How do a person's nutritional needs change from childhood through the teenage years, pregnancy and into old age?
Explain how nutritional needs change across the life cycle and justify the key nutrients for each life stage
A focused answer on how nutritional needs change across the life cycle - children, teenagers, pregnant women, adults and older adults - and the key nutrients each group needs and why.
Reviewed by: AI editorial process; not yet individually human-reviewed
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What this dot point is asking
The syllabus wants you to explain how nutritional needs change at different stages of life and to justify the key nutrients each group needs. The central idea is that the same balanced-diet principles apply to everyone, but the emphasis shifts: growth stages need more building nutrients, pregnancy supports a second body, and old age brings new risks.
The answer
Children
Children are growing and active, so relative to their size they need plenty of energy, protein for growth, and calcium with vitamin D for developing bones and teeth. Iron is needed for healthy blood. Because their stomachs are small, regular meals and nutritious snacks matter, and too much sugar should be avoided to protect teeth and prevent early weight gain.
Teenagers
Teenagers go through a rapid growth spurt and are often very active, giving them some of the highest energy and nutrient needs of any group. Key nutrients are protein (growth and repair), calcium and vitamin D (to build peak bone mass), and iron, which is especially important for girls who lose iron during menstruation and so are at higher risk of anaemia.
Pregnant and breastfeeding women
A pregnant woman must nourish her own body and a growing baby, so her needs rise. Key nutrients are folate (folic acid) early in pregnancy to help the baby's nervous system develop and prevent defects, iron to make extra blood and prevent anaemia, and calcium for the baby's bones and teeth. Energy and protein needs increase, more so during breastfeeding.
Adults
In adulthood the focus shifts from growth to maintenance and the prevention of diet-related disease. Energy needs depend on activity and should be matched to avoid weight gain, with attention to keeping saturated fat, sugar and salt moderate and fibre high.
Older adults
Older adults are usually less active and often eat less, so energy needs fall but the need for nutrients stays high - this is called nutrient-dense eating. They are at risk of low calcium and vitamin D (weak bones, osteoporosis), low iron (anaemia), and low fibre and fluid (constipation). Soft, easy-to-chew, nutrient-rich foods and enough fluids are important.
Examples in context
Example 1. A growing child's lunchbox. A balanced lunchbox for a primary-school child might include a wholemeal sandwich with egg or chicken (protein, iron), a small carton of milk (calcium), fruit, and water rather than a sugary drink. Small, frequent, nutrient-rich items suit a child's small appetite and protect developing teeth.
Example 2. Soft, nutrient-dense food for an elderly grandparent. Steamed fish porridge with finely chopped vegetables and a soft-boiled egg gives protein, iron and vitamins in a form that is easy to chew and swallow. It shows how the older adult's nutrient needs are met while respecting a smaller appetite and chewing difficulty.
Try this
- Cue. Explain why teenagers have especially high nutritional needs and name two key nutrients. Link the growth spurt and activity to protein and calcium (and iron for girls).
- Cue. State two nutrients a pregnant woman particularly needs and why. Recall folate to protect the baby's development and iron to make extra blood.
- Cue. Explain why food for older adults should be nutrient-dense. State that energy needs fall but nutrient needs stay high, so each portion must carry plenty of nutrients.
Exam-style practice questions
Practice questions written in the style of SEAB exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
Original6 marksExplain why teenagers and pregnant women have high nutritional needs, naming two key nutrients for each group and the reason each is needed.Show worked answer →
Teenagers are growing rapidly and are usually active, so they need plenty of energy and nutrients for growth. Two key nutrients: protein, for the growth and repair of muscle and tissue; and calcium (with vitamin D), to build strong bones during this growth spurt. Iron is also important, especially for girls who lose iron during menstruation.
Pregnant women must support the growth of the baby as well as their own body. Two key nutrients: folate (folic acid), to help the baby's nervous system develop and prevent defects; and iron, to make extra blood for both mother and baby and prevent anaemia. Calcium for the baby's bones is also important.
What markers reward: a clear reason each group has high needs (growth; supporting a developing baby), and two correctly justified nutrients for each.
Original5 marksAn older adult eats very little, often skips meals, and rarely goes outdoors. Explain three nutrients they may be lacking and the problems this could cause.Show worked answer →
Calcium and vitamin D: with little food and little sunlight, the adult may lack both. Vitamin D is needed to absorb calcium, so a shortage weakens the bones and can cause osteoporosis, raising the risk of fractures.
Iron: eating little, especially little meat, can lead to iron-deficiency anaemia, causing tiredness and weakness.
Fibre and fluid: eating and drinking too little can cause constipation. Protein may also be low, slowing wound healing and weakening muscles.
What markers reward: three sensible nutrients linked to the older adult's situation (low intake, little sunlight) and the specific problem each shortage causes.
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