What is protein used for in the body?
Protein is used to build and repair muscles, bones, skin, hair and organs. It also makes enzymes, hormones and antibodies, and can provide energy when needed.
Proteins are made of smaller units called amino acids, linked in long chains. The body uses 20 amino acids, nine of which are essential, meaning they must come from food. When we eat protein, digestion breaks it into amino acids, which the body reassembles into the specific proteins it needs.
Proteins do countless jobs. Hemoglobin carries oxygen in blood, enzymes speed up chemical reactions, antibodies fight infections and hormones like insulin carry messages. Collagen gives structure to skin and bones, and keratin forms hair and nails. Muscles are made mostly of protein.
How much do you need?
A common guideline for adults is about 0.8 grams of protein per kilogram of body weight a day, though needs are higher for athletes, older adults and during pregnancy. Good sources include meat, fish, eggs, dairy, beans, lentils, tofu, nuts and seeds. Most people in wealthy countries get enough.
Did You Know?
Animal proteins and soy contain all nine essential amino acids. Combining different plant foods, such as rice and beans, also provides them.
This answer is general information, not medical advice. For a personal health question, talk to a doctor.