Nutrition in adolescence

Adolescence is a stage of physical, emotional and social changes, during which the transition from childhood to adulthood occurs. Although it is difficult to establish its exact beginning and end, it is considered that the initial stage, called puberty, begins around 9 years of age in girls and 11 years of age in boys and extends until approximately 19 years of age in both sexes.

The profound changes that occur during this stage condition the anarchic behavior that characterizes adolescent behavior, reflected in the breakdown of compliance with many life habits, such as sleeping, studying and eating habits, among others.

All the transformations inherent to the transition, and the high nutritional demands required by the rapid growth of the body during this stage, turn this period into a phase of great nutritional risk, which requires the careful attention of parents, guardians or teachers in charge of the comprehensive development of adolescents.

Elements that influence the nutritional demand during adolescence

• Rapid growth of the organism.

• Modification of body composition.

• Individual variations in the level of physical activity.

Peculiarities of the growth of the organism during adolescence that demand greater nutritional intake.

The second and last period of rapid growth of the organism occurs during adolescence. As a result of the maturational differences between the sexes, the growth spurt in the female sex begins around 9 years of age and around 11 years of age in the male sex.

An accelerated growth of the skeleton occurs, which is manifested by an increase in height in females of 8 centimeters on average and 10 centimeters in males. In both sexes, the definitive height is reached between 18 and 20 years of age. Bone mass continues to increase until the age of 25.

Parallel to longitudinal growth, there is an increase in body mass, which almost doubles during this period, constituting another important element for the increase in the nutritional needs of the adolescent.

There is also an increase in blood volume and internal organs. Nutritional and energy restrictions during this period of accelerated growth can have a negative impact on height, muscle and bone mass.

Changes in body composition during adolescence

Changes in body composition affect the proportion of fat and fat-free tissues, occurring differently in both sexes.

In the male sex there is a large increase in non-fat tissues (mainly skeleton and muscle). Between 10 and 20 years of age, males increase their fat-free mass by an average of about 35 kilograms.

In the female sex, there is a smaller increase in non-fat tissues (mainly skeleton and muscle). Between the ages of 9 and 20 years, girls increase their fat-free mass by only about 18 kilograms on average. However, in the female sex, the increase in fat deposits is greater than in the male sex.

This difference in fat-free mass volume between the sexes has an impact on nutritional requirements, since muscle mass is metabolically more active, so boys need more energy than girls for similar levels of physical activity.

Recommendations for the level of physical activity during adolescence

The increase in physical activity should be in correspondence with the sex and the time of pubertal growth spurt.l It is not recommended to spend more than two hours a day in sedentary entertainment, such as watching television, video games, internet or computer.

At least one hour a day of moderate to vigorous physical activity should be performed, and twice a week should include exercises such as:

• Aerobics or yoga aimed at facilitating stretching, and flexibility to promote bone health.

• Outdoor activities, walking, running, swimming, cycling.

• Practice of collective sports, volleyball, basketball, handball, etc.

• Performance of strength exercises.

Influence of psychological, sexual and social changes on eating habits during adolescence.

In most adolescents, the process of psychological maturation, together with the bodily changes typical of puberty, provoke a set of controversial behaviors, motivated by their need for autonomy and the non-acceptance of their own physical or spiritual image, which favor their insecurity and instability. These traits can be manifested in their eating behavior, through the following actions:

Suppressing some of the main recommended meals. The meal they miss the most is breakfast, causing energy deficits in the morning, which affects their learning and school performance.

Habitually consume fast food outside the home. They usually select foods with high energy value and low fiber, vitamins and minerals. Example: fried foods, refined carbohydrates and energy drinks.

Eating incomplete meals out of hours "snacking", which usually provide many calories and few nutrients, favoring the appearance of cavities and obesity. They increase their intake of less healthy beverages such as soft drinks, juices and juices, to the detriment of water and milk consumption.

In their eagerness to be accepted, they are capable of practicing special diets (hypocaloric, vegetarian, macrobiotic, etc.) without the proper medical recommendations, compromising their current and future health.

Some start drinking alcohol excessively, usually with friends and away from home, mainly on weekends, causing serious disorders to the digestive system and the nervous system. In addition, moderate intakes of alcoholic beverages also cause nutritional imbalances that affect the absorption of folates and favor the elimination of zinc, magnesium and calcium through urine.

Factors that increase the risks for nutritional disorders during adolescence

Pregnancy: constitutes a nutritional risk for the mother and the future baby. Although there are individual variations depending on age and particular nutritional status, pregnant adolescents need higher nutritional requirements to meet their own development and that of the fetus.

Very intense physical activities: adolescents who perform very intense physical activities require the consumpti