Normally, the energy requirements of teenagers tend to parallel their growth rate, and individuals assess their energy needs by means of their appetite with remarkable precision.
As a result, the majority of teens maintain energy balance, and a varied food intake provides sufficient nutrients to ensure optimal growth and development.
However, stress and emotional upsets can seriously affect the energy balance in adolescents, resulting in the consumption of too little or too much food.
Mild or severe infections, nervousness, menstrual, dental or skin problems (acne) can result in depression of appetite, and those adolescents on marginal diets are the most vulnerable.
Emotional stress is often associated with food faddism and slimming trends, both of which can lead to eating disorders such as anorexia nervosa.
Overweight and obesity
On the other hand, the prevalence of overweight and obesity in children and adolescents is now a major nutritional problem and the condition is likely to persist into adulthood.
Developing teenagers are particularly concerned about their body image and excessive weight can have profound effects on their emotional well being as well as on their physical health.
The cause of obesity is multifactorial and socio-economic, biochemical, genetic, and psychological factors all closely interact.
Too little exercise
Lack of activity plays an important role in the development, progression and perpetuation of obesity in adolescence.
Surveys of young people have found that the majority is largely inactive and health professionals and governments are now encouraging higher levels of physical activity among children and adolescents.
Physical inactivity does not only have a prime role in the development of overweight and obesity, but also on the development of chronic diseases such as heart disease, certain cancers, diabetes, hypertension, bowel problems and osteoporosis in later life.
In addition, physical activity is related to improvements in body flexibility, balance, agility and co-ordination and strengthening of bones.
The current recommendation is for teenagers to try to be physically active for at least 60 minutes daily.
Source: The European Food Information Council (www.eufic.org)