In children and adolescents, obesity is defined as excess weight 20% greater than the ideal weight calculated based on age, sex, and height. In most cases, obesity depends not only on genetic predisposition but also on excessive consumption of food (in particular, sugary drinks and high-calorie snacks), psychological, socioeconomic, and family factors, and insufficient activity.
The study of the genetic factors of obesity was mainly conducted on animal models. The genetic determinant of obesity is proven by the correlation of overweight in monovular twins in humans. Specifically, more than between fathers and children, the coincidence of obesity is particularly frequent between mothers and children. The fact that the weight of adoptive children correlates significantly with that of natural parents and not with that of adoptive parents demonstrates the fundamental role of the genetic transmission of obesity for environmental conditioning irrefutably.
The possible contribution of a thermogenic defect in the etiology of obesity is controversial: in the obese, a decrease in the thermal response to food has been described, which depends 75% on the energy cost of digestion, absorption, and metabolism. And food storage is believed to be due to more energy-efficient metabolic pathways. For example, the more excellent the thermal response to carbohydrates, the higher the glucose utilization rate: small decreases in the thermal response can result from insulin resistance and lower glucose availability in the obese.
Minor differences in calorie utilization maintained for years can significantly contribute to the net calorie balance. Numerous studies have shown that Basal Metabolism (energy consumption at rest) depends on the lean mass. Given that obese individuals have a higher value of lean mass than lean control subjects, the Basal Metabolism of obese subjects is higher. However, when Basal Metabolism is affected by the effect of fat mass, it is similar in obese and non-obese.
It seems likely that psychological factors also contribute to the formation of exogenous obesity, which represents the majority of cases. The nursing mother offers her baby not only milk but also support, warmth, smell, care, and eye contact, thus satisfying her primal needs di lei. In this way, food becomes a way of giving and taking for the mother and the child and a vehicle for messages of love or aggression. This is why food is loaded with complex values and symbols (social, ethnic, ethical, religious …) in every country and culture.
The importance of the family in the onset of obesity can therefore be explained above all, but not exclusively, as a food habit transmitted by a cultural and emotional attitude of the parents. Many obese kids have an altered family situation. In particular, the mother plays a dominant role in the family, exercising natural control over the child, hindering the development of autonomy, and often stimulating him to feed excessively. For these mothers, nutrition would acquire an emotional value by configuring itself as a means to express one’s affection, to cultivate feelings of guilt towards children towards whom they would feel inadequate.
On the other hand, the child, who has unmet emotional needs due to maternal deficiencies, would react with a growing demand for food which represents compensation and comfort for him; therefore, his resistance of him to adhering to food control maybe because for him this means a severe loss of compensatory substitutes and anxiety regulators. Although the influence of the mother’s caloric intake is more present than that of the father, the habits of both parents nevertheless play an essential role in the way children eat at preschool age.
In addition to practical deficiencies, other factors can favor the onset and persistence of obesity by profoundly altering the emotional balance, such as emotional trauma and social maladjustment. Among these, the following can be considered necessary in the pathogenesis of obesity :
Predominantly Sedentary Extra-Curricular Activities
Recent epidemiological studies have shown that 3/4 of children spend more than two hours a day in front of the TV, while only 50% of adolescents practice sports regularly.
Low Socioeconomic Level
This parameter is also relevant in the pathogenesis of obesity. The caloric intake is higher in the low socioeconomic groups of the population than in the upper social classes; moreover, the prevalence of excess weight is significantly higher in this common standard of living styles.
Incorrect Eating Behavior
The analysis of eating behavior is vital because habits formed early in life in response to physiological demands and psycho-social pressures can considerably impact long-term health. the most common errors encountered in young people are:
- little or no breakfast ;
- absent snacks or based on foods with reduced nutritional value;
- little or no consumption of vegetables and fruit ;
- excessive consumption of cold cuts, chocolate, bars, French fries, candies, and other packaged sweets, carbonated and sugary drinks;
- excessive space for fast food, rich in foods with a high content of calories, saturated fats, salt, and simple sugars, and poor fiber and vitamins.
Metabolic Syndrome In The Child
The treatment of obesity, essential in developmental age, must have a positive and persistent impact on the child’s diet, behavior, and physical activity: therapeutic programs cannot ignore the provision of intervention at each of the three levels. As for the dietary therapy of obesity, its aims can be summarized in the following points:
- reduction of overweight and achievement of a new balance between energy expenditure and caloric intake (through the enhancement of physical activity and persistent modification of lifestyle and nutritional habits );
- maintenance of lean mass and, therefore, in particular of muscle mass which represents the metabolically active body compartment, capable of positively affecting the basal metabolism and, consequently, the total energy expenditure;
- reduction of fat mass ;
- maintenance of adequate growth rates;
- achievement of a correct weight ratio and stature ;
- correct nutrition with an adequate distribution of nutrients and choice of foods capable of inducing a high sense of satiety;
- maintenance of the achieved body-weight balance;
- prevention of complications of obesity.
The diet must be accompanied by an adequate intervention from both an anthropometric and psychological point of view: to obtain a correct and lasting relationship between weight and height. The therapeutic program must be able to radically modify the nutritional and life habits of the child and his family with real educational action. The involvement and collaboration of the whole family are fundamental prerequisites for the success of the therapy set and the child’s compliance with the established scheme. Moreover, a qualified, demanding and constant intervention is required. Clinical monitoring over time is essential to assess the chosen therapeutic approach’s adequacy and guide any changes. On the part of the therapist, to choose the most appropriate dietary approach, it is essential to evaluate:
- age of the child with relative caloric and nutritional needs
- extent of overweight
- any complications related to obesity already present or at an increased risk of occurrence due to positive familiarity
- cardiovascular risk, through a careful family history
- any presence and severity of the eating disorder ( DCA)
- nutritional habits
- lifestyle habits (active or passive)
- complete physical examination
In principle, you can choose whether to educate the child to correct eating behavior through a balanced norm caloric diet or to propose a low-calorie diet plan. In this case, no more than 250 kcal per day is reduced from the caloric requirement to obtain a monthly weight loss of no more than 5-6% if the child is less than 12 years old and 7-8% if he is older. In the face of the difficulty and limitations of diet in the obese young, it may be sufficient to keep the weight stable, as growth in height may be enough to decrease the BMI automatically. The following tables show the reference values for age and sex in the population of young people of average build, the ideal body weight, and the energy needs to be met based on the degree of physical activity performed.