Table of Contents Summary 25 1. Introduction 33 1.1 Importance of complementary feeding for child health 33 1.2 Guiding principles for complementary feeding 34 1.3 Scope and organization of this report 34 2. Energy and nutrients needed from complementary foods 35 2.1 Energy, protein and lipids 35 2.2 Micronutrients 35 3. Methods 36 3.1 Sources searched and search strategy 36 3.2 Measurement of the treatment effect of interventions 36 3.3 Evaluation of methodological quality and level of evidence 37 3.4 Number of relevant studies identified 38 4. Findings of the systematic review 38 4.1 Types of intervention strategies 38 4.1.1 Educational interventions 38 4.1.2 Provision of food offering extra energy (with or without micronutrient fortification) 43 4.1.3 Micronutrient fortification of complementary foods 43 4.1.4 Increasing energy density of complementary foods through simple technology 46 4.1.5 Categorization of results by intervention strategy 46 4.2 Growth outcomes 46 4.2.1 Interventions using educational approaches 46 4.2.2 Interventions in which provision of complementary food was the only treatment 49 4.2.3 Interventions in which provision of complementary food was combined with another strategy, usually education for mothers 51 4.2.4 Interventions in which complementary foods were fortified with additional micronutrients 53 4.2.5 Interventions to increase energy density of complementary foods 55 4.3 Morbidity outcomes 55 4.3.1 Interventions using educational approaches 55 4.3.2 Interventions in which provision of complementary food was the only treatment 57 4.3.3 Interventions in which provision of complementary food was combined with another strategy, usually education for mothers 57 4.3.4 Interventions in which complementary foods were fortified with additional micronutrients 58 4.3.5 Interventions to increase energy density of complementary foods 59 4.4 Child development 61 4.4.1 Interventions in which provision of complementary food was the only treatment 61 4.4.2 Interventions in which complementary foods were fortified with additional micronutrients 62 4.5 Micronutrient intake 63 4.5.1 Intervention studies using educational approaches 63 4.5.2 Interventions in which provision of complementary food was the only treatment 64 4.5.3 Interventions in which provision of complementary food was combined with another strategy, usually education for mothers 64 4.5.4 Interventions in which complementary foods were fortified with additional micronutrients 65 4.5.5 Interventions to increase energy density of complementary foods 66 4.6 Iron status 66 4.6.1 Intervention studies using educational approaches 66 4.6.2 Interventions in which complementary food was provided, with or without another strategy such as education for mothers 68 4.6.3 Interventions in which commercially processed complementary foods were fortified with iron or multiple micronutrients 68 4.6.4 Interventions in which home fortification of complementary foods was the primary intervention 68 4.7 Zinc status 72 4.7.1 Interventions in which complementary foods were fortified with additional micronutrients, either commercially or with home fortification 72 4.8 Vitamin A status 72 4.8.1 Interventions in which complementary foods were fortified with additional micronutrients, either commercially or with home fortification 72 5. Discussion 75 5.1 Impact of complementary feeding interventions on growth 75 5.2 Impact of complementary feeding interventions on morbidity 77 5.3 Impact of complementary feeding interventions on child development 78 5.4 Impact of complementary feeding interventions on micronutrient intake 78 5.5 Impact of complementary feeding interventions on micronutrient status 78 5.6 Conclusions 79 Acknowledgments 82 References 82 Summary Introduction Complementary feeding interventions are usually targeted at the age range of 6–24 months, which is the time of peak incidence of growth faltering, micronutrient deficiencies and infectious illnesses in developing countries. After 2 years of age, it is much more difficult to reverse the effects of malnutrition on stunting, and some of the functional deficits may be permanent. Therefore, interventions that are effective at reducing malnutrition during this vulnerable period should be a high priority. Although several types of interventions can be targeted to this age range (e.g. micronutrient supplementation), a food‐based, comprehensive approach may be more effective and sustainable than programmes targeting individual nutrient deficiencies. For this review, a broad definition of ‘complementary feeding interventions’ is used so as to capture the full range of strategies that can be used. Scope and methods of the review The interventions described in this review generally include one or more components related to the Guiding Principles for Complementary Feeding of the Breastfed Child (PAHO/WHO 2003). The 10 guiding principles cover: (1) duration of exclusive breastfeeding and age of introduction of complementary foods; (2) maintenance of breastfeeding; (3) responsive feeding; (4) safe preparation and storage of complementary foods; (5) amount of complementary food needed; (6) food consistency; (7) meal frequency and energy density; (8) nutrient content of complementary foods; (9) use of vitamin‐mineral supplements or fortified products for infant and mother; and (10) feeding during and after illness. This review includes any relevant intervention that targeted children within the age range of 6–24 months. In some cases, the intervention may have included children older than 24 months, but in all studies at least some of the children were between 6 and 24 months. The assumption is that many of the children in these studies were breastfed, although a certain proportion will have terminated breastfeeding before 24 months. Although strategies for optimizing the duration of exclusive breastfeeding or increasing the total duration of breastfeeding may have a direct influence on several of the outcomes of interest, this review will not cover those strategies because another report will review those results. The primary outcomes of interest for this review include growth, morbidity and child development. Micronutrient intake and micronutrient status were also included as outcomes because of their link to these key functional outcomes. Studies that assessed the impact of complementary feeding interventions on feeding practices only were not included because of time constraints and because it has been demonstrated previously that appropriately designed interventions can have a positive impact on feeding practices (Caulfield et al. 1999). For most intervention strategies and outcomes, the literature search was focused on the period from 1996 to 2006, as the previous review by Caulfield et al. (1999) covered the period from 1970 to 1997. For certain interventions not covered in the previous review (i.e. using amylase to increase energy density and interventions focused on iron status outcomes), studies dating back to 1990 were included. Only studies conducted in developing countries were included. The search was conducted using electronic methods, inspection of websites of key private voluntary organizations and the bibliographies of published papers, and personal contacts. The two authors of this review independently assessed the quality of each of the reviewed studies, and those scored as 2– (non‐randomized studies with a high risk of bias) were not included in the tabulation of results. In total, 42 papers were included in the review. These papers report results from 29 efficacy trials and 13 effectiveness studies or programme reports from 25 developing countries. Interventions were considered efficacy trials if there was a high degree of assurance of delivery of the ‘treatment’, generally under carefully controlled research conditions (e.g. provision of a fortified complementary food with frequent follow‐up to assess adherence). Evaluations of interventions carried out in a programme setting, generally with less ability to control delivery of and adherence to ‘treatment’, were considered effectiveness studies. To compare growth (weight and length) results across studies (when these results were reported as means ± SD), we calculated the treatment effect size for each outcome of interest using the formula: When possible, the effect sizes for each outcome were averaged across interventions to obtain a rough estimate of overall impact. Effect size can be categorized as small (∼0.2), medium (∼0.5) or large (∼0.8). Interventions were grouped into five categories depending on the main strategy used: 1 education about complementary feeding as the main treatment, 2 complementary food or a food product offering extra energy (with or without added micronutrients) provided as the only treatment, 3 provision of food combined with some other strategy, usually education for mothers, 4 fortification of complementary foods (centrally processed fortified foods or home‐fortification products) with micronutrients (with no difference in energy provided to intervention vs. control groups), and 5 increased energy density and/or nutrient bioavailability of complementary foods through the use of simple technologies. Some studies had more than one intervention group and may thus be included in more than one of the categories. In these situations, only the results for the intervention groups that are relevant to the comparison in question are included in that section. Some of the interventions targeted only malnourished children, but most were aimed at all children in the target age range. Results Growth Nearly all of the studies assessed growth as an outcome. There were six efficacy trials and five effectiveness studies in which the main intervention strategy was education about complementary feeding. Taking these 11 studies together, educational interventions had a modest effect on weight (mean effect size = 0.28; range −0.06, 0.96) and linear growth (mean effect size 0.20, range 0.04, 0.64). The two educational interventions with the greatest impact on both weight and length gain (effect sizes of 0.34–0.96) were the projects in Peru (Penny et al. 2005) and China (Guldan et al. 2000). In both of these, a key message was to regularly provide an animal‐source food to the infant (chicken liver, egg or fish in Peru; egg in China). The other educational intervention with a relatively large impact on weight (though not on length) was a study in Bangladesh that targeted children with low weight‐for‐age at baseline (Roy et al. 2005). That intervention also promoted the home preparation of a complementary food mixture that included egg, meat or fish. There were seven efficacy trials and one effectiveness study in which the only intervention strategy was provision of complementary food (often fortified). The results were somewhat inconsistent: there was a positive impact in Ghana and Malawi but no impact in South Africa, Indonesia or Brazil. The overall mean effect size was 0.60 (range −0.02, 2.99) for weight and 0.47 (range −0.04, 1.81) for linear growth, but these effects are inflated by the results from Nigeria (Obatolu 2003) (effect sizes: weight = 2.99, length = 1.81). Excluding that study, the mean effect size was 0.26 (range −0.02, 0.57) for weight and 0.28 (range −0.04, 0.69) for length. For the combination of provision of complementary food with some other strategy (usually education), there were two efficacy trials and six effectiveness studies. With these eight studies combined, the average effect size for weight was 0.35 (range 0.18, 0.66) and that for linear growth was 0.17 (range 0, 0.32). Two studies specifically evaluated whether provision of food plus education was more effective than education alone (Bhandari et al. 2001; Roy et al. 2005). In India (Bhandari et al. 2001), the food plus education group gained 250 g more weight and 0.4 cm more than the control group during the 8‐month intervention, whereas the education‐only group gained only 90 g more than the control group and did not have any advantage in length gain. In Bangladesh (Roy et al. 2005), results for the education‐only group were intermediate between those of the food plus education and control groups. Thus, in these two settings the inclusion of a food supplement was more effective than education alone. The effect of fortification of complementary foods (with no difference in the amount of energy provided to intervention and control groups) on growth was evaluated in six efficacy trials, three of which involved home fortification using micronutrient supplements (powders or crushable tablets). The other three studies used cereal/legumes mixes or a milk formulation to which the micronutrients were added during processing. Only in the fortified‐milk study (conducted in India) was there a significant impact on growth. The average effect size for all six studies was 0.11 (range −0.22, 0.37) for weight and 0.12 (range −0.02, 0.45) for length. There were no effectiveness studies identified within this category. There were five efficacy trials in which the main strategy was aimed at increasing the energy density of the usual complementary food. Only two of these trials had a significant impact on growth (John & Gopaldas 1993; Moursi et al. 2003). In the other three (Mamiro et al. 2004; Hossain et al. 2005a; Owino et al. 2007), there was no increase in energy intake, so the lack of impact on growth is not surprising. The average effect size across all trials was 0.35 (range −0.13, 1.37) for weight and 0.23 (range −0.25, 0.71) for linear growth. Figures 1 and 2 compare the effect sizes for growth across each category of intervention. The average effect sizes are in the small to medium range, which is in agreement with estimates from the previous review of interventions completed between 1970 and 1997 [effect size generally 0.10–0.50 (Caulfield et al. 1999)]. 1 Effect sizes of different intervention strategies for growth in weight. ED = education about child feeding alone; FD = provision of complementary food alone; FD+ED = provision of complementary food plus some other strategy, usually education; FT = Fortification of complementary foods; EN = increased energy density. Each curve shows the mean effect size and range (minimum and maximum). The study by Obatolu (2003) was an outlier (effect size for weight at 18 months = 2.99) and was thus excluded. 2 Effect sizes of different intervention strategies for linear growth. ED = education about child feeding alone; FD = provision of complementary food alone; FD+ED = provision of complementary food plus some other strategy, usually education; FT = fortification of complementary foods; EN = increased energy density. Each curve shows the mean effect size and range (minimum and maximum). The study by Obatolu (2003) was an outlier (effect size for length at 18 months = 1.81) and was thus excluded. Morbidity Only 10 of the intervention studies included data on morbidity outcomes. In most of these, there were no significant effects on morbidity. Most studies included morbidity as a secondary outcome and were not designed or powered to detect differences in morbidity. Two of the educational interventions showed a beneficial effect: a reduction in diarrhoea in Brazil (Vitolo et al. 2005) and a reduction in upper respiratory infection in Vietnam (Schroeder et al. 2002). The fortified‐milk study in India demonstrated a significant reduction in both diarrhoea and acute lower respiratory illness (Sazawal et al. 2007), and a study evaluating home fortification with a micronutrient powder (‘Sprinkles™’) in Pakistan showed beneficial effects on diarrhoea and fever (Sharieff et al. 2006). However, in three studies the interventions were associated with increased symptoms of morbidity. This was evident in food supplementation interventions in Bangladesh [during the first 2 months of the intervention (Roy et al. 2005)] and in India (Bhandari et al. 2001) and in an energy‐density intervention in Congo (Moursi et al. 2003). In India, the adverse effects on fever and dysentery could have been due to the reduction in breastfeeding that occurred in the intervention group. Unhygienic preparation and storage of complementary foods is another possible explanation for adverse effects of these interventions on morbidity. Behavioural development Only four studies, all efficacy trials, included data on behavioural development. The provision of a fat‐based fortified food product or micronutrients alone improved gross motor development in Ghana (Adu‐Afarwuah et al. 2007) but these types of interventions did not have any significant effect on developmental outcomes in South Africa (Oelofse et al. 2003) or India (Dhingra et al. 2004). Positive results of supplementation with extra energy in Indonesia were seen only in a subgroup (Pollitt et al. 2002). Micronutrient intake Only a few studies reported data on iron, zinc and vitamin A intakes. Education for mothers significantly increased child iron intake in Malawi, India and Peru, but did not have any significant effect on intakes in Brazil. Taking those four studies together, the intervention increased iron intake from complementary foods by 24% (range −7%, 60%) and zinc intake by 26% (range 9%, 53%). Despite those increases, mean iron and zinc intake from complementary foods was still well below recommended intakes in some sites. In Brazil (Santos et al. 2005) a large‐scale food supplementation programme failed to have an impact on intakes of these three micronutrients. There was also no impact of traditional processing of complementary foods in Tanzania (Mamiro et al. 2004). The largest impact on micronutrient intakes resulted from fortification strategies, which increased iron intake by 145–207% in Mexico and Ghana, zinc intake by 201–271% in Ecuador and Ghana, and vitamin A intake by 107% to more than 2300% in Ecuador and Ghana. Anaemia and iron status Four studies of educational interventions included data on anaemia and/or iron status. In India and China there was an increase in mean haemoglobin but in Nicaragua and Brazil there was no significant effect. The difference in impact across studies could be due to the specificity of the messages regarding enhancement of iron intake in the two former studies, compared with the latter two projects. Overall, for these four studies the average impact was an increase of 4 g L−1 in mean haemoglobin and a reduction in the prevalence of anaemia of 5 percentage points. In 12 studies, the target group was provided with a complementary food that was fortified with iron (and sometimes other micronutrients as well). The comparison group received either no additional food (five studies: two efficacy trials and three programme evaluations), or an unfortified complementary food (seven efficacy trials). For the former group of five studies, the average impact was an increase of 4 g L−1 in mean haemoglobin and a reduction in the prevalence of anaemia of 13 percentage points. For the latter group of seven studies, the average effect was an increase of 6 g L−1 in mean haemoglobin and a reduction in the prevalence of anaemia of 17 percentage points. Another seven studies (five efficacy trials, two programme evaluations) evaluated the effect of home fortification of complementary foods using powders, crushable tablets or fat‐based products. Taking these seven studies together, the average impact was an increase of 8 g L−1 in mean haemoglobin and a reduction in the prevalence of anaemia of 21 percentage points. Some of the above studies included direct assessments of iron status, such as ferritin values. In most cases, the impact on the prevalence of iron deficiency was greater than the impact on anaemia, indicating that other factors such as malaria contribute to the persistently high rates of anaemia in certain populations. Zinc status Only five studies reported plasma zinc concentrations, all of which involved evaluation of a fortified complementary food (three efficacy trials, one programme evaluation), or a home‐fortification product (efficacy trial). The fortified foods provided 3–6.5 mg day−1 zinc, and the daily home‐fortification ‘foodlet’ (crushable tablet) provided 10 mg day−1. In the four studies using fortified foods, none demonstrated a significant difference between intervention and control groups in mean plasma zinc concentration or the percentage of children with low plasma Zn. In the foodlet intervention trial in South Africa, the group receiving daily micronutrients had significantly higher plasma zinc than the placebo group (Smuts et al. 2005). Overall, these results indicate that complementary foods fortified with multiple micronutrients, including zinc, have little impact on plasma zinc concentration, perhaps because of the relatively low bioavailability of zinc when consumed with cereal‐based or cereal/legume blend foods. Vitamin A status Seven intervention studies to evaluate the impact of a fortified complementary food (three efficacy trials, two programme evaluations) or home‐fortification products (two efficacy trials) included data on vitamin A status. There was a significant impact on mean serum vitamin A concentration in four of the five interventions using fortified complementary foods, and a reduction in the incidence of vitamin A deficiency in the two studies (of these five) that evaluated this outcome. There was no significant impact on serum vitamin A concentration in the two studies using home‐fortification products, which the investigators attributed to widespread participation in vitamin A supplementation programmes that occurred during the study time period. Taken together, these seven studies indicate that complementary foods fortified with vitamin A can reduce the incidence of vitamin A deficiency (by an average of ∼−13 percentage points in the two studies that reported this), although this impact may be obscured by concurrent vitamin A supplementation programmes. Conclusions The results of this review indicate that there is no single universal ‘best’ package of components in complementary feeding interventions because the needs of the target population vary greatly. The impact of such interventions is thus context specific, and depends on factors such as the initial prevalence of malnutrition, the degree of household food insecurity, the energy density of traditional complementary foods and the availability of micronutrient‐rich local foods. Child growth was the most common outcome measured, but it may not be the most sensitive indicator of benefit because of other constraints that limit the extent to which a child's growth (particularly height) can respond to post‐natal interventions. The impact of these interventions on child growth was mixed. When the primary approach was education about child feeding, interventions that included a strong emphasis on feeding nutrient‐rich animal‐source foods were more likely to show an effect. When a complementary food was provided, with or without concurrent strategies such as nutrition education, the studies in Africa and South Asia generally showed positive effects, while those in other regions were more variable. This may be related to the relatively high prevalence of food insecurity in Africa and South Asia. In such contexts, providing additional food – not just education – may facilitate the ability of families to follow complementary feeding guidelines. In several studies, the impact of providing a complementary food, in combination with nutrition education, was evident only in the younger children. This underscores the importance of beginning complementary feeding programmes during infancy, when nutrient needs relative to energy intake are the highest and the ability of the child to respond to a nutritional intervention is the greatest. Because most interventions in which a complementary food was provided used fortified foods, it is not possible to determine whether the positive effects on growth are due to greater energy/protein/fat intake, greater micronutrient intake, or the combination. It is noteworthy that the interventions in which micronutrient fortification was the sole component (i.e. comparisons of fortified vs. unfortified complementary foods, or evaluations of home fortification) generally had little or no effect on growth. Further research on the biological mechanisms underlying growth effects, including the potential roles of milk protein and essential fatty acids, is needed. Increasing the energy density of complementary foods may have a positive effect on growth when the traditional complementary food has a low energy density and infants are unable to adequately compensate by consuming a higher volume or being fed more frequently. However, before including this strategy in a complementary feeding programme, it is advisable to first demonstrate that increasing energy density of the traditional food will actually result in increased total daily energy intake (including energy intake from breastmilk). It should be noted that increasing energy density will not necessarily result in adequate micronutrient intake, so this strategy should be accompanied by other efforts to improve dietary adequacy. The potential for an impact on growth appears to be greater with interventions using key educational messages, provision of complementary food with or without fortification, or increased energy density of complementary foods than with interventions based on fortification alone. Although the effect sizes for growth were generally modest (0.1–0.5), the potential impact is larger (0.5–0.6) if programmes are optimally designed and implemented. Furthermore, the impact on the lower tail of the distribution – that is, on stunting rates – could be considerably larger than the effect on the mean height z‐score. In general, effect sizes for growth of interventions providing complementary foods were greater for efficacy trials than for programmes. This is not surprising, given the logistical challenges of ensuring consistent delivery of food (and education) in large‐scale programmes. Some of the complementary feeding interventions reviewed had a beneficial impact on morbidity rates, but there is the potential for adverse effects of strategies such as food supplementation and increased energy density. This may be due to excessive displacement of breastmilk and/or unhygienic preparation and storage of complementary foods. This highlights the need to couple complementary feeding interventions with counselling regarding continued breastfeeding, responsive feeding and hygienic practices. There is very little information on the impact of complementary feeding interventions on behavioural development, but recent studies in infants have yielded promising results. It is important to include assessments of behavioural development in such evaluations, as these outcomes may be more sensitive to improvements in child nutrition than outcomes such as growth and morbidity. With regard to micronutrient intake, the results of educational interventions indicate that it is difficult to achieve adequate iron intake from unfortified local foods at 6–12 months of age. Fortification (either processed complementary foods or home fortification) is the most feasible option in most circumstances given the cost of iron‐rich foods (such as liver or meat). Adequate zinc and vitamin A intakes can be achieved from local foods, but this requires very careful attention to dietary choices. Fortification can help ensure zinc and vitamin A intakes when nutrient‐rich local foods are costly or unavailable (e.g. seasonally). The results also indicate that fortification can be highly effective at improving iron and vitamin A status. Although this could be accomplished by other strategies, such as iron or vitamin A supplementation, using complementary foods as the vehicle may be less risky [given recent concerns about adverse effects of iron supplements in certain situations (WHO & UNICEF 2007)] and more acceptable to caregivers. Further research is needed to understand why zinc‐fortified foods have generally little effect on plasma zinc concentrations. Complementary feeding interventions, by themselves, cannot change the underlying conditions of poverty and poor sanitation that contribute to child malnutrition. They need to be implemented in conjunction with a larger strategy that includes improved water and sanitation, better health care and adequate housing. Nonetheless, the results of this review indicate that carefully designed programmes that include pre‐tested educational messages provided through multiple channels, with fortified foods or home‐fortification products made available depending on the needs of the target population, can substantially improve growth and micronutrient status and may also reduce morbidity and enhance behavioural development. The key challenge is how to implement high‐quality programmes that are sustainable when delivered on a large scale.
Table of Contents Summary 119 1. Introduction 119 1.1 The gastrointestinal ecosystem 119 1.2 Groups of intestinal parasitic worms that infect humans 121 1.2.1 Flukes or trematodes 121 1.2.2 Tapeworms or cestodes 122 1.2.3 Roundworms or nematodes 123 1.3 How worms may affect human nutrition and growth 126 1.4 Design of studies estimating the impact of worms 128 1.5 Aims 128 2. Factors affecting the impact of intestinal worms 128 2.1 Species of intestinal worm 128 2.2 Prevalence of infection 129 2.3 Number and distribution of worms 132 2.4 Duration of infection 135 2.5 Rate of reinfection 135 2.6 Summary 136 3. Factors affecting the impact of treatment 137 3.1 Study design: controls and randomization 138 3.2 Anthelmintic drugs 138 3.3 Intervals between treatments 141 3.4 Duration of follow‐up 142 3.5 Outcomes measured and the need for controls 142 3.6 Initial nutritional status 143 3.7 Age of subjects 144 3.8 Remedial therapy after treatment 144 3.9 Summary 145 4. Aims and methods of the meta‐analysis 145 4.1 Search terms 145 4.2 Inclusion criteria 146 4.3 Exclusion criteria 147 4.4 Meta‐analysis 147 5. Results of the meta‐analysis 147 5.1 Geographic origin of studies 150 5.2 Estimates of effects 150 5.3 The figures and how to interpret them 150 5.4 Sources of error or bias 150 6. Discussion 153 6.1 Magnitude of effects 153 6.2 Treatment alone is not enough 159 6.3 The Cochrane Collaboration Review 161 6.4 Characteristics of an ideal study 162 6.5 Implications for programmes 163 6.6 Conclusions 166 Acknowledgements 167 References 167 Appendix: Summary of papers identified for the review 177 Summary More than a half of the world's population are infected with one or more species of intestinal worms of which the nematodes Ascaris lumbricoides, Trichuris trichiura and the hookworms are the most common and important in terms of child health. This paper: (1) introduces the main species of intestinal worms with particular attention to intestinal nematodes; (2) examines how such worms may affect child growth and nutrition; (3) reviews the biological and epidemiological factors that influence the effects that worms can have on the growth and nutrition of children; (4) considers the many factors that can affect the impact of treatment with anthelmintic drugs; (5) presents the results of a meta‐analysis of studies of the effect of treating worm infections on child growth and nutrition; (6) discusses the results in terms of what is reasonable to expect that deworming alone can achieve; (7) describes some important characteristics of an ideal study of the effects of deworming; and (8) comments on the implications for programmes of recommendations concerning mass deworming.
The aim of the present study was to examine the relative validity of foods and nutrients calculated by a new food frequency questionnaire (FFQ) in the Norwegian Mother and Child Cohort Study (MoBa). Reference measures were a 4‐day weighed food diary (FD), a motion sensor for measuring total energy expenditure, one 24‐h urine collection for analysis of nitrogen and iodine excretion, and a venous blood specimen for analysis of plasma 25‐hydroxy‐vitamin D and serum folate. A total of 119 women participated in the validation study, and 112 completed the motion sensor registration. Overall, the level of agreement between the FFQ and the FD was satisfactory, and significant correlations were found for all major food groups and for all nutrients except vitamin E. The average correlation coefficient between the FFQ and the FD for daily intake was 0.48 for foods and 0.36 for nutrients, and on average, 68% of the participants were classified into the same or adjacent quintiles by the two methods. Estimated total energy expenditure indicated that under‐reporting of energy intake was more extensive with the FD than with the FFQ. The biological markers confirmed that the FFQ was able to distinguish between high and low intakes of nutrients, as measured by vitamin D, folate, protein and iodine. This validation study indicates that the MoBa FFQ produces reasonable valid intake estimates and is a valid tool to rank pregnant women according to low and high intakes of energy, nutrients and foods.
The aim of this article is to describe the main methodological challenges in the monitoring of dietary intake in the Norwegian Mother and Child Cohort Study (MoBa), a pregnancy cohort aiming to include 100 000 participants. The overall challenge was to record dietary patterns in sufficient detail to support future testing of a broad range of hypotheses, while at the same time limiting the burden on the participants. The main questions to be answered were: which dietary method to choose, when in pregnancy to ask, which time period should the questions cover, which diet questions to include, how to perform a validation study, and how to handle uncertainties in the reporting. Our decisions were as follows: using a semi‐quantitative food frequency questionnaire (FFQ) (in use from 1 March 2002), letting the participants answer in mid‐pregnancy, and asking the mother what she has eaten since she became pregnant. The questions make it possible to estimate intake of food supplements, antioxidants and environmental contaminants in the future. Misreporting is handled by consistency checks. Reports with a calculated daily energy intake of 20 MJ day−1 are excluded, about 1% in each end of the scale. A validation study confirmed that the included intakes are realistic. The outcome of our methodological choices indicates that our FFQ strikes a reasonable balance between conflicting methodological and scientific interests, and that our approach therefore may be of use to others planning to monitor diet in pregnancy cohorts.
The objective of this study was to examine how breastfeeding behaviours, perceptions and experiences vary by race/ethnicity among a low‐income sample in the USA. Bilingual interviewers conducted a cross‐sectional telephone survey of 767 white, African American or Hispanic mothers who received the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Rates of breastfeeding initiation and duration varied by race/ethnicity. Hispanic mothers were more likely to initiate breastfeeding than African American (91% vs. 65%) or white (61%) mothers. Hispanic mothers breastfed longer (mean 5 months) than either African American (mean 3.5 months) or white (mean 3 months) mothers. The most common reason for not breastfeeding was fear of difficulty or pain during breastfeeding (35.6%). Among mothers who did not initiate breastfeeding, African American and white mothers were more likely than Hispanic mothers to report perceptions of breastfeeding difficulty or pain, and Hispanic mothers were more likely than African American and white mothers to report perceptions of infant breast rejection. The most common reason reported for breastfeeding cessation was not having enough milk (23.4%). Hispanic mothers were more likely than African American and white mothers to cite perceptions of milk insufficiency and infant breast refusal than concerns regarding breast discomfort or pain. African American mothers were more likely than white mothers to report cessation to return to work. In conclusion, while breastfeeding initiation rates approach Healthy People 2010 goals, breastfeeding duration remains far below these goals. Race/ethnicity differences in experiences related to breastfeeding cessation suggest that culturally sensitive breastfeeding interventions are necessary.
The aim of this paper is to investigate whether the lower rate of breastfeeding at 6 months by overweight and obese mothers is primarily due to these women giving up breastfeeding in the first week postpartum using a cross‐sectional population survey. The sample is children from the infant cohort (about 12 months of age) of Wave 1 (2004) of the Longitudinal Study of Australian Children for whom breastfeeding and maternal information were available (n = 3075). Definitions used: normal‐weight body mass index (BMI, kg/m2) 20 to <25, overweight BMI 25 to <30, obese BMI ≥30. Breastfeeding initiation was 95.1% for normal‐weight women, 92.8% for overweight women and 87.1% for obese women. At 6 months, 64% of normal‐weight women were breastfeeding, compared with 54% of overweight and 44% of obese women. On multivariate analysis, for women who initiated breastfeeding, overweight women had an odds ratio (OR) of 1.52 [95% confidence interval (CI) 1.02, 2.28] and obese women had an OR of 2.54 (95% CI 1.70, 3.79) of stopping breastfeeding by 1 week compared with normal‐weight women (adjusted for maternal age, education, smoking, level of socio‐economic disadvantage, caesarean birth, admission to special care nursery). For women who breastfed for at least 1 week, overweight women had an adjusted OR of 1.26 (1.04, 1.53) and obese women had an adjusted OR of 1.38 (1.10, 1.73) of ceasing to breastfeed before 6 months, compared with normal‐weight women. In conclusion, among overweight/obese women who initiate breastfeeding, higher rates of cessation of breastfeeding in both the immediate postpartum period and in the first 6 months contribute to the shorter duration.
Table of Contents Summary 86 1. Background 88 1.1 History and development of growth monitoring programmes 88 1.2 Objectives of growth monitoring 89 2. Expected benefits of growth monitoring and growth promotion 90 3. Objectives of this review 91 4. Methodology 91 5. Evidence of effectiveness of growth monitoring programmes 91 5.1 Nutritional status and mortality of young children 91 5.1.1 Studies before 1990 91 5.1.2 Studies since 1990 96 5.2 Utilization of primary health services 103 6. Quality of implementation 104 7. Caregivers' knowledge and understanding of growth charts 105 8. Empowerment and community mobilization 106 9. Coverage and attendance 107 10. Potential consequences if withdrawn 108 11. Feasibility and conditions under which growth monitoring and promotion can be expected to work 108 12. Cost‐effectiveness 109 13. Potential adverse consequences 109 14. Policy considerations and recommendations 110 References 113 Summary The rationale for growth monitoring and promotion is persuasive but even in the 1980s the appropriateness of growth monitoring programmes was being questioned. The concerns centred largely around low participation rates, poor health worker performance and inadequacies in health system infrastructure that constrained effective growth‐promoting action. More recently there has been a call for a general review of the impact of large‐scale growth monitoring and promotion programmes to determine if the investments are justified. The launch of the new World Health Organization growth standard and charts has been a timely reminder of this debate. It is within this context that this review has been undertaken: the main purpose is to analyse the evidence that growth monitoring programmes are effective in conferring measurable benefits to the children for whom growth charts are kept. The benefits considered here are improved nutritional status, increased utilization of health services and reductions in mortality. There is evidence from small‐scale studies in Nigeria, Jamaica, India (Narangwal and Jamkhed), and from large programmes in Tanzania (Iringa), India (Tamil Nadu Integrated Nutrition Project), Madagascar and Senegal that children whose growth is monitored and whose mothers receive nutrition and health education and have access to basic child health services have a better nutritional status and/or survival than children who do not. There is tentative evidence from a large‐scale programme in Brazil (Ceara) that participation in growth monitoring confers a significant benefit on nutritional status independent of immunization and socio‐economic status. There is evidence from India (Integrated Child Development Services) and Bangladesh (Bangladesh Rural Advancement Committee and Bangladesh Integrated Nutrition Project) that growth monitoring has little or no effect on nutritional status in large‐scale programmes with weak nutrition counselling. There is evidence from Tamil Nadu in a randomized trial that when mothers are visited fortnightly at home and have unhurried counselling, no additional benefit accrues from the visual depiction of growth on a chart. There is some evidence that growth monitoring can improve utilization of health services. Although there is no unequivocal evidence that growth monitoring is beneficial per se, it was perceived to be beneficial by the investigators of several of the studies described in this review. Growth monitoring can provide an entry point to preventive and curative health care and was an integral part of programmes that were associated with significant reductions in malnutrition and mortality. Good nutrition counselling is paramount for growth promotion and is often done badly. Effort must be made to improve this and provide age‐appropriate advice to achieve exclusive breastfeeding and appropriate complementary feeding, irrespective of decisions about growth monitoring. This review highlights the paucity of rigorous trials to determine the impact of growth monitoring separately from the impact of growth promotion. There is no controversy about the need for growth‐promotion activities, and weighing children is desirable to assess health and nutrition status. The debatable question is whether weights need to be monitored monthly and plotted on a chart. Even if there is a policy for growth monitoring, if a child has grown well in the first year of life then it would appear that little is gained by monitoring weight beyond the age of 12 months, and that the time spent monitoring older children might be better spent improving the counselling given to caregivers of infants. Growth monitoring may not be the best use of limited resources in countries with weak economies and inadequate health budgets: a limited package of health and nutrition interventions including good nutrition counselling may be preferable, aiming for good coverage and effective health worker performance, and prioritizing infants and children <18 months of age. Two of the potential strengths of growth monitoring are that it provides frequent contact with health workers and a conduit to child health interventions. Taking into account the evidence from recent nutrition education interventions in India and Peru that used multiple delivery channels within routine health services, possible options to consider for the future are: • If growth monitoring is not in place, then focus efforts on growth‐promotion activities and consider counselling caregivers intensively at all child health contacts and through home visits by community health workers or volunteers. Where possible chart weights at birth, immunization (6, 10, 14 weeks and 9 months), vitamin A distribution and sick‐child visits. Follow up and counsel any whose weight is faltering and those with a weight‐for‐age <−2 SD. • Where growth monitoring exists but the coverage is low or there is little potential for improvement, then consider abandoning it and re‐focus efforts on growth‐promotion activities as described above. • Where growth monitoring and promotion programmes currently exist and there is potential for improvement, then maximize their potential, strengthen the nutrition counselling elements, combine growth monitoring with other health intervention channels such as immunization for the convenience of caregivers, and ensure consistent message delivery. Target younger children and use the time gained to improve services. Monitor weight until 12 months of age. If there are episodes of growth faltering, continue to monitor until 18 months. Where cultural traditions and conditions are favourable, use growth monitoring additionally for community mobilization to address underlying socio‐economic and other causes of poor nutrition and health. Scaling up from successful small‐scale growth monitoring and promotion programmes to effective national programmes will require political commitment, investment, extensive capacity building and strengthening of health systems. Training, supervision and support will need to be improved if health workers are to be equipped with the necessary knowledge and communication skills to promote healthy growth. Impact will be related to coverage, intensity of contact, health worker performance, adequacy of resources and the ability and motivation of families to follow advice.
Table of Contents Summary 5 Background 6 Methods and search strategy 6 The scale‐up process 7 Issues that need to be addressed while scaling up a programme for exclusive breastfeeding 7 Conclusions 13 Acknowledgements 14 References 14 Appendix 1 18 Appendix 2 22 Summary Interventions to promote exclusive breastfeeding have been estimated to have the potential to prevent 13% of all under‐5 deaths in developing countries and are the single most important preventive intervention against child mortality. According to World Health Organization and United Nations Children Funds (UNICEF), only 39% infants are exclusively breastfed for less than 4 months. This review examines programme efforts to scale up exclusive breastfeeding in different countries and draws lesson for successful scale‐up. Opportunities and challenges in scaling up of exclusive breastfeeding into Maternal and Child Health programmes are identified. The key processes required for exclusive breastfeeding scale‐up are: (1) an evidence‐based policy and science‐driven technical guidelines; and (2) an implementation strategy and plan for achieving high exclusive breastfeeding rates in all strata of society, on a sustainable basis. Factors related to success include political will, strong advocacy, enabling policies, well‐defined short‐ and long‐term programme strategy, sustained financial support, clear definition of roles of multiple stakeholders and emphasis on delivery at the community level. Effective use of antenatal, birth and post‐natal contacts at homes and through community mobilization efforts is emphasized. Formative research to ensure appropriate intervention design and delivery is critical particularly in areas with high HIV prevalence. Strong communication strategy and support, quality trainers and training contributed significantly to programme success. Monitoring and evaluation with feedback systems that allow for periodic programme corrections and continued innovation are central to very high coverage. Legal framework must make it possible for mothers to exclusively breastfeed for at least 4 months. Sustained programme efforts are critical to achieve high coverage and this requires strong national‐ and state‐level leadership.
Responsive complementary feeding, whereby the mother feeds her child in response to child cues of hunger state and psychomotor abilities, is a problem in some countries, and likely contributes to malnutrition. Interventions are needed to evaluate whether promoting responsive feeding would add any benefit. Using a cluster randomized field trial, we evaluated a six‐session educational programme that emphasized practice of two key behaviours, namely child self‐feeding and maternal responsiveness. One hundred mothers and their 12‐ to 24‐month‐olds attended the sessions as part of village clusters randomly assigned to the intervention group. A similar number of controls received sessions on foods to feed and nutritional disorders. Outcomes assessed at pre‐test, 2‐week post‐intervention and again 5‐months post‐intervention included weight, mouthfuls of food taken, self‐feeding and maternal responsiveness. Research assistants, blind to group assignment, observed and coded mother and child behaviours during the midday meal. Secondary measures included foods fed and feeding messages recalled. Analysis was based on intention to treat and accounted for clustering. Only 10% of each group was lost to follow‐up. Weight (d = 0.28), weight gain (d = 0.48) and child self‐feeding (d = 0.30) were significantly higher in the responsive feeding group. Mouthfuls of food eaten and maternal responsiveness were not significantly increased by the intervention. Mothers in the intervention gave their children more vegetables, and spontaneously recalled more feeding messages at the 5‐month follow‐up. These results provide evidence that self‐feeding and weight gain can improve by targeting specific behaviours, while maternal responsiveness may require more intensive strategies.
The objective of the study was to investigate the association between maternal common mental disorder (CMD) and infant growth in rural Malawi. A cross‐sectional study was conducted at a district hospital child health clinic. Participants were consecutive infants due for measles vaccination, and their mothers. Mean infant weight‐for‐age and length‐for‐age z‐scores were compared between infants of mothers with and without CMD as measured using the self‐reporting questionnaire (SRQ). Of 519 eligible infants/mothers, 501 were included in the analysis. Median infant age was 9.9 months. 29.9% of mothers scored 8 or above on the SRQ indicating CMD. Mean length‐for‐age z‐score for infants of mothers with CMD (−1.50 SD 1.24) was significantly lower than for infants of mothers without CMD (−1.11 SD 1.12) Student's t‐test: P = 0.001. This association was confirmed in multivariate analysis. Mean weight‐for‐age z‐score for infants of mothers with CMD (−1.77 SD 1.16) was lower than for infants of mothers without CMD (−1.59 SD 1.09) but this difference was not significant on univariate (Student's t‐test: P = 0.097) or multivariate analysis. The study demonstrates an association between maternal CMD and infant growth impairment in rural sub‐Saharan Africa.
In conjunction with other health professionals, doctors believe they play an important role in promoting breastfeeding to women. Although many have positive breastfeeding attitudes, significant knowledge deficits often limit their capacity to effectively encourage, support and assist breastfeeding women and their infants. Personal breastfeeding experience (of self or partner) may be the main source of breastfeeding knowledge and skill development and is related to improved knowledge, more positive attitudes and greater confidence. This paper describes the relationship between the cumulative length of personal breastfeeding experience and the breastfeeding knowledge and attitudes of a cohort of Australian general practice (GP) registrars, as well as their confidence and perceived effectiveness assisting breastfeeding women. The Australian Breastfeeding Knowledge and Attitude Questionnaire containing demographic items, a 20‐item attitude scale and a 40‐item knowledge scale was distributed between February and May 2007 to Australian GP registrars in their final year of training. Participants with more than 52‐week cumulative personal (self or partner) breastfeeding experience had the highest mean knowledge score, had more positive attitudes, and were more confident and effective than all other participants. Parents with limited personal experience (≤26 weeks) had the poorest breastfeeding attitudes and their knowledge base was similar to participants with no personal experience. Confidence and perceived effectiveness when assisting breastfeeding women rose with increasing cumulative breastfeeding experience. Personal breastfeeding experience per se does not guarantee better breastfeeding knowledge or attitudes although increasing length of experience is related to higher knowledge, attitude, confidence and perceived effectiveness scores.
In Cambodia, the energy and nutrient densities of the traditional rice‐based complementary diets used for infant feeding are very low. Whether the adequacy improves after the first year of life is uncertain. Therefore, we examined the feeding practices and the energy and nutrient intakes from non‐breastmilk foods (NBMFs) of two groups: partially breastfed (PBF) (n = 41) and non‐breastfed (NBF) (n = 210) stunted toddlers aged 12–42 months from poor villages in Phnom Penh, Cambodia. Intakes of NBMFs were estimated from 24‐h recalls and a specially constructed Cambodian food composition table. All the toddlers were breastfed initially, but more than 50% received complementary foods before 6 months of age (mainly rice porridge). Many PBF toddlers received mixed feeding and were often bottle‐fed diluted sweetened condensed milk. Unresponsive feeding was widespread. Inappropriate snacks, such as crisps, were the major source of energy, calcium, iron, zinc and vitamin A from NBMFs for the PBF group, and energy and iron for the NBF group. The snacks were often purchased and consumed without any adult supervision. For both groups, intakes of energy, calcium, iron and zinc were consistently below recommendations, as a result of the low micronutrient density of NBMFs and the small amounts fed per feeding. Increasing intakes of animal‐source foods and dark‐green and yellow fruits and vegetables would enhance micronutrient densities, although this may be neither feasible nor sufficient to overcome the existing deficits. Instead, the feasibility of micronutrient fortification of the rice‐based diets of Cambodian toddlers should be explored.
Newborn mortality accounts for about one‐third of deaths in children under five. Neglecting this problem may undermine the fourth Millennium Development Goal of reducing child mortality by two‐thirds by 2015. This study was conducted in Tanzania, where an estimated 32/1000 infants die within the first 28 days. Our objective was to describe newborn care practices and their potential impact on newborn health. We interviewed two purposive samples of mothers from Pemba Island, a predominantly Muslim community of Arab‐African ethnicity, and one of Tanzania's poorest. The first sample of mothers (n = 12) provided descriptive data; the second (n = 26) reported actual practice. We identified cultural beliefs and practices that promote early initiation of breastfeeding and bonding, including ‘post‐partum seclusion’. We also identified practices which are potentially harmful for newborn health, such as bathing newborns immediately after delivery, a practice motivated by concerns about ‘ritual pollution’, which may lead to newborn hypothermia and premature breast milk supplementation (e.g. with water and other fluids) which may expose newborns to pathogens. Some traditional practices to treat illness, such as exposing sick newborns to medicinal smoke from burning herbs, are also of concern. It is unclear whether the practice of massaging newborns with coconut oil is harmful or beneficial. Interventions to reduce neonatal mortality need to identify and address the cultural rationales that underlie negative practices, as well as reinforce and protect the beliefs that support positive practices. The results suggest the need to improve use of health services through improving health worker communication skills and social management of patients, as well as by lowering healthcare costs.
This review aimed to identify interventions to promote breastfeeding or breast milk feeding for infants admitted to the neonatal unit. The medical electronic databases were searched for papers listed between 1990 and June 2005 which had breastfeeding or breast milk as an outcome and which targeted infants who had been admitted to a neonatal unit, thus including the infant and/or their parents and/or neonatal unit staff. Only papers culturally relevant to the UK were included resulting in studies from the USA, Canada, Europe, Australia and New Zealand. This search was updated in December 2007 to include publications up to this date. We assessed 86 papers in full, of which 27 ultimately fulfilled the inclusion criteria. The studies employed a range of methods and targeted different aspects of breastfeeding in the neonatal unit. Variations in study type and outcomes meant that there was no clear message of what works best but skin‐to‐skin contact and additional postnatal support seemed to offer greater advantage for the infant in terms of breastfeeding outcome. Galactogogues for mothers who are unable to meet their infants’ needs may also help to increase milk supply. Evidence of an effect from other practices, such as cup‐feeding on breastfeeding was limited; mainly because of a lack of research but also because few studies followed up the population beyond discharge from the unit. Further research is required to explore the barriers to breastfeeding in this vulnerable population and to identify appropriate interventions to improve breastfeeding outcomes.
The recent release of new growth charts by the World Health Organization (WHO) heralds a fresh understanding of what constitutes normal infant growth and development. The Multicenter Growth Reference Study that underpins these new growth standards ‘establish[es] breastfed infants as the normative model for growth and development’. This is in contrast to past practice, which treated breastfeeding as the optimal, rather than the normal, way to feed babies. This idealization of breastfeeding has been counterproductive, because it has reinforced a perception that formula feeding is the standard way of feeding babies. It is, therefore, suggested that breastfeeding promotion and education programmes should abandon the ‘breast is best’ message in favour of messages that normalize breastfeeding, and that future research ought to use infants breastfed according to WHO recommendations as the norm reference or control group in every instance.
This study investigated whether perceptions of parenting behaviours predict young adolescents' nutritional intake and body fatness. The randomly selected study sample consisted of 106 13–15 years olds from Houston Metropolitan Statistical Area. Parenting style variables were created by cluster analysis and factor analysis. A two‐cluster solution for both maternal and paternal parenting style represented authoritative vs. non‐authoritative parenting. Two parenting dimension factors derived were maternal/paternal nurturing and control. For adolescents' energy and nutrient intake, greater maternal nurturing appeared to be most beneficial given its association with lower consumption of total kilocalorie and lower saturated fat intake. Paternal nurturing was associated with lower sodium intake, whereas paternal control predicted lower percentage of kilocalories from carbohydrate and percentage Dietary Reference Intake for dietary fibre, and greater percentage of kilocalories from total fat. Maternal authoritative parenting and lower maternal control over their adolescents may have protective effects against having heavier and fatter adolescents given their associations with adolescents' body weight, sub‐scapular skinfold, waist circumference, body mass index, and the tendencies of being at risk of overweight and being overweight. None of paternal parenting styles or dimensions appeared to be significantly related to adolescents' body fatness.
The usefulness of routine prenatal weight measurements in predicting pregnancy outcomes is still a controversial issue. Comparisons among studies and the interpretation of research findings are complicated due to the variety of indicators applied to express maternal weight changes during and after pregnancy. A review of literature was conducted to clarify the definitions and examine the strengths and limitations of methods for measuring gestational weight gain (WG) and postpartum weight changes. The reasons for weak correlations or non‐significant associations between gestational WG and maternal and neonatal outcomes were probably owing to poor quality of obstetrics records and selection of wrong indicators to compute gestational WG. The choice of an indicator depends on clinical and research purpose, availability and reliability of data and cost. Considering the health implication of gestational WG, it is necessary to take into account the measurements used as initial and final weight, accuracy of gestational age estimation and the inclusion of fetal weight as part of maternal WG. Regardless of the indicators used to compute the weight changes after delivery, attention is drawn to the approach for designating prepregnancy weight, the time frame of postpartum weight measurements and the use of overlapping variables, which results in bias (part–whole correlation). It is necessary to address criticisms on the accuracy of prenatal weight measurements and the way of expressing the maternal weight changes during and after pregnancy in order to have reliable results from research.
The present study assesses socio‐demographic and health service determinants of termination of breastfeeding within the first 2 years of life in India by analysing data from the nationally representative National Family Health Survey‐2 using Cox regression modelling techniques. While the likelihood of stopping breastfeeding increased with increasing household wealth status, it declined with increasing maternal age at childbirth. The likelihood of stopping breastfeeding was significantly higher among female children compared with male children, and the gender differential was attenuated by increasing maternal educational status. Overall, findings of the present study suggest that breastfeeding promotion programmes in India should focus on certain high‐risk mother–child pairs such as female infants, first‐born babies, babies born in the private sector and in urban areas, as well as mothers who are literate, have a higher wealth status, are aged less than 20 years and belong to Sikh or Christian communities. Qualitative studies to understand cultural factors or norms and causal pathways responsible for the association of identified factors and early termination of breastfeeding, especially household wealth status and maternal education, are also called for.
Fortified spread (FS), containing dry food particles embedded in edible fat, offers a convenient means for nutrition rehabilitation. To describe how caregivers feed FS to their undernourished children at home, and how FS use affects other feeding patterns, we conducted a longitudinal observational study in rural Malawi. Sixteen 6‐ to 17‐month‐old underweight children (weight‐for‐age z‐score < −2.0; −3.0 < weight‐for‐height z‐score < 0) received FS for 12 weeks. Twelve‐hour observations were conducted before supplementation and during weeks 1, 4, 8 and 12 of FS use. FS was fed to children about two times per day; each serving was 15–20 g. The spread was first used mainly alone as a between‐meal snack, and then became integrated into the typical complementary feeding pattern by being mixed with porridge. Introduction of FS reduced the number of plain porridge meals, but did not decrease the total number of meals or breastfeeds per day and did not change the daily mean time caregivers spent on feeding. Children accepted the FS well, but more FS was wasted when it was offered mixed with porridge than when given alone (23.6% vs. 1.2%, 95% CI for the difference 13.2% to 31.6%). FS supplementation is feasible for community‐based nutrition interventions in Malawi because it easily becomes part of the feeding routine, does not replace other foods and does not take extra caregiver time. To limit wastage, caregivers should be advised to serve FS plain or to mix it with only a small quantity of porridge.
None of the epidemiological studies indicating that obesity is a risk factor for asthma in schoolchildren have used the percent body fat (PBF) to define obesity. The present study compares the definition of obesity using body mass index (BMI), PBF and the raw sum of the thickness of four skinfolds (SFT) to evaluate this condition as a risk factor for asthma. All classes of children of the target ages of 6–8 years of all schools in four municipalities of Murcia (Spain) were surveyed. Participation rate was 70.2% and the number of children included in the study was 931. Height, weight and SFT (biceps, triceps, subscapular and suprailiac) were measured according to standard procedures. Current active asthma was defined from several questions of the International Study of Asthma and Allergies in Childhood questionnaire. Obesity was defined using two standard cut‐off points for BMI and PBF, and the 85th percentile for BMI, PBF and SFT. The highest quartile of each type of measurement was also compared with the lowest. A multiple logistic regression analysis was made for the various obesity definitions, adjusting for age, asthma in the mother and father and gender. The adjusted odds ratios of having asthma among obese children were different for boys and girls and varied across the different obesity definitions. For the standard cut‐off points of BMI they were 1.19 [95% confidence interval (CI) 0.41–3.43] for girls and 2.00 (95% CI 0.97–4.10) for boys; however, for PBF (boys 25%, girls 30%) the corresponding figures were 1.54 (95% CI 0.63–3.73) and 1.20 (95% CI 0.66–2.21). BMI, PBF and SFT showed more consistency between each other when using the other cut‐off points. BMI, PBF (except standard cut‐off points) and SFT produce relatively comparable results when analysing the interaction between obesity and asthma.