WHY WE EAT WHAT WE EAT EXPLORING ENERGY

WHY WE EAT, WHAT WE EAT EXPLORING ENERGY PART 1 – ENERGY OUT

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART I – ENERGY OUT • We all need energy to carry out our bodily functions, such as thinking, breathing and sleeping. • Energy can be measured in calories (kcal) or in joules (KJ) 1 Kcal = 4. 184 KJ

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART I – ENERGY OUT • The amount of energy we need to carry out our basic bodily functions at rest is called our Basal Metabolic Rate (BMR) • Everyone’s BMR differs according to their age, gender, weight, and physical health • Children also need energy to GROW

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART I – ENERGY OUT • In addition to the energy we need to keep our bodies running and to grow, we also need additional energy to make our bodies move around and do work, or physical activity • The more active we are the more energy our body requires

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART I – ENERGY OUT Different activities use different amounts of energy. Which activity below do you think uses the most energy? Cycling 186 kcal/hour Housework 102 kcal/hour Dancing 252 kcal/hour Football 330 kcal/hour

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART I – ENERGY OUT Different activities use different amounts of energy. Which activity below do you think uses the least energy? Gymnastics 236 kcal/hour Walking the dog Playing video 114 kcal/hour games 90 kcal/hour Housework 102 kcal/hour

WHY WE EAT, WHAT WE EAT EXPLORING ENERGY PART 2 – ENERGY IN

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 2 – ENERGY IN • All foods and drinks provide energy apart from water • Energy comes from three different nutrients in the foods we eat: – Carbohydrate (1 gram = 4 Kcal) – Protein (1 gram = 4 Kcal) – Fat (1 gram = 9 Kcal) • Fat provides more than double the amounts of energy per gram. So foods which contain a lot of fat also contain a lot of calories.

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 2 – ENERGY IN Which food item below do you think contains the most energy? Crisps 530 kcal/100 g Baked potato 136 kcal/100 g Boiled eggs 147 kcal/100 g Grapes 60 kcal/100 g

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 2 – ENERGY IN Which food item below do you think contains the least energy? Chocolate cake Boiled pasta 358 kcal/100 g 159 kcal/100 g Lentils 105 kcal/100 g Boiled sweets 327 kcal/100 g

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 2 – ENERGY EQUALS 75 g = ? calories 133 = ? minutes walking the dog 70 = ? minutes swimming 30

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 2 – ENERGY EQUALS 1 Big Mac = ? calories 490 = ? minutes walking the dog 258 = ? minutes swimming 117

WHY WE EAT, WHAT WE EAT EXPLORING ENERGY PART 3 – ENERGY BALANCE

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 3 – ENERGY BALANCE • If we eat the same amount of energy from food than we need then we are said to be in energy balance • However if we take in more energy than we use then we store the excess energy as fat • This leads to weight gain and eventually to overweight and obesity

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 3 – ENERGY BALANCE

WHY WE EAT WHAT WE EAT EXPLORING ENERGY PART 3 – ENERGY BALANCE • In order to maintain body weight, energy intake through food needs to balance energy expenditure • It is easier to maintain a healthy weight, than it is to lose excess weight