Paula Andrea Martins

Stunted children gain less lean body mass and more fat mass than their non-stunted counterparts: a prospective study

The aim of the present study was to analyse the changes in body composition of stunted children during a follow-up period and to test the hypothesis of a tendency to accumulate body fat as a consequence of undernutrition early in life. We selected fifty boys and girls aged 11 to 15, who were residents of slums in Sao Paulo, Brazil. Twenty were stunted (S) and thirty had normal stature (NS). The childrens nutritional status and body composition were assessed through anthropometry and dual-energy X-ray absorptiometry, at the beginning of the present study and after 3 years, and changes in lean mass (LM and LM%) and fat mass (FM and FM%) were calculated. Stunted boys accumulated more body fat (FM%: S=1.62%, NS=-3.40%; P=0.003) and gained less lean mass (LM%: S=-1.46, NS=3.21%; P=0.004). Stunted girls gained less lean mass (S=7.87 kg, NS=11.96 kg; P=0.032) and had significantly higher values of FM% at follow-up when compared with their baseline values (P=0.008), whereas non-stunted girls had a non-significant difference in FM% over time (P=0.386). These findings are important to understand the factors involved in the increased prevalence of overweight and obesity among poor populations, which appear to be associated with hunger during infancy and/or childhood.

Long-Lasting Effects of Undernutrition

Undernutrition is one of the most important public health problems, affecting more than 900 million individuals around the World. It is responsible for the highest mortality rate in children and has long-lasting physiologic effects, including an increased susceptibility to fat accumulation mostly in the central region of the body, lower fat oxidation, lower resting and postprandial energy expenditure, insulin resistance in adulthood, hypertension, dyslipidaemia and a reduced capacity for manual work, among other impairments. Marked changes in the function of the autonomic nervous system have been described in undernourished experimental animals. Some of these effects seem to be epigenetic, passing on to the next generation. Undernutrition in children has been linked to poor mental development and school achievement as well as behavioural abnormalities. However, there is still a debate in the literature regarding whether some of these effects are permanent or reversible. Stunted children who had experienced catch-up growth had verbal vocabulary and quantitative test scores that did not differ from children who were not stunted. Children treated before 6 years of age in day-hospitals and who recovered in weight and height have normal body compositions, bone mineral densities and insulin production and sensitivity.

Evidence for impaired insulin production and higher sensitivity in stunted children living in slums

The objective of the present study was to investigate the changes in glucose and insulin metabolism in nutritionally stunted children that can be involved in the appearance of chronic diseases in adulthood. For this purpose, sixty-one children were selected, thirty-five boys and twenty-six girls, residents of slums in São Paulo, Brazil. The children were classified according to the height-for-age as stunted (<or=-1.5 Z-score; n 21) or non-stunted (>-1.5 Z-score; n 40). The glucose and insulin plasma levels were determined and, from these values, the indexes that evaluate the pancreatic beta-cell function (homeostasis model assessment (HOMA-B)) and insulin sensitivity (HOMA-S) were assessed. Stunted children showed lower values of fasting insulin than those of the non-stunted group (boys: 29.7 (SD 14.9) v. 50.4 (SD 29.2) pmol/l, P=0.019; girls: 34.4 (SD 12.6) v. 62.3 (SD 28.7) pmol/l, P=0.016) but the glucose levels were similar (boys: 4.6 (SD 0.3) v. 4.5 (SD 0.3) mmol/l; girls: 4.2 (SD 0.3) v. 4.4 (SD 0.3) mmol/l). Stunted children showed lower HOMA-B values (boys: 83 (SD 22) % v. 115 (SD 36) %, P=0.011; girls: 107 (SD 23) % v. 144 (SD 46) %, P=0.045) and higher HOMA-S values (boys: 196 (SD 92) % v. 120 (SD 62) %, P=0.014; girls: 159 (SD 67) % v. 98 (SD 57) %, P=0.016). The results show a decreased activity of beta-cell function and increased insulin sensitivity in stunted children. The decreased beta-cell function of this group may strongly predict type 2 diabetes.

Availability of processed foods in the perimeter of public schools in urban areas

OBJECTIVES To assess the availability of food in relation to their degree of industrial processing and the types of food stores in the perimeters of elementary schools. METHODS This is a cross-sectional study. 82 food stores located within a 500 m radius buffer of three public schools located in three distinct regions with different socioeconomic levels in the municipality of Santos, state of São Paulo, Brazil, were assessed. All streets within a 500-meter radius of the schools were covered, geographic coordinates were recorded and information about the stores and food items available were collected by direct observation and interview with store managers. Available food items were classified in relation to their degree of industrial processing as ultra-processed foods and minimally processed foods. Kernels density maps were used to assess the degree of agglomeration of stores near the schools. RESULTS The stores that offered mostly ultra-processed foods were significantly closer to schools than those who offered mostly minimally processed foods. There was a significant difference between the availability of processed food in different types of stores and between the three regions assessed. CONCLUSIONS The data found by this work evidence that children who attend the three public schools assessed are exposed to an environment that encourages the consumption of ultra-processed foods through easier access of these products in the studied stores.

Comparison of techniques to evaluate adiposity in stunted and nonstunted children.

OBJECTIVE. The use of anthropometric measures (eg, skinfold thicknesses, BMI) to assess obesity is not without controversy and has not been explored with respect to the use among groups of children with growth retardation (ie, stunting). Therefore, the objective of this study was to determine whether growth retardation affects the accuracy of field methods for assessing body composition in children. METHODS. A cross-sectional study was conducted in 30 stunted children and 30 nonstunted children who were matched for age- and weight-for-height z score and living in the shantytowns of São Paulo, Brazil. Body composition (fat mass, fat-free mass, and percentage of body fat [%BF]) was measured by H218O dilution (reference technique) using group-specific values for the hydration of fat-free mass and dual-energy x-ray absorptiometry. BMI and body composition that were calculated from 3 pediatric skinfold prediction equations were evaluated for accuracy of %BF in comparison with the reference technique. RESULTS. Stunted children were shorter and weighed less than nonstunted children, but BMI did not differ significantly between groups. All 3 skinfold equations tested resulted in a calculated %BF that was significantly lower than that measured by H218O dilution for both stunted and nonstunted groups, and %BF as calculated by any of the skinfold equations tested did not significantly predict %BF by H218O dilution. In contrast, BMI significantly predicted %BF in both stunted and nonstunted children, and this relationship did not differ by growth status. CONCLUSION. BMI but not skinfolds significantly predicted %BF measured by H218O dilution. The relationship between BMI and %BF did not differ between stunted and nonstunted children; this indicates that BMI can be used in field studies of obesity and stunting. However, the prediction of %BF by BMI is relatively poor in both groups of children, and continued investigation of more accurate field methods for measuring %BF is warranted.

Changing the Food Environment for Obesity Prevention: Key Gaps and Future Directions

The food environment has a great impact on the nutritional health of the population. Food environment interventions have become a popular strategy to address the obesity epidemic. However, there are still significant gaps in our understanding of the most effective strategies to modify the food environment to improve health. In this review, we examine key gaps in the food environment intervention literature, including the need for: developing appropriate formative research plans when addressing the food environment; methods for selecting intervention domains and components; incorporating food producers and distributors in intervention strategies; strengthening evaluation of environmental interventions; building the evidence base for food environment interventions in diverse settings; engaging policy makers in the process of modifying the food environment; and creating systems science models to examine the costs and benefits of a potential program or policy on the food environment prior to implementation. In addition, we outline the need for strategies for addressing these issues including conducting pilot interventions, developing additional methodologies, and embracing the use of simulation models.

Validation of an Adapted Version of the Nutrition Environment Measurement Tool for Stores (NEMS-S) in an Urban Area of Brazil

OBJECTIVE To validate an adapted instrument that assesses the nutritional environment of food stores in Brazilian urban areas. METHODS The instrument measured aspects of food environment such as availability, prices, and quality. The Harvard Healthy Eating Pyramid and the degree of processing were used to define healthy foods. The sample included 44 food stores in 3 census tracts in the city of Santos. Inter-rater reliability and stability coefficient were obtained with measurements performed by different individuals at different times. Internal consistency and construct validity were assessed by Cronbach α and the known-groups comparison method, respectively. RESULTS Inter-rater reliability was high. The mean intra-class correlation coefficient was 0.98 and the mean kappa was 0.77. Cronbach α values ranged from .68 to .93. CONCLUSIONS AND IMPLICATIONS The instrument can be useful in the development of interventions to promote healthy eating through actions focused on healthy food availability in Brazilian communities.

Factors associated with overweight in children living in the neighbourhoods of an urban area of Brazil

OBJECTIVE The present study aimed to investigate the individual and family determinants of being overweight among children younger than 10 years of age. DESIGN Cross-sectional survey. Direct data on childrens age, food intake, physical activity, type of transportation used and anthropometric measurements, as well as the education level of the mothers, were collected by trained interviewers. SETTING Population-based study in the city of Santos, Brazil. SUBJECTS A total of 531 children under 10 years of age (302 aged <6 years, 229 aged ≥6 years), living in the city of Santos. RESULTS The overall prevalence of overweight and obesity (BMI-for-age Z-score >1) was 35·4 % for children under 6 years and 38·9 % for children aged 6-10 years. The socio-economic status of the family was associated with being overweight for both age groups. Logistic regression analysis showed that the lower the socio-economic status, the higher the likelihood of being overweight, among both younger children (OR = 7·73; P = 0·02) and older children (OR = 1·98; P = 0·04). The use of active transportation was associated with a lower likelihood of being overweight, but only among younger children (OR = 1·70; P = 0·05). CONCLUSIONS Socio-economic status seems to be an important individual-level determinant of overweight in children. Public policies should consider promoting the use of active transportation, as the results showed it to have a positive effect on reducing overweight issues. The high prevalence of overweight in younger children suggests that this age group should be a priority in health-promoting interventions.

Children recovered from malnutrition exhibit normal insulin production and sensitivity.

Protein-energy malnutrition promotes adaptive hormonal changes that result in stunting. A previous study showed that stunted children had increased insulin sensitivity and diminished pancreatic beta-cell function. The objectives of the present study were to analyse the glucose, insulin, homeostasis model assessment of insulin sensitivity (HOMA-S) and homeostasis model assessment of pancreatic beta-cell function (HOMA-B) levels after nutritional recovery. The recovered group (n 62) consisted of malnourished children after treatment at a nutrition rehabilitation centre. At the beginning of treatment their age was 2.41 (sd 1.28) and 2.31 (sd 1.08) years, weight-for-age Z score - 2.09 (sd 0.94) and - 2.05 (sd 0.55) and height-for-age Z score - 1.85 (sd 1.11) and - 1.56 (sd 0.90), for boys and girls respectively. The control group consisted of well-nourished children without treatment (n 26). After treatment, boys of the recovered group gained 1.29 (sd 1.06) Z scores of height-for-age and 1.14 (sd 0.99) Z scores of weight-for-age, and girls, 1.12 (sd 0.91) and 1.21 (sd 0.74) Z scores respectively. No differences were found between control and recovered groups in insulin levels for boys (P = 0.704) and girls (P = 0.408), HOMA-B for boys (P = 0.451) and girls (P = 0.330), and HOMA-S (P = 0.765) for boys and girls (P = 0.456) respectively. The present study shows that the changes observed previously in glucose metabolism and insulin were reverted in children who received adequate treatment at nutritional rehabilitation centres and showed linear catch-up.

Estado nutricional de crianças atendidas na rede pública de saúde do município de Santos

OBJECTIVE: Evaluate the nutritional status of children with 6 to 24 months of age assisted by the public health service in the city of Santos, Brazil, and its relation with socioeconomic status, health and nutritional conditions. METHODS: This cross-sectional study enrolled 95 children who attended regular pediatric visits in 5 units of public primary health centers. Weight and height were measured and parents were requested to answer a questionnaire with health, nutrition and socioeconomic information of their children. Nutritional status was assessed by the NCHS (1977), CDC (2000) and WHO (2006) child growth standard curves. Weight for age, height for age and weight for height Z scores were calculated. Values of the these indices below -2.0 Z score defined malnutrition and values of weight for height above +2.0 Z score defined overweight. RESULTS: The frequency of malnutrition according to the different indices were: weight for age 4.2%, 9.5% and 3.2%; height for age 2.1%, 2.1% and 4.2%, and weight for age 2.1%, 4.2% and 1.0%, respectively, according to the NCHS (1977), CDC (2000) and WHO (2006) reference curves. Overweight was found in 4.2%, 3.2% and 5.3% by the NCHS (1977), CDC (2000) and WHO (2006) reference curves, respectively. CONCLUSIONS: There was a low frequency of malnutrition. The WHO curve detected less patients with nutritional deficits than the other NCHS (1977) and CDC (2000) curves.