Proteins are large organic molecules made of carbon, hydrogen, oxygen, nitrogen, and sometimes, sulfur. We can form from amino acids within the body or from amino acids within foods such as meat, dairy, fish, nuts, and beans.
We play important roles in all living things. Sadly, no one knew this until Linus Pauling discovered us in the 1950's. Some proteins, like my cousin Eryn, help cells keep their shape. My niece Lilli makes up muscle tissues, and my sister-in-law Ellie transports items in and out of cells.
Your eyes aren't strong enough to see us without a microscope, but if you could see us, we would look like this:
You may be thinking that since meat is a protein, you can eat lots of red meat, right?! WRONG. There are good AND bad types of protein. Protein can be used to help and harm your body!! According to the website hsph.harvard.edu, "...eating...red meat...on a regular basis is linked to an increased risk of heart disease and stroke, and the risk of dying from cardiovascular disease or any other cause." The website also states, "...eating healthy protein sources like fish, chicken, beans, or nuts in place of red meat...can lower the risk of several diseases and premature death."
Citation: https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/protein/