You probably know you need to eat protein, but what is it and where exactly do you find it? The answer is – everywhere – if you’re talking about the body. Proteins make up about 42% of the dry weight of our bodies. The protein collagen—which holds our skin, tendons, muscles, and bones together—makes up about a quarter of the body’s total protein. Protein builds, maintains, and replaces the tissues in your body. Your muscles, your organs, and your immune system are made up mostly of protein. All of our cells and even blood are packed with protein molecules.
Proteins, along with fats and carbohydrates, are the macronutrients that form the basis of our diets. Once consumed, some people associate protein only with helping to build muscle, but keep in mind that’s not all it does for us. In our bodies, protein performs a range of duties, from building new cells to regulating metabolism to helping cells communicate. Proteins help shuttle oxygen throughout the body in the form of hemoglobin, as well as build muscle.
When you eat foods that contain protein, the digestive juices in your stomach and intestine go to work. They break down the protein in food into basic units, called amino acids. The amino acids then can be reused to make the proteins your body needs to maintain muscles, bones, blood, and body organs.
Amino acids are the building blocks of proteins. Our DNA directs the body to join various combinations of amino acids into a variety of sequences and three-dimensional shapes for an arsenal of over 2 million different proteins, each serving a unique function. Our bodies can make some of these amino acids, but there are nine that are considered “essential amino acids” because we must consume these through our diet.
Many foods contain protein, but the best sources are:
- dairy products
- legumes like black beans and lentils
While our bodies can store fats and carbohydrates to draw on when needed, we do not have a storage pool of amino acids. We need a fresh source each day in order to build the body proteins we need. If the body is missing a particular amino acid to form the protein it needs, it will pull that amino acid by breaking down existing muscle protein. If we consistently lack certain amino acids we will lose muscle weight, energy and, eventually, fundamental functions.
The amount of protein you need depends on your weight and health. The Recommended Daily Allowance (RDA) for protein for the healthy individual is 0.8 grams of protein per kilogram of body weight or 3 to 4 grams per 10 pounds, and two to three servings of protein-rich food will meet the daily needs of most adults. Athlete’s protein intake recommendations may be higher.
The good news is that you don’t have to eat all the essential amino acids in every meal. As long as you have a variety of protein sources throughout the day, your body will grab what it needs from each meal.
You can look at a food label to find out how many protein grams are in a serving, but if you’re eating a balanced diet, you don’t need to keep track of it. It’s pretty easy to get enough protein.
*Dr. Shawn Tsuda is a General Surgeon specializing in robotic bariatric surgery. Schedule a consultation to learn more.