Seasonal variation in food pattern but not in energy and nutrient intakes of rural Beninese school-aged children.

BACKGROUND: Inadequate energy and nutrient intakes are a major nutritional problem in developing countries. A recent study in Beninese school-aged children in different seasons revealed a high prevalence of stunting and poor iron status that might be related to the food pattern. OBJECTIVE: To analyse the food pattern and resulting energy and nutrient intakes of rural Beninese school-aged children in relation to season and school attendance. SUBJECTS AND METHODS: The study was performed in northern Benin in eighty randomly selected children aged 6-8 years. Dietary intake was assessed using observed weighed records. Food, energy and nutrient intakes were measured in post- and pre-harvest seasons. Complete food consumption data sets were available for seventy-five children. RESULTS: Food pattern showed seasonal variations. Cereals, roots and tubers were the main staple foods. Contributions of animal products to the diet were very small. The food pattern was not different for either boys v. girls or for children attending v. not attending school. Median daily energy intakes were 5.0 and 5.3 MJ in the post- and pre-harvest season, respectively. Only fat and vitamin C showed seasonal differences (P < 0.05). Energy and nutrient intakes were different for boys and girls but, unexpectedly, not for children attending v. not attending school. CONCLUSIONS: Seasonal variations in food pattern did not result in seasonality in energy and nutrient intakes. Because the children's diet was low in animal products, protein, fat and vitamin C and high in fibre, the absorption of fat, fat-soluble vitamins, carotenoids, Fe and Zn might be low. Fe and Zn bioavailability from such a diet needs further investigation.

Effects of multivitamin-multimineral supplementation on appetite of stunted young Beninese children.

In the developing world, food intake of young children is often insufficient for growth. Reduced appetite due to several factors including micronutrient deficiencies might be an explanation. We hypothesized that a multivitamin-multimineral supplementation will improve appetite of stunted children in south of Benin. Multivitamin-multimineral supplements (VITALIA-tablets) contain 11 vitamins and 8 minerals. Stunted children (Ht/Age Z score < -2) of 17-32 months old were randomly assigned to multivitamin-multimineral (n = 48) or placebo (n = 53) group. Supplementation was daily and supervised throughout 6 weeks. Knee-heel length, length, weight, arm circumference and appetite were assessed once a week for the three weeks preceding and the three weeks following the six-week intervention period. Growth was additionally assessed 4 months after intervention. Each appetite test day, morbidity data and mother's report on child's appetite throughout the preceding day were recorded. Reported appetite, intake of test food and knee-heel length increased after supplementation in both groups (p < 0.05), but were not different between groups. Growth was similar 4 months after the intervention. Morbidity was comparable in both groups before as well as after supplementation. We conclude that 6-week multivitamin-multimineral supplementation alone failed to improve appetite and growth of stunted young children.

An appropriate tool for appetite testing and evaluation in young children in Benin.

Appetite measurements were performed in 109 Beninese children aged 18-30 months to develop a tool for appetite evaluation in young children in nutritional intervention programmes. Two test foods were identified as appropriate for these children: a maize porridge (aklui) and rice (riz-au-gras). Ad libitum intakes of the foods served after an overnight fast according to a standardized offering procedure were measured on 3 days. The children's habitual intakes were measured during 3 consecutive days not overlapping with the days when the test meals were provided. Energy intake from the test foods was comparable to breakfast energy intake which was 0.8-1.0 MJ, representing 21% of total daily energy intake. Energy intake from aklui was significantly correlated with daily intake (r=0.41, n=38, p<0.05) and with energy intake from breakfast (r=0.52, p<0.01). Correlations concerning riz-au-gras were less pronounced and non-significant. Reproducibility (as coefficient of variation) of the appetite test as calculated from the triplicate measurements was 40% for aklui and 25% for riz-au-gras. This reproducibility is better than that of the habitual breakfast intake (43-45%). In conclusion, the appetite test used in our studies can be considered as an appropriate tool in appetite evaluations.

Multivitamin-multimineral and iron supplementation did not improve appetite of young stunted and anemic Beninese children.

In developing countries, low food intake is often reported in children < 5 y old. Reduced appetite may be a contributing factor. We investigated whether a combination of a multivitamin-multimineral supplement and additional iron treatment improved appetite and growth of 18- to 30-mo-old stunted and anemic Beninese children. The study was placebo-controlled using VITALIA tablets (11 vitamins and 10 minerals) and ferrous fumarate tablets (66 mg of iron). One hundred fifty stunted (height-for-age Z score < -2) and anemic children (hemoglobin < 110 g/L) were randomly assigned to one of four groups: group 1, multivitamin-multimineral plus iron; group 2, multivitamin-multimineral plus placebo; group 3, placebo plus placebo; and group 4, placebo plus iron. Supplementation was daily and supervised for 6 wk. Appetite, knee-heel length, dietary intakes and morbidity were assessed before and after supplementation. Length, weight, arm circumference and hemoglobin concentration were assessed before, just after supplementation and 4 mo after the intervention. Appetite was assessed by means of an appetite test using a test food, riz-au-gras, eaten ad libitum after an overnight fast. Dietary intakes were assessed during three consecutive days in a subsample by means of the observed weighed record method. Energy intake from the habitual breakfast was significantly correlated with that from the test food (r = 0.49, n = 38, P = 0.002). There were no differences among groups in changes in appetite and growth performance. The habitual diet of the children was monotonous and contained only small amounts of animal products. The morbidity status of the children was comparable in all study groups, before as well as after supplementation. We conclude that the 6-wk multivitamin-multimineral supplementation with additional iron treatment failed to improve the appetite and growth of the children.

Serum thyroglobulin and urinary iodine concentration are the most appropriate indicators of iodine status and thyroid function under conditions of increasing iodine supply in schoolchildren in Benin.

Iodine deficiency control programs have greatly reduced iodine deficiency disorders worldwide. For monitoring changes in iodine status, different indicators may be used. The aim of this study was to evaluate the suitability of indicators of iodine status and thyroid function, thyroglobulin (Tg), thyroid-stimulating hormone (TSH) and free thyroxine (FT4) in serum, thyroid volume and urinary iodine concentration, in iodine-deficient schoolchildren under conditions of increasing iodine supply. The study was established as a double-blind, placebo-controlled oral administration of a single dose of iodized oil to schoolchildren (7-10 y old), living in an iodine-deficient area of Benin, with an observation period of 10 mo. However, 3-4 mo after supplementation, iodized salt became available in the area. The study population therefore comprised an iodized oil-supplemented group and a nonsupplemented group, both of which had variable, uncontrolled intakes of iodized salt during the last 6 mo of the study. Initial mean serum concentrations of TSH and FT4 were within the normal range, whereas serum Tg concentration, urinary iodine concentration and thyroid volume were indicative of moderate-to-severe iodine deficiency. At the end of the study, all indicators had improved significantly, except thyroid volume, which had decreased only in the supplemented group. The supplemented group also still had significantly lower serum Tg and higher urinary iodine concentrations than the nonsupplemented group. Serum Tg and urinary iodine concentrations are the indicators most influenced by a changing iodine supply. Current normal reference ranges of serum concentrations of TSH and FT4 are too wide for detecting iodine deficiency in this age group.

Mild iodine deficiency is associated with elevated hearing thresholds in children in Benin.

OBJECTIVE: Elevated hearing thresholds have been demonstrated in populations afflicted by endemic cretinism as a result of severe iodine deficiency. However, data on the effects of less severe iodine deficiency on hearing thresholds in apparently normal children are scant. This study addresses the question whether there is a relationship among iodine variables, hearing and mental performance in a mildly iodine-deficient population. DESIGN: A randomized, placebo-controlled intervention trial with an observation period of 11 months. SETTING: An iodine-deficient area in northern Benin. SUBJECTS: A total of 197 school children, aged 7-11 y. INTERVENTIONS: A total of 97 children received an oral dose of iodized oil, containing 540 mg I, while 100 children received a placebo. About 3-4 months after supplementation, the whole population began to have access to iodized salt. Non-verbal mental tests were administered and biochemical indicators (thyrotropin, free thyroxine, thyroglobulin and urinary iodine) were measured at the beginning and the end of the study. Hearing was measured at the end of the study in both ears by pure-tone audiometry at seven frequencies. RESULTS: In this mildly iodine-deficient child population children with higher serum thyroglobulin concentrations had significantly higher hearing thresholds in the higher frequency range (> or = 2000 Hz) than children with lower serum thyroglobulin concentration. Moreover children with lower hearing thresholds performed significantly better on the mental tests used. CONCLUSIONS: Even when iodine deficiency is 'mild', promotion of adequate iodine intake through salt iodization programs and other means remains crucial. SPONSORSHIP: Nestlé Foundation, Lausanne, Switzerland; Wageningen University, Wageningen, The Netherlands.

Impact of iron supplementation and deworming on growth performance in preschool Beninese children.

OBJECTIVE: To assess the effects of iron and deworming on linear growth performance of preschoolers. DESIGN: Three-month randomized, double-blind and placebo-controlled trial. The children were allocated to four treatments: iron (60 mg elemental iron/day) + albendazole (200 mg/day for 3 consecutive days, repeated 1 month later), iron + albendazole-placebo, albendazole + iron-placebo or placebos. The supplementation was supervised. SUBJECTS: A group of 177 children aged 3-5 y was selected from low-income households in a rural area in southern Bénin. A complete data set was analysed for 140 subjects. Many children were stunted (58% had height-for-age Z-score <-2), none were wasted (2% had weight-for-height Z-score < -2) and 76% were anemic (Hb < 110 g/l). MAIN OUTCOME MEASURES: Anthropometric parameters, hemoglobin and eggs per gram feces. RESULTS: No significant difference in changes in anthropometric parameters was observed between study groups, and also not in a sub-sample of stunted and anemic subjects. Changes in hemoglobin were highest in the iron-treated subjects at the end of the 3-month intervention period (P = 0.032). The difference between the iron and the placebo groups remained significant even 7 months later (P = 0.022). The difference was 5 g/l in both periods. Ascaris lumbricoides and hookworm infections decreased significantly in albendazole-treated subjects (P < 0.05). CONCLUSIONS: In addition to recurrent parasitic infection burden, the children may have multiple micronutrient deficiencies. Therefore, it may be interesting to study appetite and food intake of young toddlers in relation to health and linear growth performance in poor environments.

Improved iodine status is associated with improved mental performance of schoolchildren in Benin.

BACKGROUND: An adequate iodine supply in utero and shortly after birth is known to be crucial to an individual's physical and mental development. The question of whether iodine supplementation later in life can exert a favorable influence on the mental performance of iodine-deficient populations was addressed in various studies, but with contradictory results. OBJECTIVE: The aim of this study was to examine the effect of an improvement in iodine status on mental and psychomotor performance of schoolchildren (7-11 y) who were moderately to severely iodine deficient. DESIGN: The study, which was originally planned as a double-blind, randomized, placebo-controlled intervention, was carried out in an iodine-deficient population of schoolchildren (n = 196) in northern Benin. As the population began to have access to iodized salt during the 1-y intervention period, the study population was split post hoc-on the basis of urinary iodine concentrations-into a group with improved iodine status and a group with unchanged iodine status. Changes in mental and psychomotor performance over the intervention period were compared. RESULTS: Children with increased urinary iodine concentrations had a significantly greater increase in performance on the combination of mental tests than did the group with no change in urinary iodine concentrations. CONCLUSIONS: An improvement in iodine status, rather than iodine status itself, determined mental performance in this population, which was initially iodine deficient. These findings suggest a "catch-up" effect in terms of mental performance.

Resting metabolic rate and work efficiency of rural Beninese women: a 2-y longitudinal study.

This study was performed on 34 female farmers in northern Benin during 2 consecutive years. Body composition, energy intake, energy expenditure, resting metabolic rate (RMR), and energy cost of cycling on a bicycle were measured in three periods per year. Energy intake showed seasonal fluctuations of approximately 1.7 MJ/d in 1990 and 0.6 MJ/d in 1991. Body weight fluctuated between periods, with the lowest weight in preharvest periods. Observed changes in body weight were 2.6 +/- 2.3 and 0.9 +/- 1.7 kg in 1990 and 1991, respectively. The same pattern was observed in both fat mass and fat-free mass. RMR, energy cost of cycling, and delta work efficiency did not show any seasonal changes. It is concluded that metabolic adaptation, as a response to a seasonal food shortage up to 15% of average daily intake, will not occur.

The significance of socio-economic characteristics for adult seasonal body-weight fluctuations: a study in north-western Benin.

Large variations in seasonal body-weight fluctuations have been described for individuals from different households living and working under comparable circumstances. In the present study the relationship between socio-economic household characteristics and seasonal body-weight fluctuations of individual members of rural Beninese households were studied. No significant correlation was found for body-weight fluctuation between the two study years, nor for body-weight fluctuation of men and women belonging to the same household. When comparing dichotomized socio-economic classes for relative body-weight fluctuation of men and women in both study years, no consistent trends were observed for both years nor for both sexes. The distribution of subjects with a consistent high weight fluctuation over the two study years did not differ between socio-economic groups. In conclusion it may be stated that there were no indications that socio-economic characteristics play a determining role in the magnitude of body-weight fluctuation of this study population, despite the large variations observed in the latter. Therefore it is most likely that other factors decide the weight fluctuations of individuals, health and sanitation being the most likely candidates.