Effect of micronutrient supplement on health and nutritional status of schoolchildren: study design

Prevalence of vitamin A deficiency and dietary inadequacy in Indian school-age children and adolescents

PURPOSE

There are no representative estimates of vitamin A deficiency (VAD) and risk of vitamin A (VA) dietary inadequacy in Indian children and adolescents. To evaluate, from national surveys, the prevalence of VAD measured by serum retinol concentrations (< 0.7 µmol/L or < 20 µg/dL), and the risk of VA dietary inadequacy and excess intake beyond the tolerable upper limit (TUL).

METHODS

National and state-level VAD prevalence adjusted for inflammation was estimated in school-age children (5-9 years: 10,298) and adolescents (10-19 years: 9824) from the Comprehensive National Nutrition Survey (CNNS 2016-18). The risk of dietary inadequacy against age-specific average VA requirements, and excess intake against the TUL, was assessed from the National Sample Survey Office (NSSO 2014) data.

RESULTS

Serum retinol concentrations increased with age (5-19 years) in both genders and were significantly lower in school-age children (1.02 µmol/L, CI: 1.01-1.03) compared to adolescents (1.13 µmol/L, CI 1.12-1.15). The inflammation-adjusted prevalence of VAD in school-age children and adolescents was 19.3% (CI 18.8-19.9) and 14.4% (CI 13.9-14.9) respectively, and this was > 20% in seven and four states for children and adolescents, respectively. The prevalence of VAD was significantly higher among children with lower socio-economic status. The risk of dietary VA inadequacy, from the NSSO survey, was 69 and 78% in children and adolescents, respectively. This risk reduced to 6 and 17% with VA fortified oil and milk intake, while the proportion of intakes exceeding the TUL became 6 and 0.5% in children and adolescents, respectively.

CONCLUSIONS

The national prevalence of VAD in school-age children and adolescents in India was just less than 20%. The risk of dietary VA deficiency is likely to decline substantially with VA fortified food intake, but a risk of excessive intake also begins to appear; therefore, a careful assessment of the risk of hypervitaminosis A is required at these ages.

Occurrence of infections in schoolchildren subsequent to supplementation with vitamin D-calcium or zinc: a randomized, double-blind, placebo-controlled trial

BACKGROUND/OBJECTIVES

Vitamin D and zinc are recognized for their roles in immune-modulation, and their deficiencies are suggested to be important risk factors for childhood infections. This study, therefore, undertook to assess the occurrence of infections in rural Indian schoolchildren, subsequent to daily supplementation with vitamin D-calcium or zinc for 6 months.

MATERIALS/METHODS

This was a randomized, double-blind, placebo-controlled trial in apparently healthy 6–12 year-old rural Indian children, recruited to 3 study arms: vitamin D arm (1,000 IU D3 - 500 mg calcium, n = 135), zinc arm (10 mg, n = 150) and placebo arm (n = 150). The infection status was assessed using a validated questionnaire, and the biochemical parameters of serum 25(OH)D and serum zinc were measured by ELISA and colorimetry, respectively. The primary outcome variable was occurrence of infections (upper respiratory and total infections).

RESULTS

Serum 25(OH)D concentration in the vitamin D arm improved significantly by 34%, from 59.7 ± 10.9 nmol/L to 80 ± 23.3 nmol/L (P < 0.0001), but no improvement was observed for serum zinc concentration. While there was significant increase in the percentage of children reporting no or mild upper respiratory tract infections (URTI) and total infections (TI) in all three groups, improvements in the supplemented groups were similar to the placebo group. However, the vitamin D arm reported lower URTI and TI status in the vitamin D sufficient versus insufficient children. Also, URTI and TI status were found to be significantly (P < 0.0001) lower in children with improved 25(OH)D versus unchanged 25(OH)D.

CONCLUSIONS

Vitamin D-calcium supplementation helped to improve the vitamin D status but exerts no effect on the occurrence of infections when compared to the placebo group. Improvement in the serum 25(OH)D concentrations and attainment of vitamin D sufficiency may exert a beneficial effect on the infection status and needs to be investigated further. To evaluate the efficacy of zinc supplementation, higher dosages need to be administered in future studies.

The effects of regular consumption of a multiple micronutrient fortified milk beverage on the micronutrient status of school children and on their mental and physical performance

Multiple micronutrient deficiencies exist in school going children in India and bridging the gap between nutrient intake and requirements is an effective way to combat the deficiencies. This study aimed to test the effect of a multi-micronutrient fortified malt and cocoa based milk beverage on the micronutrient status, cognition, physical performance and nutritional deficiencies of 7-10 years old south Indian children. A randomized, double blind placebo controlled study design was used with normal healthy children from low to middle income families, aged 7-10 years randomly assigned to receive either a multi-micronutrient fortified or an unfortified milk based control drink. The drinks were provided 6 days/week for 5 months. Assessments included anthropometry, blood biochemistry, physical performance and cognition at baseline and endline. The baseline characteristics of the study groups were similar. The changes in body weight and height were similar between the groups at the end of the study. Levels of vitamin B12, red cell folate and vitamin B2 significantly improved in the intervention group, while vitamin D, selenium and body iron showed no difference. The Hemoglobin (Hb) and serum ferritin levels of the control group decreased at endline, while those in the intervention group maintained their levels. The serum transferrin receptor levels increased in both the groups. The prevalence of iron deficiency and Vitamin B2 deficiency were significantly lower in the intervention group at endline. Overall improvement in cognitive and physical performance was seen in both the groups at endline, with no significant differences between the groups. The micronutrient fortified milk based drink was efficacious in improving the micronutrient status of Vitamin B2, Vitamin B12 and red cell folate and in preventing a decline in Hb level compared to an unfortified milk based drink. It also reduced anemia and the risk of deficiencies of iron, and B12, in apparently healthy children. ClinicalTrials.gov IdentifierNCT01415557. Clinical Trial RegistryIndia - REF/2012/12/004332.

School-based calcium-vitamin D with micronutrient supplementation enhances bone mass in underprivileged Indian premenarchal girls

Low adult bone mass is linked to osteoporosis and fractures and is dependent on the extent of childhood and adolescent bone mineralization. The aim of the study was to investigate the effect of 1-year supplementation of calcium, multivitamin with zinc along with vitamin-D on bone mass accrual of school-going premenarchal girls from low income groups in Pune, India. Double-blind, matched-pair, cluster, randomization study was carried out in 214 premenarchal girls (8-12 years) from 2 schools in Pune, India. The two schools together formed 3 classes with 3 clusters each of age-matched girls of which one cluster was allocated to either one of the intervention groups (Ca-group:500 mg/d calcium, Ca+MZ-group:500 mg/d calcium+multivitamin tablet containing 15 mg/d zinc) or control group (C-group: multivitamin tablet without any minerals); all subjects received vitamin-D supplementation. Anthropometry, biochemical parameters, total body bone mineral content (TBBMC) and bone mineral density (TBBMD) (Dual energy X-ray absorptiometry) were assessed at baseline and endline. Post supplementation, mean percent increase in TBBMC was significantly higher in Ca-group (22.3%) and Ca+MZ-group (20.8%) compared to C-group (17.6%) (p<0.05) with no significant differences observed between Ca+MZ and Ca groups (p>0.1). Improvement in TBBMC-for-age Z-scores was higher in the two calcium supplemented groups (13.6%-22%) compared to the C-group (no improvement). Calcium supplementation, with or without multivitamins and zinc, showed a promising improvement in bone health especially with regards to improvement in bone related Z-scores in our population of underprivileged premenarchal girls.

Can multi-micronutrient food fortification improve the micronutrient status, growth, health, and cognition of schoolchildren? A systematic review

Micronutrient deficiencies compromise the health and development of many school-age children worldwide. Previous research suggests that micronutrient interventions might benefit the health and development of school-age children and that multiple micronutrients might be more effective than single micronutrients. Fortification of food is a practical way to provide extra micronutrients to children. Earlier reviews of (multiple) micronutrient interventions in school-age children did not distinguish between supplementation or fortification studies. The present review includes studies that tested the impact of multiple micronutrients provided via fortification on the micronutrient status, growth, health, and cognitive development of schoolchildren. Twelve eligible studies were identified. Eleven of them tested the effects of multiple micronutrients provided via fortified food compared to unfortified food. One study compared fortification with multiple micronutrients to fortification with iodine alone. Multi-micronutrient food fortification consistently improved micronutrient status and reduced anemia prevalence. Some studies reported positive effects on morbidity, growth, and cognitive outcomes, but the overall effects on these outcomes were equivocal.

Prevalence of vitamin D deficiency among Turkish, Moroccan, Indian and sub-Sahara African populations in Europe and their countries of origin: an overview

Vitamin D status of nonwestern immigrants in Europe was poor. Vitamin D status of nonwestern populations in their countries of origin varied, being either similar to the immigrant populations in Europe or higher than in European indigenous populations. Vitamin D concentrations in nonwestern immigrant populations should be improved.

PURPOSE

The higher the latitude, the less vitamin D is produced in the skin. Most European countries are located at higher latitudes than the countries of origin of their nonwestern immigrants. Our aim was to compare the serum 25-hydroxyvitamin D (25(OH)D) concentration of nonwestern immigrant populations with those of the population in their country of origin, and the indigenous population of the country they migrated to.

METHODS

We performed literature searches in the "PubMed" and "Embase" databases, restricted to 1990 and later. The search profile consisted of terms referring to vitamin D or vitamin D deficiency, prevalence or cross-sectional studies, and countries or ethnicity. Titles and abstracts were reviewed to identify studies on population-based mean serum 25(OH)D concentrations among Turkish, Moroccan, Indian, and sub-Sahara African populations in Europe, Turkey, Morocco, India, and sub-Sahara Africa.

RESULTS

The vitamin D status of immigrant populations in Europe was poor compared to the indigenous European populations. The vitamin D status of studied populations in Turkey and India varied and was either similar to the immigrant populations in Europe (low) or similar to or even higher than the indigenous European populations (high).

CONCLUSIONS

In addition to observed negative consequences of low serum 25(OH)D concentrations among nonwestern populations, this overview indicates that vitamin D status in nonwestern immigrant populations should be improved. The most efficacious strategy should be the subject of further study.

Imbalanced dietary profile, anthropometry, and lipids in urban Asian Indian adolescents and young adults

OBJECTIVE

To analyze the macronutrient, micronutrient, food intake pattern, anthropometry, and lipid profile of urban Asian Indian adolescents and young adults and compare it with the nutrient profile of rural Asian Indian and American adolescents.

METHODS

This was a cross-sectional, epidemiologic descriptive study. Body mass index (BMI), percentage body fat, waist and hip circumferences, skinfold thickness, serum lipids, and dietary intake were assessed in 1236 subjects (607 males, 629 females) aged 13-25 years from schools and colleges of a metropolitan city of India.

RESULTS

The mean age and BMI of study subjects were 17.6 +/- 2.4 years (range 13-25 years) and 19.8 +/- 3.3 kg/m(2) (range 11.9-35.9 kg/m(2)), respectively. The mean daily percentages of total energy contributed by carbohydrates, total fats, proteins, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), polyunsaturated fatty acids (PUFAs), omega-3 PUFAs, omega-6 PUFAs, and trans-fatty acids for all subjects were 53%, 34%, 11%, 11%, 10%, 9%, 1%, 8%, and 0.3%, respectively. The absolute daily intake of total fat was 84 +/- 29 g/d in males and 72 +/- 21 g/d in females, which was approximately 4 times the recommended dietary allowance for Asian Indians (20-22 g/d). Among food groups, a high intake of milk, milk products, roots, and tubers was observed. In these young individuals, the prevalence of hypercholesterolemia (males > or =169 mg/dl; females > or =181 mg/dl) and overweight (BMI > or =23.1 kg/m(2)) was 14.4% and approximately 16%, respectively. On comparison with rural Asian Indian adolescents, an inappropriately high intake of total fat was observed in our subjects. On the other hand, the percentage of energy intake of SFAs in Asian Indian and American adolescents was at par.

CONCLUSIONS

High total fat and SFA intake and a low intake of MUFAs and omega-3 PUFAs showed imbalanced nutrition, which could be responsible for the increasing prevalence of obesity and insulin resistance in urban Asian Indian adolescents and young adults. Nutritional strategies for reducing SFA intake and balancing the omega-3/omega-6 PUFAs ratio should be urgently applied in Asian Indian adolescents and are also presented in this paper.

Effect of micronutrient supplementation on health and nutritional status of schoolchildren: growth and morbidity

OBJECTIVE

We evaluated the effect of a micronutrient-fortified beverage on growth and morbidity in apparently healthy schoolchildren.

METHODS

This was a double-blind, placebo-controlled, matched-pair, cluster, randomized study in semi-urban middle-income residential schoolchildren aged 6 to 16 y. Anthropometrics (height and weight), clinical symptoms of deficiency, and morbidity data were collected at baseline in the supplemented group (n = 446 in 10 grades) and the placebo group (n = 423 in 10 grades) and after 14 mo of supplementation (n = 355 in the supplement group and n = 340 in the placebo group from nine pairs).

RESULTS

After 14 mo of supplementation, there was a significant increase in mean increments of height and weight z scores of -0.04 and 0.02, respectively, in the supplemented group compared with -0.14 and -0.09 in the placebo group. Velocity of weight (3.56 versus 3.00) was significantly (P < 0.01) higher with supplementation. Although there were no differences in the incidence of common childhood diseases such as fever, cough and cold, diarrhea, and ear infections elicited for a reference period of 1 mo at every quarterly follow-up examination, the mean duration of illness (calculated per person per year) was significantly shorter (5.0 d) in the supplemented group than in the placebo group (7.4 d).

CONCLUSIONS

The micronutrient-fortified beverage was beneficial in promoting growth and decreasing duration of common illnesses among middle-class residential schoolchildren who had adequate energy and protein intakes.

Effect of micronutrient supplement on health and nutritional status of schoolchildren: mental function

OBJECTIVE

We evaluated the effect of a micronutrient-fortified beverage on mental function in schoolchildren.

METHODS

This double-blind, placebo-controlled, matched-pair, cluster, randomized feeding trial assessed baseline before supplementation and after 14 mo in a cohort of 608 children aged 6 to 15 y who received a micronutrient-fortified beverage or placebo. Children in two classes (clusters) in each of nine grades were assessed for intelligence, attention and concentration, memory, and school achievement.

RESULTS

Mean intelligence quotient scores of the micronutrient-fortified beverage group and the placebo group at baseline and final follow-up were not significantly different. Mean verbal and performance scores and increments were also not different. After supplementation, attention-concentration increment scores of the micronutrient group were significantly higher (P < 0.05) than those of the placebo group. Mean and incremental scores of the supplemented group on the memory scale were not significantly different from those of the placebo group.

CONCLUSIONS

Supplementation with a beverage fortified with a range of micronutrients significantly improved attention-concentration over 14 mo, but not intelligence quotient, memory, or school achievement among middle-income schoolchildren.

Effect of micronutrient supplement on health and nutritional status of schoolchildren: bone health and body composition

OBJECTIVE

We investigated the effect of a micronutrient-enriched beverage on body composition, bone mineral content (BMC), bone area, and bone mineral density (BMD) at various sites in schoolchildren.

METHODS

A double-blind, placebo-controlled, matched-pair, cluster, randomization study was carried out in residential schoolchildren 6 to 16 y of age who lived near Hyderabad, India. Children (n = 268) were selected randomly from two classes of each grade (1 to 9) and were provided a micronutrient-enriched beverage (n = 146) or a placebo drink (n = 122). Bone parameters such as BMC, BMD, and bone area at various sites and the entire body were measured with dual-energy X-ray absorptiometry at the beginning and end of the study. Increments of outcome variables were subjected to paired t test with appropriate corrections to assess the effect of the supplement on bone health.

RESULTS

After 14 mo, increments for height, weight, fat-free mass, percentage of fat, whole-body BMC, whole-body bone area, and BMD at the neck of the femur were significantly greater (P < 0.05) in the supplemented group than in the placebo group.

CONCLUSIONS

The micronutrient-rich supplement increased tissue growth and skeletal shell in apparently normal children in the 14-mo period. It did not increase whole-body or site-specific BMD except at the neck of the femur. Amounts of calcium and other nutrients contained in the supplement were inadequate for tissue growth with density increases. This study raises important questions about the nutrient requirements of Indian children who consume a diet of cereals and pulses.