Nutritional Needs, Life Stages and Diet Planning
Guidelines for a Healthy Diet — The Eatwell Guide
The Eatwell Guide is the UK government’s model for a balanced diet. It divides food into five groups and shows roughly what proportion of your plate each should occupy. Because the exam focuses on applying the guide to real meals rather than simply listing percentages, it is worth understanding what each segment means in practice.
- Fruit and vegetables (roughly one third of the plate) — include fresh, frozen, dried, canned and juiced varieties. At least five 80 g portions per day is the guidance. They supply vitamins, minerals, fibre and antioxidants.
- Starchy carbohydrates (roughly one third) — bread, pasta, rice, potatoes, oats. Choose wholegrain versions where possible for more fibre and B vitamins.
- Dairy and dairy alternatives — milk, cheese, yoghurt, and fortified plant milks. Main sources of calcium and iodine.
- Protein foods — beans, pulses, fish, eggs, meat and meat alternatives (TVP, tofu, mycoprotein). Eat at least two portions of fish per week, one of which should be oily.
- Oils and spreads — use in small amounts and choose unsaturated options (olive oil, rapeseed oil) rather than butter or lard.
Foods high in fat, salt and sugar — biscuits, cakes, crisps, fizzy drinks — are shown outside the main segments. They are not necessary for a healthy diet and should be eaten less frequently and in small amounts.
The Eatwell Guide has five food groups. Fruit and vegetables and starchy carbohydrates each form roughly one third of the daily plate. Protein foods, dairy and dairy alternatives make up most of the rest. Oils and spreads are used in small amounts. Foods high in fat, salt and sugar sit outside the guide.
Portion Size and Costing
When planning a meal, portion size matters for both nutrition and cost. A portion of meat or fish is typically 80–100 g; a portion of cooked pasta or rice is around 180 g. Planning meals in advance, writing a shopping list, using seasonal ingredients, buying own-brand products, and avoiding food waste all reduce the cost of a balanced diet. Costing a recipe means calculating the ingredient cost per serving: divide the cost of the whole pack by the number of portions the pack makes, then add up all the ingredient costs for one serving.
How Nutritional Needs Change Across Life Stages
The body’s needs are not fixed throughout life. Growth, hormone changes, activity levels and the gradual slowing of metabolism all shift what nutrients we need most. The exam lists four life stages to know in detail.
Young Children (1–5 years)
Young children are growing rapidly and need relatively high energy, protein, calcium and vitamin D for bone development. However, their stomachs are small, so meals should be nutritionally dense rather than bulky. Whole (full-fat) milk rather than skimmed milk is recommended up to age 2 because growing toddlers need the fat and fat-soluble vitamins. Salt intake should be kept very low (less than 2 g/day for children aged 1–3). Young children are at higher risk of iron deficiency because they are growing fast; iron-rich foods (red meat, fortified cereals, beans) should be included regularly.
Teenagers
Adolescence brings the biggest growth spurt since infancy. Teenagers have high energy needs, especially if active, and need more protein for muscle development. Calcium and vitamin D are critical: bone density peaks in your early twenties, so what you eat during your teenage years directly affects your risk of osteoporosis decades later. Teenage girls who have started their periods have significantly higher iron needs than boys (because of menstrual blood loss) — and iron-deficiency anaemia is one of the most common nutritional deficiencies in adolescent girls. Folate is also important for all teenagers for healthy cell division.
Adults
Adults have lower energy needs relative to body size than teenagers. The focus shifts to maintaining a healthy body weight, keeping cardiovascular risk low (limiting saturated fat and salt), and eating adequate fibre to reduce the risk of bowel disease and type 2 diabetes. Pregnant and breastfeeding women have additional requirements: folic acid in the first trimester reduces the risk of neural tube defects; iron supports the growing foetus and replaces maternal losses; calcium and vitamin D support fetal bone development; and energy needs increase in the third trimester and during breastfeeding.
The Elderly
Older adults have lower total energy needs because metabolism slows, but their need for protein, calcium, vitamin D and B12 remains high or even increases. Many elderly people have reduced appetite and may be less active, making every mouthful count nutritionally. Vitamin D synthesis in the skin declines with age, and many older adults spend less time outdoors; supplementation is widely recommended. Risk of osteoporosis increases, making calcium intake critical. Dehydration is common in the elderly because the sense of thirst becomes less reliable with age.
Teenage girls need more iron (to replace menstrual losses) and calcium (for peak bone density). Elderly adults need vitamin D (skin synthesis declines), calcium (osteoporosis risk) and vitamin B12 (absorption declines with age) despite lower overall energy needs.
Planning for Specific Dietary Groups
The exam expects you to plan a balanced meal for four specific dietary groups. Each one requires thought about nutrient gaps and practical substitutions.
A vegetarian diet excludes meat and fish. A vegan diet excludes all animal products. Both must plan carefully to avoid deficiencies. Key nutrients at risk in vegan diets: vitamin B12 (only in animal foods or fortified products), vitamin D (few dietary plant sources), calcium (dairy is the main UK source — must use fortified plant milks or eat plenty of kale and tofu), iron (non-haem iron from plant foods is less well absorbed — eat with vitamin C), omega-3 fats (oily fish is absent — flaxseed, walnuts, algae-based supplements). Protein: use complementation and soya/tofu/mycoprotein.
Coeliac disease requires a strict gluten-free diet. Gluten is found in wheat, barley and rye — so ordinary bread, pasta, biscuits and cakes are off-limits. Substitutes include rice, maize (corn), potatoes, gluten-free oats, and purpose-made gluten-free products. Cross-contamination in the kitchen must be prevented. Lactose intolerance means the person cannot digest lactose, the sugar in cow’s milk, due to insufficient lactase enzyme. Symptoms include bloating and diarrhoea. Alternatives: lactose-free milk, hard cheeses (lower in lactose), small amounts of yoghurt (fermentation reduces lactose), and calcium-fortified plant milks. A high-fibre diet benefits people at risk of constipation, bowel disease or type 2 diabetes. It should include wholegrain bread and cereals, plenty of vegetables and pulses, and fruit.
Maintaining a Healthy Body Weight
A healthy body weight is maintained when energy intake equals energy expenditure — this is called energy balance. Regular physical activity, eating plenty of fibre (which promotes satiety), limiting high-fat and high-sugar foods, and eating regular meals (which prevents extreme hunger leading to overeating) all support a healthy weight throughout life. Making informed food choices means reading labels, understanding portion sizes, and choosing cooking methods that add less fat (grilling rather than frying, baking rather than deep-frying).