Diet and Good Health

You are what you eat, over time

A single meal does little, but what you eat over months and years shapes your health. At the centre of it is energy balance: the energy you take in from food and drink against the energy your body uses. - If energy IN equals energy OUT, your weight stays about the same. - If energy IN is greater than energy OUT for a long time, the surplus is stored and weight rises. - If energy IN is less than energy OUT, weight falls. Your energy needs depend on your BMR, the energy your body needs at rest, and your PAL, how active you are. Diet is also linked to several health conditions, including obesity, cardiovascular disease, type-2 diabetes, anaemia, and poor bone and dental health. This module works through energy balance, planning a balanced diet across life, and those conditions.

Words for diet and energy

Five terms you need before you use them. Learn what each one means.

Match the condition to its dietary link

Surplus against deficit

The direction of your energy balance, kept up over time, is what changes body weight. Both directions matter.

Name the condition

A person eats very little iron over a long period and becomes tired and pale. Which diet-related condition are they most likely developing?

• anaemia
• obesity
• type-2 diabetes
• tooth decay

Spot the true diet facts

Tap the TWO statements that are true.

• A long-term energy surplus leads to weight gain
• Too much saturated fat and salt raises the risk of cardiovascular disease
• A single unhealthy meal on its own causes long-term disease
• Too much sugar is the main cause of weak bones

Balancing energy and life stage

Two ideas help you plan a healthy diet for anyone. Match energy in to energy out. An athlete or a growing teenager uses a lot of energy and needs more; someone less active needs less. The aim is balance, not simply eating little. Adjust the nutrients to the life stage. A young child needs plenty of calcium for growing bones; a teenager needs energy and, especially, enough iron; an older adult needs calcium and vitamin D to keep bones strong; a pregnant woman has extra needs of her own. ⚠️ A balanced diet is not one fixed menu. It shifts with how active a person is and with their stage of life, and a good answer always says for WHOM.

Work out the balance

In one day a person takes in 2500 units of energy from food and uses 2000 units. Work out the energy surplus by taking the energy used away from the energy taken in.

Diet and the heart

Select the TWO things that, eaten in excess over time, most raise the risk of cardiovascular disease.

• saturated fat
• salt
• iron
• water

Order the road to weight gain

Put the stages by which a lasting energy surplus leads to a health risk in order.

• A person regularly takes in more energy than they use
• The surplus energy is stored in the body as fat
• Body weight rises steadily over time
• The risk of obesity and related conditions increases

Planning for a life stage

Here is how to adjust a diet to the person, worked through for two very different eaters. A growing teenager uses a lot of energy and is still building their body, so they need enough overall energy, plenty of protein for growth, and good sources of iron, which many teenagers fall short of. An older adult is usually less active, so needs less overall energy, but still needs strong bones, so calcium and vitamin D stay important, from foods such as dairy and oily fish. Notice the method: first ask how active the person is and what their body is doing at this stage, then choose foods that meet those needs. The same balanced-diet idea is tuned to each person rather than applied as one fixed plan.

Complete the diet facts

The energy the body needs at rest just to stay alive is the _____. When energy taken in is greater than energy used over time, the surplus is stored and body weight tends to _____. Too little iron in the diet over time can cause _____. A diet high in saturated fat and salt raises the risk of _____ disease.

Build the energy rule

Choose the words that complete the rule for a healthy weight.

Advise on the diet

Read each case and choose the best advice, then think about why.

• A fairly inactive adult keeps taking in much more energy than they use, day after day. What is the likely long-term result?
• A parent wants to protect the growing bones of a young child through diet. Which nutrients matter most here?
• A teenager lives mostly on sugary drinks and snacks. Which two health risks does this most raise?

Explain diet and health

A student in the year below thinks diet only matters for how you look. Explain how diet affects health, using what this module has covered.

• Explain what energy balance is and how it affects body weight
• Explain what BMR and PAL mean and why they change energy needs
• Explain how the right diet changes across two different life stages
• Explain two diet-related health conditions and the dietary link to each
• Finish by explaining why a balanced diet is tuned to the person, not one fixed menu