By: Shivani Shah
Certain sights, sounds, and smells flood my memory when thinking of elementary school. This includes Elmer’s glue, field day, school supply lists, and the Scholastic book fair. A less fondly remembered but equally as potent memory is the colorful triangular diagram that was the food pyramid. These distinct images of milk cartons, broccoli, and eggs could be found on posters hanging in the gym and the cafeteria. This infographic ingrained into my young mind (and perhaps yours) that grains should be the largest portion of our diet while fats should be consumed most sparingly. We know today that these recommendations were, simply put, flawed. When talking about dietary guidelines, carbohydrates and fats have long been at the forefront of conversation, but what about protein?
Protein is a macronutrient that serves as a building block for many of our bodily functions. It is found in virtually every tissue and is critical in regulating the structure, function, and regulation of bodily processes. Proteins are made from structural units called amino acids. There are 20 amino acids. 9 of these amino acids are essential, meaning, they must come from your diet because the body cannot make them. Proteins are the building blocks of muscle. Skeletal muscle is the largest organ in the body. When thinking about muscle, we often think about its locomotive functions in helping us move, breathe, and maintain posture. In addition to these locomotive functions, skeletal muscle also serves as a critical part of our metabolic health. And, more recently, evidence shows that skeletal muscle also serves as an endocrine organ. In response to exercise, skeletal muscle has been shown to secrete molecules classified as “myokines”. Certain myokines have already been shown to exert anti-inflammatory effects. Inflammation has been shown to be a root cause of many chronic diseases, so this emerging field of research surrounding myokines is very exciting as we discover more about muscle-organ crosstalk. From insulin regulation to how we age, skeletal muscle is essential for many processes. In addition to exercise, dietary protein intake is one of the most important factors to determine muscle building and retention.
The RDA, or recommended daily allowance, of protein is .8 grams per kilogram of bodyweight per day. The key point here is that the minimum amount of protein required to prevent illness, not to promote health. Aging is correlated with a natural loss in muscle mass - which is then linked to several chronic illnesses, including diabetes, stroke, sarcopenia, and osteoporosis. Therefore, it is particularly important to eat more protein as we age.
As a lifelong vegetarian, I’ve always been asked, “But how do you get your protein?”. In general, animal proteins are considered “complete proteins”, in that they contain all the essential amino acids. On the other hand, plant proteins are often, but not always, incomplete sources of protein; however, research shows that eating a diverse array of plant foods can get you all the essential amino acids. If you are plant-based, it may be tricky to get all the essential amino acids. In this case, and especially if you work out, taking branches chain amino acids (BCAAs) may be a good idea. BCAAs are three essential amino acids that are critical in muscle development and maintenance. Of these three BCAAs, leucine is particularly noteworthy as it alone has shown to act as a stimulatory signal for muscle protein synthesis.
In recent years, protein has become a hotly debated topic. There are many conversations around plant versus animal protein, sustainability, food insecurity, and more. These are important conversations that need to take place and will likely take years of scientific research and societal discourse to truly reach any sort of consensus. I hope the information in this article encourages you to approach your diet with a new perspective. As always, consult a medical professional before making any changes to your diet or lifestyle.
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