What is the current reality in Chile?
In recent decades, Chile has undergone a great demographic and epidemiological change, which has led to an aging population and profound changes in its nutritional profile. In terms of eating habits and physical activity (PA), families have replaced the consumption of home-cooked meals with fast foods and foods with high caloric concentration, saturated fats and sugars (especially soft drinks). This type of food is far from the recommended healthy diets (Ministerio de Salud de Chile (Minsal)), which include 5 daily portions of vegetables and fruits of different colors, legumes and fish at least twice a week.
According to the results of the National Food Consumption Survey, 95% of the Chilean population does not have a healthy diet. In addition, about 80% of the population does not have regular PA (higher proportion in women) and children only do the activity associated with physical education in school, which is far from the minimum time of 60 minutes daily of PA recommended by the World Health Organization (WHO) for children aged 5-17 years. With all this, we have a sedentary population, which has increased the prevalence of excess malnutrition (overweight and obesity) and chronic non-communicable diseases (NCDs). Currently, Chile is the 6th member country with the highest malnutrition due to excess in children under the age of 6 (34.4% men and 33.7% women).
Excessive malnutrition among children
From this age onwards, the prevalence of excessive malnutrition rises significantly, reaching 53.7 per cent in girls and 53 per cent in boys in the first year of primary school. This prevalence is relatively similar by gender and increases slightly in the southern part of the country. School obesity is associated with adult obesity. Children are 5 and 9 times respectively more likely to become obese adults than normal-weight children.
The main consequences of an excessively malnourished schoolchild are the presence of cardiovascular risk factors, glucose intolerance and insulin resistance. Obesity is also associated with hypo-activity, low physical condition, psychological problems including depressive symptomatology or anxiety. Previous studies have examined the relationship between childhood obesity and academic performance (math and language test scores).
For example, Datar et al (2004) in a representative sample of more than 11,000 U.S. children (ages 4-5) found that overweight children had lower scores on standardized math and language tests than normal-weight children. Similar results begin to appear in representative samples of Chilean schoolchildren studying the relationship between excess malnutrition, health habits and academic performance measured with standardized tests. However, fewer studies analyze the relationship between nutritional status and mental health in children. Today, according to the revised bibliography, we have no knowledge of any previous study in Chile in which these relationships are analyzed in students of 1st and 2nd year of basic education.
What was done?
Based on the above, together with a group of researchers, an article was published in the Chilean nutrition magazine in June of this year.
In that article, two studies were contributed. The first had the objective of analyzing and associating nutritional status, school performance and physical condition in children with normal weight and malnutrition due to excess in the first and second basic years, and the second had the objective of establishing the relationship of nutritional parameters with variables of school performance and physical condition and, in addition, to evaluate variables of mental health, dietary intake habits and physical activity.
Both studies were carried out in first and second year schoolchildren. The first was conducted in 218 schoolchildren (114 boys and 104 girls) and the second in 58 (37 boys and 21 girls). In both studies, anthropometric parameters were obtained (weight, height, BMI/age), physical condition (sitting up test, horizontal jump to feet together, 12-meter run) and academic performance (math and language grades). Additionally, in the first study the waist circumference was measured (PC) and in the second health habits (eating habits and level of physical activity) and anxious symptomatology (Spence child anxiety scale).
What results did we find?
We found that boys and girls presented high levels of overweight and obesity (59.2% presented excess malnutrition, of which 24.3% were overweight (23.7% boys and 25.0% girls) and 34.9% were obese (36.0% boys and 33.7% girls). In both studies, and for both sexes, the prevalence of obesity was higher than that of overweight, surpassing the national prevalence (28.3 per cent in men and 22.3 per cent in women).
In both studies, schoo lchildren with higher BMI/age levels were in worse physical condition (more marked in girls), devoted fewer weekly hours to systematic physical activity, and ate more unhealthy foods. Consistent with a great deal of previous national and international literature.
We found no differences in academic performance given by nutritional status or gender in both studies. Mathematics and language averages were high in all groups (close to 6.0 on a scale of 1.0 to 7.0) compared to national averages of public schools (5.6), so finding differences due to a ceiling effect was unlikely; furthermore, comorbidities were not controlled.
On the other hand, overweight/obesity girls had lower levels of anxiety than normal-weight girls, a fact that diverges with human studies that have found an association between obesity and unhealthy consumption patterns with high levels of anxiety. This may be because research that has detected higher levels of anxiety evaluated adolescent women on weight-loss treatment or adolescents diagnosed with generalized anxiety or major depression. In the same vein, anxiety generated in childhood obesity could be explained, in part by dissatisfaction with body image, a fact that increases at puberty and is not as marked at ages as early as those evaluated in our study.
To date, no national studies have been found to compare our results, being the first to study the relationship between anxiety levels and the nutritional status of such young schoolchildren.
Although these results reveal the current nutritional, physical, academic and mental condition of basic schoolchildren, more studies are needed to confirm the high degree of obesity and overweight detected. Waiting for future studies, the results obtained could shed light on the current nutritional status, health habits, physical, academic and mental condition of schoolgirls in the province of Biobío, Chile.
Organisation for Economic Co-operation and Development (OECD), Overweight and obesity among children, in Health at a Glance 2015: OECD Indicators, OECD Publishing, Paris. France.
Cigarroa I, Sarqui C, Palma D, Figueroa N, Castillo M, Zapata-Lamana R, Escorihuela R. Nutritional status, physical condition, school performance, anxiety level and health habits in primary school students in the province of Bio Bío (Chile): cross-sectional study. Chil Nutr Vol. 44, No. 3, June 2017.