Healthy habits and nutrition
Explain how activity, rest, hygiene and each nutrient in a balanced diet support the body.
On this page
Staying Healthy · about 25–35 min
What you need to understand
Name the need, then explain how the choice supports it.
Definitions
- balanced diet
food and drink supplying suitable amounts of energy, nutrients, fibre and water for a person’s needs
For example: Balance does not mean equal masses of every food.- nutrient
a substance in food needed for energy, growth, repair or healthy body processes
For example: Protein supports growth and repair, while calcium supports bones.
Explanation
Activity, balanced eating, rest and hygiene meet different needs. In a fictional school day, a learner needs food and water for the day, time to move, recovery and sleep, and handwashing before handling food. Replacing every break with exercise would not meet all these needs.
A balanced diet supplies suitable amounts and variety for a person’s needs. It does not mean equal masses of every food. The roles below explain why one dietary component cannot replace all the others.
| Component | What it helps the body do | Example source |
|---|---|---|
| Carbohydrate | Supply energy released in respiration | Rice or bread |
| Dietary fibre | Add bulk to stools and, with enough water, help them pass through the gut | Vegetables or wholegrains |
| Fat | Supply energy and help absorb fat-soluble vitamins such as vitamin D | Oils or nuts |
| Protein | Grow and repair tissues | Beans or eggs |
| Calcium | Build and maintain bones | Milk or a calcium-fortified plant drink |
| Vitamin D | Help the body absorb calcium | Oily fish or foods labelled as fortified with vitamin D |
| Water | Dissolve substances for transport and help regulate temperature, including through sweating | Water and other drinks |
Many foods contain more than one dietary component. The examples are sources,
not a complete meal plan. Explain choices by their roles rather than calling
foods or bodies good or bad. The NHS explanation of calcium and vitamin D
Pause and say it: Name the need, then explain how the choice supports it.
Common mistake
Tempting wrong idea: A single dietary component can replace a balanced diet.
Why it fails: One nutrient or one habit cannot meet every need. More activity does not replace food, rest or hygiene.
Use this instead: Water is needed, but it cannot replace energy, protein, fibre and other dietary components. A balanced diet supplies suitable types and amounts.
Worked Example
Modelled example 1
Which needs does the plan meet?
Problem
In a fictional school-day plan, Sam proposes skipping lunch and replacing every rest break with exercise. Sam says this will meet every health need. Explain what the plan overlooks without giving a weight target.
Study the worked solution
Separate the needs
Method
Identify what food, activity and rest each contribute.
Reason
One habit cannot replace the functions of the others.
Working
Food supplies energy and nutrients; activity supports physical functioning; rest supports recovery. Handwashing and other hygiene practices reduce transfer of harmful microbes. Extra activity does not supply nutrients or replace recovery.
Improve the reasoning
Method
Include suitable food, movement, rest and hygiene.
Reason
A balanced plan meets several needs, rather than maximising one activity.
Working
Sam’s proposed substitutions leave important needs unmet. Explain which needs a choice supports; do not label a body or food as good or bad or prescribe restriction.
Guided practice
Try it with support
Match each nutrient to one role: carbohydrate, fibre, fat, protein, calcium, vitamin D and water.
Use energy, gut movement, growth and repair, bones, and transport or temperature control.
Check the guided answer
Answer: Carbohydrate supplies energy; fibre supports gut movement; fat supplies energy and supports cells; protein supports growth and repair; calcium supports bones; vitamin D supports calcium use; water acts as a solvent and supports transport and temperature control.
Check: A balanced diet supplies suitable amounts, not equal masses of every food.
Practise and continue
Practise this
Why should health advice consider activity, diet, rest and hygiene together?
Need a hint?
No single behaviour covers every need.
Check your answer
Answer: The factors support different needs and interact; for example, activity without enough food or recovery can cause fatigue or injury rather than better health.
Check: State how a behaviour supports health without promising a guaranteed outcome.
Think like a scientist
A fictional learner chooses only protein-rich food because protein helps growth. Explain the first error.
Check the reasoning
Growth also needs energy and a range of nutrients; fibre and water have roles too. One nutrient group cannot replace a balanced diet.
Remember: Avoid food bans or a personal diet prescription; explain the missing roles.
One-minute check
Hide the page. Explain why activity, a balanced diet, rest and hygiene meet different needs.
Name the roles of protein, calcium, vitamin D, fibre and water. Explain why protein alone cannot replace a balanced diet.
Correct this common mistake: “A single dietary component can replace a balanced diet.”
Syllabus and review details
- SEC G1 Science 2027 · 2027
Content structure and syllabus content, PDF pages 8–17
Last reviewed: