peptides are complex molecules that do all kinds of jobs in our bodies. They make up hair, nails and bones and help tissues and organs work the way they should. They’re the carriers that deliver vitamins, minerals and sugars through our blood streams. They help to power our muscles and support faster healing after injury. And they help carry oxygen into our cells, and even provide the light needed for photosynthesis (the process by which plants create energy).
The amino acids that make up proteins have a very specific structure. They’re linked together in chains that can twist into three-dimensional shapes. The sequence of amino acid ‘letters’ in a particular protein determines the protein’s mode of action, and is uniquely specific to each protein. Proteins are the building blocks of life, and they are found throughout nature. In fact, there are more than 100,000 kinds of proteins in the natural world. But the proteins that are essential for human health are those found in our muscles, immune system and digestive tract, which include antibodies and enzymes.
The quality of a protein is measured by its digestible indispensable amino acid score (DIAAS). This score indicates the number of amino acids in a protein that our body cannot synthesize and must obtain from the diet. The higher the DIAAS score, the better the protein. Animal proteins tend to have higher DIAAS scores than plant-based proteins. Healthy sources of protein include meat, fish, poultry, eggs, milk, cheese and legumes like lentils, beans (adzuki, black, fava, kidney, lima, pinto etc.), chickpeas/garbanzo, edamame/soybeans and peanuts.