Adolescence (approximately 12-18 years old) is a period of extraordinary transformation: puberty brings a height increase of 20-30 cm, a weight gain of 20-25 kg, profound hormonal changes, critical bone development, increased muscle mass (especially in males), accumulation of body fat (especially in females). All this growth requires nutrients in quantities higher than those of adults for almost every category. Paradoxically, this is the period when eating habits tend to deteriorate: skipped meals, fast food, snacks, energy drinks replace the balanced family diet.

Calcium: building bones for life

90% of bone mass is deposited by age 18. Adolescence is the critical window for bone mineralization: the calcium accumulated during these years determines the peak bone mass that will protect against osteoporosis after age 50. The calcium requirement for adolescents (1,300 mg per day) is higher than for adults (1,000 mg) and the elderly. Main sources: dairy products (200 mg per serving), sardines with bones, calcium-fortified tofu, broccoli, kale, fortified plant-based milk. A typical adolescent diet with little attention to dairy and many substitute beverages can easily result in only 600-700 mg per day: half of what's needed.

Iron: different needs for boys and girls

With puberty, iron requirements change dramatically and differently for the two sexes. In girls, the onset of menstruation increases monthly iron losses significantly: the requirement rises to 18 mg per day (compared to 8 mg for pre-pubescent girls). In boys, the rapid expansion of muscle mass and blood volume increases the requirement to 11 mg per day. Iron deficiency anemia is very common in adolescent girls: it affects 10-15% of Italian girls of reproductive age. Often-overlooked symptoms: chronic fatigue, pallor, difficulty concentrating, reduced academic and athletic performance. Iron sources: lean red meat (2-3 times per week), legumes, whole grains, always paired with vitamin C.

Protein: building the changing body

Adolescence is the period of greatest increase in muscle mass, especially in boys. The protein requirement is 0.85-1g per kg of body weight per day (slightly higher than adults). For a 60 kg adolescent: approximately 50-60g per day. For athletic adolescents: 1.2-1.6g per kg. A diet that regularly includes meat, fish, eggs, and legumes easily meets this requirement. The problem is often meal irregularity: adolescents who skip breakfast, eat little at school lunch, and then compensate in the evening with protein-poor snacks.

Zinc: puberty and sexual development

Zinc is essential for the production of sex hormones, testicular development in males, and follicle maturation in females. The requirement in adolescents (males: 11 mg, females: 9 mg) is higher than in children. Zinc deficiency delays puberty and compromises sexual development: it's one of the first identified causes in areas of the world with nutritional deficiency, but can also occur in adolescents in developed countries with very selective diets (persistent food neophobia, unplanned vegan diets). Sources: meat, pumpkin seeds, legumes, whole grains.

Vitamin D: often deficient in adolescents

Italian adolescents are among the groups with the highest prevalence of vitamin D deficiency: they spend many hours in enclosed environments (school, study, video games), use sun protection during exposure hours, and many eat little fatty fish. Yet vitamin D is critical during this period for: bone mineralization (it works together with calcium), immune function, mood regulation (deficiency is associated with adolescent depression). Check vitamin D levels in adolescents who show chronic fatigue, depressed mood, frequent infections, or reduced athletic performance.

How to ensure calcium for an adolescent who won't drink milk

If the adolescent refuses milk (common, due to taste or vegan tendencies): Greek yogurt (the thick consistency is often more acceptable than liquid milk), kefir (fermented beverage that many adolescents find more interesting than milk), cheeses (parmesan, mozzarella, emmental: often already present in the diet), fortified plant-based milk (oat or soy with at least 120 mg of calcium per 100 ml), sardines (if accepted), tofu with calcium sulfate. Three servings of these foods per day guarantee the necessary 1,300 mg even without milk.

The weekly plan for adolescent nutritional needs

Every day: a source of calcium at each meal (dairy product, fortified plant-based milk, calcium-rich vegetables), iron with vitamin C at least at one meal (legumes or meat with tomatoes, peppers, citrus), protein distributed across the three main meals. Three times a week: fatty fish (sardines, salmon, mackerel) for omega-3s and vitamin D. Every week: verify that breakfast always includes something solid (not just coffee or nothing). The main problem for the adolescent isn't what they eat at dinner: it's what they skip during the school day and study hours.

Talking about nutrition with an adolescent: how to do it without conflict

Adolescents respond poorly to food impositions (as to any imposition). They respond better to: involvement in choices ("what do you want to eat this week? Look at the options here"), motivations that resonate with their values (athletic performance, energy for studying, glowing skin, strong hair: not "it's good for your health" in the abstract), gradual autonomy in food preparation, the social aspect of food (cooking with friends, exploring different cuisines). Don't make nutrition a battlefield: it's a war that parents almost always lose with adolescents.