You would have a hard time finding people who think that protein is “bad.” Other than people managing kidney disease, and folks committed to a deep-keto diet, we have few worries about getting “too much” protein when following a wide variety of eating plans. How did protein escape the macronutrient blame game that has plagued fat and carbs, and why is its reputation so good?
Let’s first consider protein as fuel. One gram of protein provides four calories to the body, just as one gram of carbohydrate does. But judging protein by its fuel value is like evaluating the 2x4’s inside the walls of your house as firewood. If we are burning protein for energy, something has gone terribly wrong! Protein is far more valuable to us as a raw building material for our body structures.
Of course, protein is most famous as the main component of muscle tissue; we can’t get those big flexy biceps and killer quads without plenty of protein. But protein is a fantastic structural molecule, and it has more to do with building our beach-ready body than just getting flexy with it. Calcium gets all the credit, but bone is approximately 50% protein by volume! Protein is a fabulously flexible building substrate, and makes up many of our hormones and neurotransmitters. Connective tissues, including joint tissue, tendons/ligaments, arteries, and skin, are made of glycoproteins (proteins fused with carbohydrates - more on that when we dive into carbs!). And our hair and nails are made largely of protein. That’s a lot! That means that not only does protein “make us strong,” it literally gives our body structure, helps our body maintain strong internal communications, holds it all together, and makes us look pretty on the outside.
An important thing to realize about protein, is that we don’t have “storage” for it the way we do for fat - all the protein in your body is already doing something important. So, if you don’t eat enough, your body has to rob the less important structures (say your muscles) for survival-essential tasks (build hormones). Also, while we can burn protein for energy the same way we can use fat and carbs, and in fact our body can turn extra protein into fat or carbs, we can’t do the reverse and turn other macros into protein. That means that we need to be sure to get enough from our diet.
So how much protein do we need to eat to ensure that all these functions are fulfilled for optimal health and performance, and is it possible to eat too much? It’s possible to eat too much protein, but it’s pretty rare. Our bodies are very good at regulating protein consumption - there comes a point where you just can’t look at another chicken breast or steak. We are also capable of converting excess protein to energy. Protein toxicity is generally only seen in cases where lean protein is pretty much the only food source. Individuals with kidney disease should be cautious about not overconsuming protein, because their limited kidney function could be overwhelmed by the byproducts of metabolizing the excess. People following a ketogenic diet will also restrict their protein intake to the lower end of the spectrum, to avoid metabolizing excess protein into unwanted carbohydrates.
So how about the rest of us - how much protein should we be eating? Well, it depends (you’ll hear this answer from me a lot). The spectrum of healthy protein consumption starts around ⅓ gram of protein per pound of bodyweight - that means at least 50g/day for a 150lb person without big protein demands on their body. The more active you are, the more protein you’ll need, especially if you are pursuing strength gains. One gram per pound of bodyweight would be a reasonable goal for an active person. As we age, protein absorption becomes less efficient, so older folks will want to prioritize protein consumption. People pursuing weight loss would also want to increase their protein consumption, to protect their muscle while losing fat.
What happens if we don’t eat enough protein for our needs? Our bodies will engage in nutrient triage, and partition the protein we consume to the most important purposes to keep us alive - always appreciated, but it may not help us meet our goals. Every time we workout, we cause tiny tears in our muscles, bones, and connective tissue. It’s the repair of these tiny tears that ultimately makes us stronger and our bones denser, but if there is not sufficient protein to repair them before our next workout, we risk accumulating too much damage and suffering an injury (we’ll revisit this concept when we get to carbohydrates as well). Without enough protein, we may not produce enough hormones and neurotransmitters, especially those regulating mood and sleep. Lowest on the triage list will be our hair and nails, so if your hair and nails are growing slowly, or just “kinda funny looking,” take a look at your protein consumption!
OK, you’re convinced now, protein is awesome! Where do I get it?! Folks who enjoy animal-based foods will have plenty of options for protein-rich foods. Meat, fish, eggs, and dairy are all sources of complete protein, as well as varying amounts of fats and plenty of micronutrients. Those who prefer a plant-based diet will have to be more attentive to protein consumption, because plant foods are generally not as protein-dense as animal foods. Plant-based eaters will also want to be sure that they are consuming a complete protein source, containing all essential amino acids. Quinoa and buckwheat are plant-based sources of complete protein, and combining foods (usually a grain and a legume) is a good strategy for getting a complete protein. Rice and beans is a staple in some cultures, and oats with peanuts is another popular combination. Usually, eating a wide variety of protein sources will cover your bases on the protein front, and ensure a rich selection of micronutrients as well.
Now that we’ve established that protein deserves its shining reputation, stay tuned to tackle the macro “bad boys” fat and carbs!