Teenagers and growth
During the growth spurt, the need for energy, protein, iron and calcium rises faster than at any point since infancy. At the same time, sleep patterns, eating habits and independence all change.
In short
What happens during the growth spurt?
Puberty brings rapid growth in height, increased muscle mass and the building of bone. The body essentially rebuilds itself over a few years, and that takes both energy and building blocks.
The need for iron, calcium, vitamin D and protein rises markedly. At the same time the body clock shifts, and many eat more outside the home than before.
This isn't about training and performance — it's about ordinary growth in ordinary teenagers.
Glossary
- Growth spurt
- The period of fastest growth in height, often 11–13 for girls and 13–15 for boys.
- Peak bone mass
- The highest bone mass the body reaches, largely determined in the teenage years.
Does this sound familiar?
This might sound like your situation
The teenage years bring big swings in appetite and routine — that's normal, but the need for nutrition is real.
- A growth spurt with sharply increased appetite
- Irregular meals because of school and activities
- A teenager eating vegetarian or vegan on their own initiative
- Girls with heavy periods and a risk of low iron
- Growing preoccupation with body, weight or diet
SmartEating recommends
What makes the biggest difference?
Five steps that cover the essentials during the growth years.
Enough energy
Under-eating during the growth spurt affects both height growth and concentration.
Iron every day
Meat, fish, eggs, legumes and wholegrains — ideally with vitamin C-rich food.
Calcium and vitamin D
Dairy or fortified plant drinks build bone while the window is open.
Regular meals
Breakfast, lunch, dinner and a couple of snacks give steady energy through the school day.
Talk about food, not weight
Focusing on energy, strength and capacity works better than conversations about body and weight.
When should you see a doctor?
- Growth stalling or unintentional weight loss
- Periods that never start or that stop
- Persistent fatigue, paleness or dizziness
- Signs of an eating disorder or intense control around food
If an eating disorder is suspected, contact your doctor early. Nutrition follow-up then happens alongside treatment.
Common questions
What people ask us most often.
Is it normal that my teenager eats constantly?
Yes. Energy needs rise sharply during the growth spurt, and frequent hunger is usually a healthy sign that the body is growing.
Do teenagers need supplements?
Most cover their needs through food, apart from vitamin D in winter. With a plant-based diet or low iron, supplements may be relevant after assessment.
What if my teenager wants to stop eating meat?
It is entirely possible to cover the need, but iron, vitamin B12, calcium and protein should be planned deliberately. A review with a professional gives peace of mind.
Personal nutrition
No two people with teenagers and growth are the same
Some train a lot, some have several symptoms at once, some are pregnant, some have low values on blood tests and some have a busy family life.
That is why people in the same situation need different advice. SmartEating AI learns your situation over time and adapts suggestions to your body, goals and everyday life.
A clinical dietitian assesses whether the diet covers growth and development, and gives advice the teenager can use themselves.
We work practically with breakfast, school food and snacks — without diets, counting or a focus on weight.
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The knowledge behind the advice
Adolescents
The teenage years bring rapid growth, hormonal changes, and increasing independence around food choices. The need for energy and certain nutrients rises significantly, while school, social life, and any sports commitments place demands on daily meal structure.
Calories and energy
Calories measure the energy in food and drink, and energy balance is a fundamental principle of weight development. But counting calories alone says little about food quality, satiety or health effects.
Children
The childhood years lay the foundation for eating habits, growth, and a relationship with food that often lasts a lifetime. Nutritional needs change rapidly through childhood, and the focus should be on varied, energy-dense, and safe food in a calm mealtime environment.
Assessment
A digital form before the session so the specialist knows your situation.
Kick-off conversation
60 minutes online or at a partner clinic.
Personal plan
A concrete plan in SmartEating — food, structure and goals tailored to you.
Ready to get help with teenagers and growth?
We'll connect you with a licensed clinical dietitian who understands your situation.
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