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producing red blood cells and preventing birth defects. See the appendix for a list created by the Food and Drug Administration (FDA) that explains how much of each vitamin and mineral you need, and how much of it you need per day. Why Do I Need Protein? You’ve probably heard that people are mainly made of water—around 60 percent of the human body is water. After water, the next most plentiful component of the human body is protein. Proteins come in a lot of different forms, and they perform a huge variety of jobs within the body. Some are hormones that carry messages between cells, others are antibodies that fight illness. Some proteins store other nutrients for later use, while others make our skin stretchy and our tendons strong. Another type, called transport proteins , move substances around the body, including oxygen, fat cells, and even medications. Clearly, proteins are extremely important, but where do they come from? Protein is made up of amino acids, which are organic compounds of elements such as carbon and oxygen. There are 20 amino acids that the body uses in various combinations. Of these, 11 are called “nonessential,” which is a misleading term, because you do actually need them quite a lot! But these acids can be created by the human body—that is, they are nonessential in terms of your diet. The remaining 9 proteins are called “essential” because the human body can’t create them . . . and that’s where your diet comes in. The 9 essential amino acids need to be digested from food. The easiest way to get the protein you need is from sources such as beef, poultry, pork, and fish. The reason

Teen Guides to Health & Wellness: Diets, Cleanses, and Fitness

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