Diet and Growth | Vitamins & Nutrients | PDF

Okay, here is the converted text from the images provided: ### Diet and growth #### Carbohydrates, fats, and proteins The image shows a plate of food containing rice, chicken, beans, avocado, and vegetables. There are several different kinds of food on the plate. How does each of these foods hel...

Okay, here is the converted text from the images provided: ### Diet and growth #### Carbohydrates, fats, and proteins The image shows a plate of food containing rice, chicken, beans, avocado, and vegetables. There are several different kinds of food on the plate. How does each of these foods help the body to stay healthy and have energy? The rice contains a lot of **starch**. Starch is a type of **carbohydrate**. After you have eaten starch, the body breaks it down to make a sugar called **glucose**. Glucose is the fuel that your cells use for respiration to release energy. So, starch, sugar, and other carbohydrates are needed to give you energy. The chicken and beans contain a lot of **protein**. Protein is important for making new cells in the body. So, you need protein to helpthe body grow or to repair itself if it gets damaged. Protein is also needed to make hemoglobin and antibodies. The avocado contains **fats** and **oils**. Fats and oils are very similar but at normal temperatures, fats are solid and oils are liquid. Fats and oils give you energy and are also needed to make cell membranes. ### 7.1 Nutrients Protein, carbohydrate, and fat are nutrients. Nutrients are substances found in food that you need to stay healthy. The image shows food sources of these nutrients. #### Energy stores You do not eat all the time, but you need energy all the time. You get almost all of your energy from the carbohydrates and fats that you eat. You can also get energy from protein if you run out of carbohydrates and fats. You store a little bit of carbohydrate and quite a lot of fat in your body. These energy stores provide you with energy whenever you need it. You store a small amount of carbohydrate in your cells, especially in the liver and muscles. These are short-term energy stores. For long-term stores, your body stores fat in special cells underneath the skin and around some of the body organs. Fat stores in the body also provide heat insulation. Animals that live in cold places, like the seal in the image, have a lot of fat stores underneath their skin to help stop them losing heat from their body. #### Vitamins Vitamins are nutrients that are needed in only small amounts, but if you don't eat them you can get ill. There are lots of different kinds of vitamin. Each kind is given a letter. **Vitamin A** Vitamin A is needed to help your eyes work well, so that your vision is good. It is particularly important for helping us to see when it is quite dark. People who don't have enough vitamin A in their diet may not be able to see anything at night. It also helps your white blood cells to fight pathogens. You get vitamin A by eating green vegetables, carrots and squash (such as pumpkin), fruit, foods made from milk (such as cheese), and some kinds of fish. **Vitamin C** Vitamin C helps the skin to stay strong and to heal quickly if it is damaged. It keeps blood vessels and bones healthy. People who don't eat enough vitamin C can get an illness called scurvy. A person with scurvy feels weak and may have swollen, bleeding gums. You get vitamin C by eating fresh fruit and vegetables. Citrus fruits are particularly rich in vitamin C. Potatoes and colorful berries are also good sources of vitamin C. In the past, before anyone knew about vitamin C, sailors on long sea voyages often got scurvy. This was because they had no fresh fruit or vegetables to eat. **Vitamin D** Vitamin D is needed for strong bones and teeth. It helps the body to absorb calcium from the food that you eat. There are not many kinds of food that contain vitamin D. Oily fish is probably the best source. But for most people, most vitamin D does not come from the food that you eat. Instead, vitamin D is made in the skin when sunlight falls onto it. People who never go outdoors, or who never get any sunlight on their skin, may not get enough vitamin D. This is most likely to happen if you live in a country far from the equator, or where there is not much sunshine. In children, lack of vitamin D can stop their bones growing normally. This illness is called rickets. ### 7.1 Nutrients **Activity 7.1.2** **Vitamins poster** * Work in a group of three for this activity. * You will need a big piece of paper, and some colored pens or pencils. * Divide the sheet of paper into three equal areas labeled Vitamin A, Vitamin C, and Vitamin D. * Use the information in this book, the Internet and/or the library to find out which foods contain a lot of each vitamin. * Draw pictures of the foods in each space. If you like, you could also cut out some pictures of foods from packaging or magazines, and stick the pictures onto your poster. #### Minerals There are several different kinds of **mineral** that you need to eat. Two of the most important ones are calcium and iron. **Calcium** Bones and teeth contain calcium, so you need to eat plenty of calcium to make them strong. Foods made from milk are excellent sources of calcium. Seeds and some types of nut (such as almonds) also contain a lot of calcium. **Iron** Iron is needed to make hemoglobin. If you don't eat enough iron, you don't make enough hemoglobin, so not enough oxygen is transported around the body. This causes an illness called **anemia**, which makes a person feel very tired. Good sources of iron include meat (especially red meat), dark green vegetables, many kinds of fish and shellfish, and some nuts and seeds. **Questions** 1. Look back at question 1. Draw a similar table, but include vitamin A, vitamin C, vitamin D, calcium, and iron instead of protein, carbohydrate, and fats. Then complete your table. 2. Use your knowledge about respiration to explain why a person with anemia does not have much energy. 3. These bell peppers are stuffed with lentils and vegetables, and topped with cheese. They contain a lot of iron and calcium. What other nutrients do you think this meal contains? Explain your answer. #### Water There is one more nutrient to add to the list of what you need to take into your body each day. This is water. Water is needed for many different purposes in the body. Cells and blood contain a lot of water. Almost $60\%$ of a person's body weight is made up of water. Water in cells allows all the different chemicals inside them to dissolve so that they can react together. These reactions keep us alive. Water in blood allows it to flow easily, transporting substances all over the body. #### Summary checklist * I can list the six types of nutrient that I need in my diet. * I can explain why I need each of these nutrients. * I can list some foods that contain each of these nutrients.