Describe how nutritional needs change across the life stages and explain the key nutrients for each group

What this dot point is asking

SEAB wants you to describe how a person's nutritional needs change through life and to explain the key nutrients for each stage. The big idea is that the body's job changes with age: babies and children are growing fast, teenagers have a growth spurt, pregnant women feed a growing baby, and the elderly need to protect bones and digestion. The marks come from matching each group to the nutrients it especially needs, with a clear reason.

The answer

Babies and young children

A new baby is fed milk (breast milk or formula) because it supplies all the nutrients in an easily digested form before the baby can eat solids. As children grow they need protein for building tissue, calcium and vitamin D for growing bones and teeth, and iron for healthy blood, all in smaller portions suited to their size.

Teenagers

Teenagers go through a fast growth spurt, so their needs are high:

• Protein for the growth of new tissue and muscle.
• Calcium and vitamin D to build strong bones, which reach much of their peak strength in the teenage years.
• Iron, especially for girls once menstruation begins, to replace blood loss.
• Plenty of energy for growth and an active lifestyle.

Adults

A healthy adult who has stopped growing needs a balanced diet for maintenance and repair rather than growth. Energy needs depend on body size and activity, and adults should watch their fat and free sugar to avoid weight gain and diet-related disease.

Pregnant and breastfeeding women

A pregnant woman is nourishing a growing baby as well as herself, so she needs more of several nutrients:

• Protein for the baby's growing tissues.
• Iron to make extra blood and supply the baby, preventing anaemia.
• Calcium and vitamin D for the baby's bones and teeth.
• Folate (folic acid) for the healthy development of the baby's nervous system.

The elderly

In older age, growth has long stopped and activity is often lower, so energy needs fall, but quality stays important:

• Calcium and vitamin D to keep bones strong and reduce the risk of osteoporosis and fractures.
• Fibre and water to prevent constipation, which is more common with age.
• Enough protein to maintain muscle, in soft, easy-to-eat forms if chewing is hard.

Examples in context

Example 1. A teenager's bone-building diet. A secondary school student who drinks milk, eats tofu and small fish with bones (such as ikan bilis), and gets some sun is building strong bones during the teenage years when bone strength peaks. Falling short of calcium and vitamin D now means weaker bones later, which is why this life stage matters so much for the skeleton.

Example 2. Soft, nutritious meals for a grandparent. An elderly person who finds chewing hard can still meet their needs with soft, nutrient-rich dishes such as steamed fish, soft tofu, porridge with minced meat and vegetables, and yoghurt. These supply protein and calcium in an easy-to-eat form, showing how the same nutrients are delivered differently for an older life stage.

Try this

Q1. Explain why teenagers need plenty of protein and calcium. [2 marks]

• Cue. They are in a growth spurt, so protein builds new tissue and calcium builds strong bones reaching peak strength.

Q2. State two nutrients a pregnant woman needs more of, with a reason for each. [4 marks]

• Cue. Iron (to make extra blood and prevent anaemia); calcium (for the baby's bones); protein (for the baby's tissues); folate (for the baby's nervous system) - any two with reasons.

Q3. Explain why an elderly person should have enough fibre and water. [2 marks]

• Cue. To prevent constipation, which is more common in older age; fibre adds bulk and holds water to keep the bowels moving.