Growing Up Well: Nutrition for Children and Teenagers

This is Part 2 of our Nutrition Through the Ages series. Part 1: Pregnancy and Babies | Part 3: Adults and Ageing

Between the ages of 2 and 18, a human body goes through more change than at any other period except infancy. Bones are lengthening. Brains are developing. Hormones are surging. Immune systems are maturing. And all of this runs on whatever fuel the child puts in, which increasingly becomes their choice rather than yours.

The nutritional priorities shift as children grow, and the practical challenges shift even more dramatically. A toddler who throws broccoli on the floor is a different problem from a teenager who lives on meal deals and energy drinks.

Toddlers (1-3 years): the fussy eating years

Almost every toddler goes through a phase of food refusal. This is normal. It is developmental, not defiance. Toddlers are asserting autonomy over one of the few things they can control, and their appetite genuinely fluctuates as growth rates vary.

What actually helps with fussy eating:

Repeated exposure without pressure. Research consistently shows that children may need to see, touch, or taste a food 10-15 times before accepting it. Offering it once, having it rejected, and never offering it again is the most common mistake parents make. Keep putting small amounts of rejected foods on the plate alongside accepted foods. No comments, no bribes, no battles.

Eat together. Children learn eating behaviour by watching. If they see you eating vegetables with apparent enjoyment, they are far more likely to try them. If vegetables only appear on their plate and not on yours, the message is clear.

Involve them. A toddler who helps wash the tomatoes or stir the porridge is more invested in the result. This is not about creating a tiny chef. It is about creating familiarity with food as something interesting rather than threatening.

Do not use food as reward or punishment. "Eat your peas and you can have pudding" teaches children that peas are the price of admission and pudding is the prize. It elevates sweet food and diminishes vegetables. Serve pudding (if you are having it) as part of the meal, not as a conditional reward.

Nutritional priorities for toddlers: Full-fat dairy (semi-skimmed milk only from age 2, skimmed only from age 5). Iron (toddlers are one of the highest-risk groups for iron deficiency in the UK). Vitamin D (supplement of 10mcg daily recommended for all children aged 1-4). Calcium for rapid bone growth. Limit fruit juice and squash (tooth decay risk, and liquid calories displace appetite for actual food).

Primary school age (4-11): building habits

By this stage, taste preferences are becoming more established and the window for shaping them, while not closed, is narrowing. The school environment introduces new influences: packed lunches, school dinners, what friends eat, what gets swapped in the playground.

What matters most at this age:

Breakfast. The evidence that breakfast improves concentration and academic performance in children is strong. A bowl of porridge, wholemeal toast with peanut butter, or eggs provides sustained energy through the morning. Sugary cereals (Coco Pops, Frosties, and their equivalents) deliver a blood sugar spike followed by a crash that coincides with mid-morning lessons. If your child will only eat sugary cereal, mix it half-and-half with a plainer option and gradually shift the ratio.

Packed lunch quality varies enormously. A typical packed lunch of a white bread sandwich, a packet of crisps, a chocolate biscuit, and a juice carton is nutritionally poor. Better: wholemeal pitta with hummus and cucumber, a piece of fruit, a small handful of nuts (check school allergy policies), a pot of yoghurt, and water.

School dinners have improved since the Jamie Oliver era but vary widely between schools. Look at the menu. If it includes daily vegetables, protein options, and wholegrain carbohydrates, school dinners may be a better option than a hastily assembled packed lunch.

Snacking. Children need snacks between meals because their stomachs are small and their energy demands are high. The question is what they snack on. Fruit, vegetable sticks with hummus, plain yoghurt, rice cakes with peanut butter, cheese and crackers, and a small handful of nuts are all vastly better than biscuits, crisps, and sweets. Make the healthy option the easy option: have it washed, cut, and at the front of the fridge.

Teenagers (12-18): the independence challenge

Puberty changes everything. Calorie requirements increase significantly (teenage boys may need 2,500-3,000 calories per day during growth spurts). Nutrient requirements for iron, calcium, and zinc peak. And parental control over food choices drops off a cliff.

The specific nutritional risks for UK teenagers:

Iron deficiency. Teenage girls are at particularly high risk due to menstruation combined with diets that are often low in red meat and legumes. Symptoms include fatigue, poor concentration, and frequent illness. A full English breakfast on Sunday does not compensate for iron-poor eating the rest of the week.

Calcium. Peak bone mass is built during adolescence. The calcium laid down during the teenage years determines bone density for life. Teenagers who avoid dairy and do not replace it with fortified alternatives are compromising their skeleton before it is fully built.

Energy drinks. The UK has no legal age restriction on energy drinks, though most supermarkets voluntarily restrict sales to under-16s. A single 500ml can of Monster contains 160mg of caffeine (equivalent to two espressos) plus large amounts of sugar. For a 13-year-old weighing 45kg, this caffeine dose is substantial and can cause anxiety, insomnia, heart palpitations, and difficulty concentrating. The irony is that teenagers drink them to feel more alert, while the sleep disruption makes them more tired the next day.

Disordered eating. The teenage years are when eating disorders most commonly emerge. Warning signs include skipping meals regularly, obsessive calorie counting, eliminating entire food groups without medical reason, excessive exercise driven by body image, and comments about needing to "be smaller." If you notice these signs, speak to your GP. Early intervention significantly improves outcomes.

Practical strategies for teenagers:

You cannot control what they eat outside the house. You can control what is available inside it. Stock the kitchen with foods you are happy for them to eat. If there are no biscuits in the cupboard, they will eat the fruit, the nuts, or the toast instead.

Teach them to cook three or four basic meals. Pasta with a simple sauce. A stir-fry. Eggs on toast. A basic curry. These skills are genuinely life-changing for the transition to university or independent living, and a teenager who can cook is a teenager who does not need to rely on takeaways.

Do not comment on their weight. Comment on their energy, their strength, their health, their mood. Body-focused comments from parents, even well-intentioned ones, are consistently linked with disordered eating in research.

How MyFoodFit helps families

The app can be used by any family member with their own dietary profile. A parent scanning products at the supermarket can quickly check whether something is a good choice for a child with a nut allergy, a teenager who needs more iron, or themselves managing a health condition.

The scoring does not moralise. A product is not "bad." It just scores higher or lower for a given profile. This framing is particularly important for teenagers, for whom food guilt and restriction can be genuinely harmful. The goal is information, not judgement.

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This content is for information only and does not replace medical advice. If you have concerns about your child's eating, growth, or relationship with food, speak to your GP or health visitor.