Proteins are a crucial, key component in almost every biological process in the body. Our genes serve as an instruction manual that guides the generation of proteins. But you might not know much about amino acids, the building blocks of proteins.

Units of amino acids called polypeptides allow your body to make the different proteins you need to function. The reverse is true as well. After you eat, proteins are broken back down into amino acids to help do many things, such as provide energy, produce hormones and build muscle.

Amino acids can be grouped into two categories: essential and nonessential. Both forms are important, but the difference is that while you can only get essential amino acids through your diet, your body can produce nonessential amino acids naturally. Eating proteins such as meat, eggs, dairy and some types of beans and grains can help you make sure you have enough of the nine essential amino acids. Each essential amino acid is associated with a different role in the body. Most people don’t need to worry about their levels of nonessential amino acids because your body will make as much as you need.

Amino acid-related disorders are those that affect metabolism. Phenylketonuria (PKU) is one of the better known examples of an amino acid disorder. People with PKU cannot metabolize the amino acid phenylalanine, which causes it to accumulate to unhealthy levels in the body. Too much phenylalanine can cause neurological damage, including seizures, in some people. People who have PKU need to avoid phenylalanine in their diet—which means eating very little protein—to prevent it from building up in the body.

You can get more amino acids in your diet through supplements. If you’re an athlete, your doctor or coach may suggest you take branched chain amino acid (BCAA) supplements. BCAAs help athletes produce muscle and decrease soreness associated with exercise. BCAAs also prevent muscle wasting—the breakdown of muscle during exercise that can also occur with certain illnesses.

Although it’s important to make sure you’re getting enough essential amino acids in your diet, don’t forget to talk to your medical care team before you make any major changes.