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Adolescence is a period of physical, social and psychological transition between childhood and adulthood. Its length varies, in different cultures and different individuals, on average lasting from 10 to 19 years of age. Adolescence is characterized by major growth and by many physiological changes associated with the increased production of sex hormones (puberty). It can involve a number of physical ailments (acne, scoliosis) and behavioral problems: mood swings, depression, drug addiction, eating disorders. Adolescence is also a period during which sexuality is a major preoccupation: first romance, first sexual relations, identification of sexual orientation, etc.


Puberty is the time of life when children reach sexual maturity. They then become capable of reproduction. The age at which puberty occurs varies, depending on several different factors, particularly genetic factors, although it usually comes earlier in girls than in boys. It begins when the pituitary gland starts to produce gonadotropins, hormones that stimulate the growth of the gonads (ovaries or testicles) and the secretion of the sex hormones (testosterone or estrogen). The sex hormones trigger the development of the genital organs and the gradual appearance of the secondary sex characteristics, which are morphological and behavioral characteristics that differentiate the two genders but that are not a part of the reproductive system. They include height, voice, skin thickness and the quantity and distribution of body hair, muscles and adipose tissue (fat).


Acne is a skin disease that affects 90% of teenagers. It is usually not serious and typically disappears by the age of 20. At puberty, the increased production of sex hormones leads to the secretion of sebum and keratin, in greater quantities, by the sebaceous glands and the cells of the epidermis. The accumulation of sebum leads to inflammation of the hair follicles and encourages the spread of bacterium of the skin’s flora, Propionibacterium acnes. The result can be a variety of lesions: papules, pustules nodules and cysts. Acne treatment aim to stop the blockage of the pores and the spread of the bacteria.

Eating disorders

Eating disorders are psychological disorders characterized by a pathological relationship with food: anorexia nervosa, bulimia and hyperphagia.
Anorexia nervosa is an eating disorder characterized by the pathological fear of gaining weight and results in significant food restriction. It mainly affects young women in industrialized countries, particularly during adolescence. The disease, which may be undetected at first, causes several potentially serious issues: dehydration, cardiac problems, growth delay, dietary deficiency, etc. Treatment often requires hospitalization.
Bulimia is a disorder that is characterized by hyperphagia, meaning the uncontrollable and excessive ingestion of food, followed by compensation behavior: voluntary vomiting, excessive exercising, using laxatives and diuretics, etc. It results from sociocultural and psychological causes: low self-esteem, stress, depression, sexual abuse, etc. Bulimia does not cause significant weight fluctuations, but it can have serious health consequences leading to cardiac problems and serious digestive system problems.