Proteins do many important jobs in the body, from making up hair, skin and nails to building muscle. They also help give us energy and make up the cells that form tissues and organs. Proteins can sense motion, light, taste and smell, and convey information to other parts of the body. They can even carry oxygen molecules in blood, as the hemoglobin protein does.

Protein is a complex molecule made of smaller components called amino acids, which are joined together in chains. The sequence of these amino acids determines a protein’s specific structure and function. Each amino acid has its own unique chemical properties, which is why we need to eat a wide variety of foods to get the protein we need.

The proteins we eat can be “complete” or “incomplete.” Complete proteins contain all of the twenty-plus amino acids that our bodies can’t make on their own. Examples of complete proteins are meats, dairy products and eggs. Incomplete proteins include beans (adzuki, black, fava, lima, pinto, kidney, garbanzo and others), peas (green, snow, split, edamame and soy products like tofu and tempeh), whole grains and nuts. People who eat plant-based foods can combine incomplete protein sources to get the essential amino acids they need.

The “amount” of protein we need varies, depending on age, gender, activity level and health goals. While more is not better when it comes to protein, research shows that getting adequate amounts of protein may help prevent weight gain, nutrient deficiencies and improve exercise performance. peptides