In this topic we are learning to: z Consider why one diet does not suit everyone. z Interpret food labels. z Plan a balanced diet to promote good health.
One diet does not suit everyone. Dietary choice has to account for a number of factors:
z Age z Gender z Genetics z Health z Physical activity.
A balanced diet provides carbohydrates, proteins, fats, vitamins, minerals, fibre and water in the correct quantities.
Energy From Food
Learn more about energy and joules in Physical World 16.1
The quantities of biomolecules in food are given in grams (g). One gram is equal to one thousandth of a kilogram (kg).
Energy values for different foods can normally be found on a nutritional label on the food’s packaging. As a joule is a small quantity of energy, the energy in foods is measured in thousands of joules, or kilojoules (kJ). On food labels, the energy content can also be given in kilocalories – 1 kcal is equal to 4.2 kJ.
Fig. 2.2.2
A nutritional label showing the energy values of a typical food serving
Fig. 2.2.1 We need to drink more water when we exercise
F A typical person requires
approximately 2.5 litres of water a day. Of course, we need to drink more if we exercise or if it is a hot day.
