data. Next, assumptions and input data were varied one by one in a default approach (the DYNAMO-HIA model) to examine how it influences the estimated health impact. Major differences in outcome were related to the size and shape of the dose-response relation between salt and blood pressure and blood pressure and disease. Modifying the effect sizes in the salt to health association resulted in the largest change in health impact estimates (33% lower), whereas other changes had less influence. Differences in health impact assessment model structure and input data may affect the health impact estimate. Therefore, clearly defined assumptions and transparent reporting for different models is crucial. However, the estimated impact of salt reduction was substantial in all of the models used, emphasizing the need for public health actions.

How may a shift towards a more sustainable food consumption pattern affect nutrient intakes of Dutch children?

OBJECTIVE: Food has a considerable environmental impact. Diets with less meat and dairy reduce environmental impact but may pose nutritional challenges for children. The current modelling study investigates the impact of diets with less or no meat and dairy products on nutrient intakes. DESIGN: Energy and nutrient intakes were assessed for observed consumption patterns (reference) and two replacement scenarios with data from the Dutch National Food Consumption Survey - Young Children (2005-2006). In the replacement scenarios, 30 % or 100 % of the consumed dairy and meat (in grams) was replaced by plant-derived foods with similar use. SETTING: The Netherlands. SUBJECTS: Children (n 1279) aged 2-6 years. RESULTS: Partial and full replacement of meat and dairy foods by plant-derived foods reduced SFA intake by 9 % and 26 %, respectively, while fibre intake was 8 % and 29 % higher. With partial replacement, micronutrient intakes were similar, except for lower vitamin B12 intake. After full meat and dairy replacement, mean intakes of Ca, Zn and thiamin decreased by 5-13 %, and vitamin B12 intake by 49 %, while total intake of Fe was higher but of lower bioavailability. With full replacement, the proportion of girls aged 4-6 years with intakes below recommendations was 15 % for thiamin, 10 % for vitamin B12 and 6 % for Zn. CONCLUSIONS: Partial replacement of meat and dairy by plant-derived foods is beneficial for children's health by lowering SFA intake, increasing fibre content and maintaining similar micronutrient intakes. When full replacements are made, attention is recommended to ensure adequate thiamin, vitamin B12 and Zn intakes.

WHO European Childhood Obesity Surveillance Initiative: health-risk behaviours on nutrition and physical activity in 6-9-year-old schoolchildren.

OBJECTIVE: To assess to what extent eight behavioural health risks related to breakfast and food consumption and five behavioural health risks related to physical activity, screen time and sleep duration are present among schoolchildren, and to examine whether health-risk behaviours are associated with obesity. DESIGN: Cross-sectional design as part of the WHO European Childhood Obesity Surveillance Initiative (school year 2007/2008). Children's behavioural data were reported by their parents and children's weight and height measured by trained fieldworkers. Descriptive statistics and logistic regression analyses were performed. SETTING: Primary schools in Bulgaria, Lithuania, Portugal and Sweden; paediatric clinics in the Czech Republic. SUBJECTS: Nationally representative samples of 6-9-year-olds (n 15 643). RESULTS: All thirteen risk behaviours differed statistically significantly across countries. Highest prevalence estimates of risk behaviours were observed in Bulgaria and lowest in Sweden. Not having breakfast daily and spending screen time ≥2 h/d were clearly positively associated with obesity. The same was true for eating 'foods like pizza, French fries, hamburgers, sausages or meat pies' >3 d/week and playing outside <1 h/d. Surprisingly, other individual unhealthy eating or less favourable physical activity behaviours showed either no or significant negative associations with obesity. A combination of multiple less favourable physical activity behaviours showed positive associations with obesity, whereas multiple unhealthy eating behaviours combined did not lead to higher odds of obesity. CONCLUSIONS: Despite a categorization based on international health recommendations, individual associations of the thirteen health-risk behaviours with obesity were not consistent, whereas presence of multiple physical activity-related risk behaviours was clearly associated with higher odds of obesity.

Health gain by salt reduction in europe: a modelling study.

Excessive salt intake is associated with hypertension and cardiovascular diseases. Salt intake exceeds the World Health Organization population nutrition goal of 5 grams per day in the European region. We assessed the health impact of salt reduction in nine European countries (Finland, France, Ireland, Italy, Netherlands, Poland, Spain, Sweden and United Kingdom). Through literature research we obtained current salt intake and systolic blood pressure levels of the nine countries. The population health modeling tool DYNAMO-HIA including country-specific disease data was used to predict the changes in prevalence of ischemic heart disease and stroke for each country estimating the effect of salt reduction through its effect on blood pressure levels. A 30% salt reduction would reduce the prevalence of stroke by 6.4% in Finland to 13.5% in Poland. Ischemic heart disease would be decreased by 4.1% in Finland to 8.9% in Poland. When salt intake is reduced to the WHO population nutrient goal, it would reduce the prevalence of stroke from 10.1% in Finland to 23.1% in Poland. Ischemic heart disease would decrease by 6.6% in Finland to 15.5% in Poland. The number of postponed deaths would be 102,100 (0.9%) in France, and 191,300 (2.3%) in Poland. A reduction of salt intake to 5 grams per day is expected to substantially reduce the burden of cardiovascular disease and mortality in several European countries.

WHO European Childhood Obesity Surveillance Initiative: School nutrition environment and body mass index in primary schools.

BACKGROUND: Schools are important settings for the promotion of a healthy diet and sufficient physical activity and thus overweight prevention. OBJECTIVE: To assess differences in school nutrition environment and body mass index (BMI) in primary schools between and within 12 European countries. METHODS: Data from the World Health Organization (WHO) European Childhood Obesity Surveillance Initiative (COSI) were used (1831 and 2045 schools in 2007/2008 and 2009/2010, respectively). School personnel provided information on 18 school environmental characteristics on nutrition and physical activity. A school nutrition environment score was calculated using five nutrition-related characteristics whereby higher scores correspond to higher support for a healthy school nutrition environment. Trained field workers measured children's weight and height; BMI-for-age (BMI/A) Z-scores were computed using the 2007 WHO growth reference and, for each school, the mean of the children's BMI/A Z-scores was calculated. RESULTS: Large between-country differences were found in the availability of food items on the premises (e.g., fresh fruit could be obtained in 12%-95% of schools) and school nutrition environment scores (range: 0.30-0.93). Low-score countries (Bulgaria, Czech Republic, Greece, Hungary, Latvia and Lithuania) graded less than three characteristics as supportive. High-score (≥0.70) countries were Ireland, Malta, Norway, Portugal, Slovenia and Sweden. The combined absence of cold drinks containing sugar, sweet snacks and salted snacks were more observed in high-score countries than in low-score countries. Largest within-country school nutrition environment scores were found in Bulgaria, Czech Republic, Greece, Hungary, Latvia and Lithuania. All country-level BMI/A Z-scores were positive (range: 0.20-1.02), indicating higher BMI values than the 2007 WHO growth reference. With the exception of Norway and Sweden, a country-specific association between the school nutrition environment score and the school BMI/A Z-score was not observed. CONCLUSIONS: Some European countries have implemented more school policies that are supportive to a healthy nutrition environment than others. However, most countries with low school nutrition environment scores also host schools with supportive school environment policies, suggesting that a uniform school policy to tackle the "unhealthy" school nutrition environment has not been implemented at the same level throughout a country and may underline the need for harmonized school policies.

WHO European Childhood Obesity Surveillance Initiative: body mass index and level of overweight among 6-9-year-old children from school year 2007/2008 to school year 2009/2010.

BACKGROUND: The World Health Organization (WHO) Regional Office for Europe has established the Childhood Obesity Surveillance Initiative (COSI) to monitor changes in overweight in primary-school children. The aims of this paper are to present the anthropometric results of COSI Round 2 (2009/2010) and to explore changes in body mass index (BMI) and overweight among children within and across nine countries from school years 2007/2008 to 2009/2010. METHODS: Using cross-sectional nationally representative samples of 6-9-year-olds, BMI, anthropometric Z-scores and overweight prevalence were derived from measured weight and height. Significant changes between rounds were assessed using variance and t-tests analyses. RESULTS: At Round 2, the prevalence of overweight (including obesity; WHO definitions) ranged from 18% to 57% among boys and from 18% to 50% among girls; 6 - 31% of boys and 5 - 21% of girls were obese. Southern European countries had the highest overweight prevalence. Between rounds, the absolute change in mean BMI (range: from -0.4 to +0.3) and BMI-for-age Z-scores (range: from -0.21 to +0.14) varied statistically significantly across countries. The highest significant decrease in BMI-for-age Z-scores was found in countries with higher absolute BMI values and the highest significant increase in countries with lower BMI values. The highest significant decrease in overweight prevalence was observed in Italy, Portugal and Slovenia and the highest significant increase in Latvia and Norway. CONCLUSIONS: Changes in BMI and prevalence of overweight over a two-year period varied significantly among European countries. It may be that countries with higher prevalence of overweight in COSI Round 1 have implemented interventions to try to remedy this situation.

Potential effect of salt reduction in processed foods on health.

BACKGROUND: Excessive salt intake has been associated with hypertension and increased cardiovascular disease morbidity and mortality. Reducing salt intake is considered an important public health strategy in the Netherlands. OBJECTIVE: The objective was to evaluate the health benefits of salt-reduction strategies related to processed foods for the Dutch population. DESIGN: Three salt-reduction scenarios were developed: 1) substitution of high-salt foods with low-salt foods, 2) a reduction in the sodium content of processed foods, and 3) adherence to the recommended maximum salt intake of 6 g/d. Health outcomes were obtained in 2 steps: after salt intake was modeled into blood pressure levels, the Chronic Disease Model was used to translate modeled blood pressures into incidences of cardiovascular diseases, disability-adjusted life years (DALYs), and life expectancies. Health outcomes of the scenarios were compared with health outcomes obtained with current salt intake. RESULTS: In total, 4.8% of acute myocardial infarction cases, 1.7% of congestive heart failure cases, and 5.8% of stroke cases might be prevented if salt intake meets the recommended maximum intake. The burden of disease might be reduced by 56,400 DALYs, and life expectancy might increase by 0.15 y for a 40-y-old individual. Substitution of foods with comparable low-salt alternatives would lead to slightly higher salt intake reductions and thus to more health gain. The estimates for sodium reduction in processed foods would be slightly lower. CONCLUSION: Substantial health benefits might be achieved when added salt is removed from processed foods and when consumers choose more low-salt food alternatives.

Monitoring salt and iodine intakes in Dutch adults between 2006 and 2010 using 24 h urinary sodium and iodine excretions.

OBJECTIVE: To monitor the effectiveness of salt-reduction initiatives in processed foods and changes in Dutch iodine policy on Na and iodine intakes in Dutch adults between 2006 and 2010. DESIGN: Two cross-sectional studies among adults, conducted in 2006 and 2010, using identical protocols. Participants collected single 24 h urine samples and completed two short questionnaires on food consumption and urine collection procedures. Daily intakes of salt, iodine, K and Na:K were estimated, based on the analysis of Na, K and iodine excreted in urine. SETTING: Doetinchem, the Netherlands. SUBJECTS: Men and women aged 19 to 70 years were recruited through random sampling of the Doetinchem population and among participants of the Doetinchem Cohort Study (2006: n 317, mean age 48·9 years, 43 % men; 2010: n 342, mean age 46·2 years, 45 % men). RESULTS: While median iodine intake was lower in 2010 (179 µg/d) compared with 2006 (257 µg/d; P < 0·0001), no difference in median salt intake was observed (8·7 g/d in 2006 v. 8·5 g/d in 2010, P = 0·70). In 2006, median K intake was 2·6 g/d v. 2·8 g/d in 2010 (P < 0·01). In this 4-year period, median Na:K improved from 2·4 in 2006 to 2·2 in 2010 (P < 0·001). CONCLUSIONS: Despite initiatives to lower salt in processed foods, dietary salt intake in this population remains well above the recommended intake of 6 g/d. Iodine intake is still adequate, although a decline was observed between 2006 and 2010. This reduction is probably due to changes in iodine policy.

Impact of multi-micronutrient supplementation on growth and morbidity of HIV-infected South African children.

Poor growth, micronutrient deficiencies and episodes of diarrhea and respiratory infections occur frequently in HIV-infected children. We investigated whether multi-micronutrient supplementation would improve the growth performance and reduce the number of episodes of diarrhea and/or of respiratory symptoms in HIV-infected children. In a double-blind randomized trial, HIV-infected South African children aged 4-24 months (n = 201) were assigned to receive multi-micronutrient supplements or placebo daily for six months. The children were assessed for respiratory symptoms or diarrhea bi-weekly; weights and heights were measured monthly. In total, 121 children completed the six month follow up study period (60%). A total of 43 children died; 27 of them had received supplements. This difference in mortality was not statistically significant (p = 0.12). Weight-for-height Z-scores improved significantly (p < 0.05) among children given supplements compared with those given placebo (0.40 (0.09-0.71)) versus -0.04 (-0.39-0.31) (mean (95% CI)). Height-for-age Z-scores did not improve in both treatment groups. The number of monthly episodes of diarrhea in the placebo group (0.36 (0.26-0.46)) was higher (p = 0.09) than in the supplement group (0.25 (0.17-0.33)) and the number of monthly episodes of respiratory symptoms was significantly higher (p < 0.05) among children on placebos (1.01 (0.83-1.79)) than those on supplements (0.66 (0.52-0.80)). Multi-micronutrient supplements significantly improved wasting and reduced the number of episodes of diarrhea and respiratory symptoms.

Effect of antenatal zinc supplementation on impetigo in infants in Bangladesh.

We sought to determine the effects of maternal zinc supplementation on skin infections among infants in poor urban areas of Dhaka, Bangladesh. A double-blind, placebo-controlled, randomized trial was conducted among 199 and 221 Bangladeshi infants whose mothers were administered 30 mg daily of zinc or placebo, respectively. The mothers received zinc supplementation from 12-16 weeks' gestation until delivery, and the infants were followed up until 6 months of age. Among the infants of mothers who received zinc supplementation during the antenatal period, 10.6% had at least 1 episode of impetigo compared with 19.6% of the infants of mothers in the placebo group (P = 0.01). Infants in the treatment group had a 54% reduction in incidence rate of episodes of impetigo when compared with infants in the placebo group (P = 0.01). The effect of zinc supplementation was more pronounced among male infants (64% reduction) and intrauterine growth restricted and low birth weight infants (73% reduction) and among infants of mothers with increased parity (60% reduction) or decreased socioeconomic status (71% reduction).

Duration of hospitalization and appetite of HIV-infected South African children.

Human immunodeficiency virus (HIV)-infected children generally show poor growth. Episodes of diarrhoea and pneumonia in HIV-infected children are thought to be more severe than in HIV-uninfected children. The objective of this study was to compare duration of hospitalization, appetite and nutritional status of HIV-infected children with that of uninfected children. A cross-sectional study was performed on children (2-24 months) admitted with diarrhoea or pneumonia to the university hospital. Children were tested for HIV, and the duration of hospitalization was noted for 189 children. Follow-up for blood analysis (n=154) and appetite measurement (n=48) was performed 4-8 weeks after discharge. Appetite was measured as ad libitum intake of a commercial infant cereal using highly standardized procedures. Hospitalization (in days) was significantly longer in HIV-infected children; among children admitted with diarrhoea (5.9 ± 1.9 vs. 3.8 ± 1.5) (mean ± standard deviation) and with pneumonia (9.0 ± 2.5 vs. 5.9 ± 1.9). Serum zinc, iron and transferrin concentrations, and haemoglobin levels were significantly lower in HIV-infected children compared with uninfected children. Appetites [amounts eaten (g) per kg body weight] of HIV-infected children were significantly poorer than those of HIV-uninfected children (18.6 ± 5.8 vs. 25.2 ± 7.4). The eating rates (g min(-1) ) of HIV-infected children were also slower (17.6 ± 6.2 vs. 10.1 ± 3.7) Mean Z-scores for length-for-age were significantly lower among HIV-infected children compared with HIV-uninfected children. Weight-for-length Z-scores were not significantly different. In summary, HIV-infected children had a 55% longer duration of hospitalization and a 21% lower appetite.

Effect of dietary fat supplementation during late pregnancy and first six months of lactation on maternal and infant vitamin A status in rural Bangladesh.

Dietary fat intake is extremely low in most communities with vitamin A deficiency. However, its role in vitamin A status of pregnant and lactating women is poorly understood. The aim of the study was to examine the effect of supplementing women with fat from mid-/late pregnancy until six months postpartum on their vitamin A status and that of their infants. Women recruited at 5-7 months of gestation were supplemented daily with 20 mL of soybean-oil (n = 248) until six months postpartum or received no supplement (n = 251). Dietary fat intake was assessed by 24-hour dietary recall at enrollment and at 1, 3 and 6 months postpartum. Concentrations of maternal plasma retinol, beta-carotene, and lutein were measured at enrollment and at 1, 3 and 6 months postpartum, and those of infants at six months postpartum. Concentration of breastmilk retinol was measured at 1, 3 and 6 months postpartum. The change in concentration of plasma retinol at three months postpartum compared to pregnancy was significantly higher in the supplemented compared to the control women (+0.04 vs -0.07 micromol/L respectively; p < 0.05). Concentrations of plasma beta-carotene and lutein declined in both the groups during the postpartum period but the decline was significantly less in the supplemented than in the control women at one month (beta-carotene -0.07 vs -0.13 micromol/L, p < 0.05); lutein -0.26 vs -0.49 micromol/L, p < 0.05) and three months (beta-carotene -0.04 vs -0.08 micromol/L, p < 0.05; lutein -0.31 vs -0.47 micromol/L, p < 0.05). Concentration of breastmilk retinol was also significantly greater in the supplemented group at three months postpartum than in the controls (0.68 +/- 0.35 vs 0.55 +/- 0.34 micromol/L respectively, p < 0.03). Concentrations of infants' plasma retinol, beta-carotene, and lutein, measured at six months of age, did not differ between the groups. Fat supplementation during pregnancy and lactation in women with a very low intake of dietary fat has beneficial effects on maternal postpartum vitamin A status.

Short-term micronutrient supplementation reduces the duration of pneumonia and diarrheal episodes in HIV-infected children.

The duration of pneumonia and of diarrhea is reported to be longer in HIV-infected than in uninfected children. We assessed the effect of a multi-micronutrient supplement on the duration of hospitalization in HIV-infected children. In a double-blind, randomized trial, HIV-infected children (4-24 mo) who were hospitalized with diarrhea or pneumonia were enrolled (n = 118) and given a daily dose of a multi-micronutrient supplement (containing vitamins A, B complex, C, D, E, and folic acid, as well as copper, iron, and zinc at levels based on recommended daily allowances) or a placebo until discharge from the hospital. Children's weights and heights were measured after enrollment and micronutrient concentrations were measured before discharge. On recovery from diarrhea or pneumonia, the children were discharged and the duration of hospitalization was noted. Anthropometric indices and micronutrient concentrations did not differ between children who received supplements and those who received placebos. Overall, the duration of hospitalization was shorter (P < 0.05) among children who were receiving supplements (7.3 +/- 3.9 d) (mean +/- SD) than in children who were receiving placebos (9.0 +/- 4.9); this was independent of admission diagnosis. In children admitted with diarrhea, the duration of hospitalization was 1.6 d (19%) shorter among children receiving supplements than in those receiving placebos, and hospitalization for pneumonia was 1.9 d (20%) shorter among children receiving supplements. Short-term multi-micronutrient supplementation significantly reduced the duration of pneumonia or diarrhea in HIV-infected children who were not yet receiving antiretroviral therapy and who remained alive during hospitalization.

Improved appetite after multi-micronutrient supplementation for six months in HIV-infected South African children.

The aim of the study was to assess the effect of multi-micronutrient supplementation on the appetite of HIV-infected children. HIV-infected children (6-24 months) who had previously been hospitalized were enrolled into a double-blind randomized trial, and given daily multi-micronutrient supplements or placebos for six months. Appetite tests were performed at enrollment and after three and six months. Appetite was measured as ad libitum intake of a commercial cereal test food served after an overnight fast according to standardized procedures. Body weights and total amount of test food eaten were measured. In total, 99 children completed the study (50 on supplements and 49 on placebos). Amounts eaten per kilogram body weight in the supplement group at enrollment and after six months were 36.7+/-17.7 g/kg (mean+/-SD) and 41.3+/-15.0 g/kg respectively, while the amounts in the placebo group were 47.1+/-14.9 g/kg and 45.7+/-13.1g/kg respectively. The change in amount eaten per kilogram body weight over six months was significantly higher in the supplement group (4.7+/-14.7 g/kg) than in the placebo group (-1.4+/-15.1g/kg). Multi-micronutrient supplementation for six months seems to significantly improve the appetite of HIV-infected children.

Immunization with the heptavalent pneumococcal conjugate vaccine in Bangladeshi infants and effects of zinc supplementation.

BACKGROUND: Zinc deficiency is known to impair immunologic functions. However, the effect of zinc supplementation on immune response to polysaccharide vaccines is not known. OBJECTIVE: To determine the immunogenicity of the heptavalent Pneumococcal protein conjugate (PNC) vaccine in poor Bangladeshi infants and to assess the effect of zinc supplementation on immune response to the PNC vaccine. DESIGN: We immunized a sub-cohort of 241 infants who had previously received three doses of a Hib conjugate vaccine with three doses of the heptavalent PNC vaccine at 4 weeks intervals beginning at 18+/-1 weeks of age. The infants were supplemented with daily 5 mg zinc or placebo from 4 to 33 weeks of age. Response to each of the seven PNC serotypes were assessed at 4, 24 and 33 weeks of age. RESULTS: After three doses of PNC, at 29 weeks of age, geometric mean titres for the pneumococcal serotypes ranged from 3.68 to 13.34 microg/ml. Titres were significantly higher for infants who had received PNC compared to infants who had only received DTP-Hib. Zinc supplementation resulted in higher titres for serotype 9V (4.09 microg/ml; [95% CI: 3.27; 5.10] and 3.33 microg/ml; [95% CI: 2.79; 3.96] for zinc and placebo group, respectively; p<0.05) after three doses but had no effect on other serotypes. CONCLUSIONS: A heptavalent PNC vaccine proved to be safe and immunogenic in Bangladeshi infants. Zinc supplementation enhanced the immune response to only one of the serotypes (9V). However, there was no effect on other serotypes.

The effect of zinc supplementation during pregnancy on immune response to Hib and BCG vaccines in Bangladesh.

An essential role for zinc in development of the fetal immune system has been documented. However, the effect of antenatal zinc supplementation on infants' postnatal immune response to vaccinations is unknown. The objective of this study was to evaluate the effect of zinc supplementation during pregnancy on immune response to the Bacillus Calmette-Guerin (BCG) vaccine and the Haemophilus influenzae type b (Hib) component of the combined diphtheria, tetanus toxoid and pertussis (DTP)-Haemophilus influenzae type-b (Hib)- conjugate vaccine in poor Bangladeshi infants. We immunized 405 infants whose mothers were supplemented daily with 30 mg elemental zinc or placebo beginning at 12-16 weeks gestation with the standard BCG vaccine at birth. A subcohort of 203 infants were in addition immunized at 1-month intervals with three doses of DTP-Hib vaccine starting at 9 weeks of age. The delayed hypersensitivity (PPD) skin test was performed in 345 infants at 24 weeks of age. Hib polysaccharide (PRP) antibodies were assessed for 91 infants at 4 and 24 weeks of age. In infants born with low birth weight (LBW) a lower proportion of negative responses to PPD skin test were observed in the zinc (66.2%) compared to placebo (78.5%) group (p = 0.07). No differences were observed in normal birth weight infants. There were no differences in proportion of infants above the protective thresholds for anti-PRP antibodies between zinc (81%) and placebo (89%) group. Geometric mean PRP antibody titres at 4 and 24 weeks of age were not different between groups. Zinc supplementation during pregnancy did not enhance immune response to Hib-conjugate vaccine but there was a suggestion of improved delayed hypersensitivity immune responses to BCG-vaccine in Bangladeshi LBW infants.

Effect of zinc supplementation between 1 and 6 mo of life on growth and morbidity of Bangladeshi infants in urban slums.

BACKGROUND: Evidence for an effect of zinc supplementation on growth and morbidity in very young infants in developing countries is scarce and inconsistent. OBJECTIVE: We assessed the effect of zinc supplementation on growth and morbidity in poor Bangladeshi infants aged 4-24 wk. DESIGN: Infants from Dhaka slums were enrolled at 4 wk of age and randomly assigned to receive 5 mg elemental Zn/d (n = 152) or placebo (n = 149) until 24 wk of age. They were followed weekly for information on compliance and morbidity; anthropometric measurements were performed monthly. Serum zinc was assessed at baseline and at 24 wk of age. RESULTS: At 24 wk of age, serum zinc concentrations were higher in the zinc than in the placebo group (13.3 +/- 3.8 and 10.7 +/- 2.9 micro mol/L, respectively; P < 0.001). Significantly greater weight gains were observed in the zinc than in the placebo group for 43 infants who were zinc deficient (< 9.18 micro mol/L) at baseline (3.15 +/- 0.77 and 2.66 +/- 0.80 kg, respectively; P < 0.04). In the other infants, no significant differences were observed in mean weight and length gains during the study period. Zinc-deficient infants showed a reduced risk of incidence of acute lower respiratory infection after zinc supplementation (relative risk: 0.30; 95% CI: 0.10, 0.92); among the non-zinc-deficient infants there were no significant differences between treatment groups. CONCLUSIONS: Zinc-deficient Bangladeshi infants showed improvements in growth rate and a reduced incidence of acute lower respiratory infection after zinc supplementation. In infants with serum zinc concentrations > 9.18 micro mol/L, supplementation improved only biochemical zinc status.

Nitrogen balance of healthy Dutch women before and during pregnancy.

BACKGROUND: Experimental studies including longitudinal nitrogen balance studies could provide insight into protein metabolism in pregnancy. OBJECTIVE: Our aim was to determine the development of nitrogen balance during pregnancy compared with nitrogen balance before pregnancy in women consuming imposed constant diets. We also tracked changes in muscle mass and lean body mass by measuring urinary 3-methylhistidine (3-MeH) and urinary creatinine. DESIGN: Nitrogen balance was determined over 8 d in 12 healthy Dutch women before pregnancy and at weeks 12, 23, and 34 of gestation. Complete daily diets were supplied during each balance period so that each subject's energy, protein, and macronutrient intakes were similar in amount and composition in all 4 balance periods. RESULTS: Throughout pregnancy there was no significant change in loss of nitrogen in feces and therefore no change in protein digestibility. The amount of nitrogen excreted in urine in late pregnancy (11.0 +/- 1.4 g/d) was significantly (P < 0.01) less than in early pregnancy (12.6 +/- 1.3 g/d). Nitrogen retention increased toward term, even though energy balance became progressively negative. The difference between the first (-0.4 +/- 1.7 g N/d) and third (1.2 +/- 1.6 g N/d) trimester was significant (P < 0.05). No differences were found in either 3-MeH or creatinine excretion between trimesters. CONCLUSIONS: These urinary nitrogen excretion and nitrogen retention data show that when the dietary supply remains constant, nitrogen balance increases toward the end of pregnancy, suggesting a more efficient use of dietary protein later in pregnancy. Urinary 3-MeH and creatinine excretion indicated no change in protein metabolism.