Protein is an essential nutrient for a variety of body functions, but there are a lot of misconceptions about protein on the internet. In this post, I (a Registered Dietitian) will address some of the biggest facts and myths about protein.
A quick recap: What is protein?
Protein is one of the three macronutrients. Macronutrients are nutrients that the body needs in relatively large amounts, therefore we should consume them daily. The three macronutrients are protein, carbohydrates and fat. Today we will be talking specifically about protein.
The macronutrient protein is used by the body for many, many functions. Just like adequate protein and fat, we need protein to keep us healthy. For more basic info about protein, you can read my introductory post here.
What does protein do?
There is not one specific function of protein in the human body. In fact, proteins are a part of each and every one of our cells. The body uses protein for growth and for the repair and maintenance of cells like the ones in our muscles, skin, hair and nails.
Our bodies also use protein to make enzymes and hormones, which are key for normal body functions (like digesting food) and every day health. Protein is also necessary for red blood cell production and tissue repair when you get something like a cut, burn or sore. Protein is no joke!
How much protein do you really need to eat?
There is a lot of misconception and debate around how much protein one really requires on a daily basis for health. So before we answer this, let’s define “health”.
The Oxford Dictionary definition of health is “the state of being free from illness or injury”. Meanwhile, the WHO definition of health is “a state of complete physical, mental, and social well-being, and not merely the absence of disease or infirmity”.
But let’s be frank. Health is a pretty subjective term. If often means something different to everyone.
In this post, we’re really referring to health as the absence of illness, injury, deficiencies, etc. Normal body functioning. In this post, health doesn’t necessarily mean the fittest you’ve ever been, toned, shredded or “jacked”.
With that said, generally, healthy adults need a minimum of 0.8 grams of protein per kilogram of body weight per day. This is in order to support and maintain health and normal body functioning. Keep in mind that this is a general recommendation. Nutrition is so highly individual, and how much protein you need does depend on your age, sex, height, weight, fitness/activity levels, medical history, and more. Depending on your goals and how active you are, you may need more.
If you’re looking to get a better idea of your protein needs, I recommend talking to a Registered Dietitian one on one!
How to Meet Your Protein Needs:
Despite protein always being such a hot topic in fitness and nutrition, it may be a surprise to you that most North Americans already meet their daily protein needs (cite). Protein is not typically the biggest nutrient of concern in generally healthy adults.
If, despite this data, you’re still unsure whether or not you’re meeting your protein requirements, here are some tips:
Aim for 15-20 grams of protein per meal and 5-10 grams of protein per snack. This does not have to be exact, some meals and snacks will have more and some will have less. In order to aim for 15-20 grams per meal, try making 1/4 of your plate protein sources at each meal. Remember, this is a general recommendation, not a hard and fast rule!
I don’t recommend weighing and counting all of your food every day, that’s no way to live! But if you feel you’re not getting enough of something, reading nutrition labels and figuring out the grams per serving can help you learn which foods and generally how much to incorporate. Oh, and speak to a Registered Dietitian!
Food sources of protein:
Protein can be found in both plant and animal foods. Canada’s Food Guide does recommend that we try to make more of our protein choices plant-based sources. Here’s a list of both.
Plant-based sources of protein:
Soy products like tofu, tempeh, soy beans (edamame), and soy milk.
Beans and legumes like lentils, chickpeas, split peas and more.
Nuts and seeds like peanuts, almonds, cashews, walnuts and their respective nut butters, quinoa, hemp seeds, pumpkin seeds, sunflower seeds and more.
Whole grain products like bread, pasta, buckwheat, bulgur and more.
Animal-based sources of protein:
Meat, fish, poultry, seafood and eggs.
Dairy products like yogurt, cheese, cottage cheese and milk.
Facts and Myths About Protein:
Now that we’ve covered the basics, let’s break down some facts vs. myths about protein.
Is animal protein better than plant-based protein?
One of the protein myths out there is that animal protein sources are better protein choices because they are more easily absorbed than plant-based protein sources. Let’s break it down.
The general quality of a protein is determined by its amino acid composition. Amino acids can be qualified as essential and non-essential. Essential amino acids (of which there are 9) are ones that the human body cannot create or produce on its own. Non-essential amino acids (the remaining 12) are ones that our bodies can produce.
Typically, a “quality” protein source contains higher levels – if not all – of the essential amino acids. Protein sources that provide all 21 amino acids, including the essential ones, are considered complete proteins. Animal proteins (see above) tend to be complete protein sources.
Meanwhile, many plant-based protein sources tend to be incomplete. They may lack one or more of the nine essential amino acids. However, there are a few plant-based protein sources that are complete, like quinoa and chia seeds.
Why you should consider more than protein quality:
Hold up – Before you go on believing that animal proteins are better than plants, you have to consider the package that the protein comes in. This is what is more likely to impact your health.
When we eat food sources of protein, we’re also eating the package that they come in. So when you consume animal protein, like a steak, you’re also consuming things like saturated fat and iron. If you eat a few slices of lunch meat or bacon, you’re also eating saturated fat and sodium.
On the other hand, when you eat lentils for protein, you’re also eating fibre and and no saturated fat and sodium. Salmon provides protein, as well as omega-3 fatty acids.
This isn’t to say that you should or shouldn’t eat animal or plant-based proteins. I wholeheartedly believe whatever foods you like can fit in your healthy lifestyle. What I’m trying to say is that there is more to consider than just whether or not a protein is complete or incomplete.
Besides, plant-based eaters can easily get all of the essential and non-essential amino acids by eating a variety of plant-based protein sources daily. My biggest tip? Always aim for variety. Whether you’re a meat-lover, vegan, vegetarian or flexitarian, it’s always beneficial to 1) eat a varied diet and 2) eat lots of plants .
Now, let’s address some myths about protein!
Do I need protein supplements?
Despite their popularity, most people don’t actually require expensive protein supplements (like protein powder) to meet their needs.
That being said, if you do find it hard to get enough protein from food, protein powder may be helpful. It may also be helpful for certain populations like athletes who have greater protein requirements. Also, if you genuinely enjoy using protein powder, I’m not here to stop you. I just don’t want anyone to feel pressure to spend money on powders they may not need.
Protein powders tend to either be dairy-based (whey or casein) or plant-based (like hemp, soy or pea). For the general population, choose whichever best fits your lifestyle but try to choose one that has minimal added ingredients like sweeteners and flavours.
If you’re curious about collagen protein supplements, you can read all about that in another blog post here.
Can we really only absorb 30 grams of protein at a time?
This is a big area of confusion and debate in the nutrition world. Let’s set the record straight.
First off, from a nutrition standpoint, the term “absorption” refers to the passing of nutrients from the gastrointestinal tract into the blood stream. Based on this definition, the amount of protein that can be absorbed is unlimited.
However, some evidence does suggest a maximum dose of 20-25 grams of protein for muscle protein synthesis (muscle-building) per meal may exist [2,3]. BUT, this doesn’t necessarily mean that any and all additional protein you consume will be wasted. Additional amino acid constituents can be broken down for energy or transformed to create alternative compounds used in additional bodily functions . Remember all of the roles that protein play we mentioned earlier?
Moral of the story: If you are trying to build muscle, just keep it in mind that consuming upwards of 40 grams of protein after a workout does not mean you’ll put on more muscle. Instead of loading up on extra protein after a workout, make sure you consistently eat adequate amounts throughout the day.
Is too much protein bad for your kidneys?
This is a bit of a myth, but too much protein may be bad for you. Here me out.
Too much of anything has to potential to be bad for us. Too much water, too many vitamins (hello, vitamin toxicity), too much sun exposure, etcetera. Of course, the same goes for protein. But the belief that eating a high protein diet (more than 1.5 grams per kilogram of body weight) is bad for your kidneys isn’t necessarily true.
Unless you have an underlying kidney condition like chronic kidney disease or history of kidney issues, you don’t really need to watch your protein intake as the evidence demonstrating a link between high protein intake and kidney damage is lacking . That said, if you are planning on implementing a high-protein diet, I recommend talking to your doctor or a registered dietitian before making changes.
The bottom line:
Weight loss and diet trends have really put the emphasis on protein lately. With that comes a lot of misconceptions and myths about protein. While adequate protein is important for good health and body functioning, it’s important to consume a balanced diet that provides a variety of macro and micronutrients. You should aim to eat a variety of protein sources throughout the day at meals and snacks.
Connect with Hannah Magee, RD!
What is your favourite source of protein? Are you an animal or plant-based protein fan? I would love to hear your thoughts on this post about facts and myths about protein in the comments below.
1. Tuso PJ, Ismail MH, Ha BP, Bartolotto C. Nutritional Update for Physicians: Plant-Based Diets. Perm J. 2013 Spring; 17(2): 61–66. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3662288/
2. Symons TB, Moore-Sheffield M, Wolfe RR, Paddon-Jones D. Moderating the portion size of a protein-rich meal improves anabolic efficiency in young and elderly. J Am Diet Assoc. 2009 Sep 1; 109(9): 1582-1586. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3197704/
3. Areta JL, Burke LM, Ross ML, Camera DM et al. Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis. J Physiol. 2013 May 1;591(9):2319-31. Available from: https://pubmed.ncbi.nlm.nih.gov/23459753/
4. Schoenfeld BJ & Aragon AA. How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution. J Int Soc Sports Nutr. 2018; 15: 10. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5828430/#CR1
5. Martin WF, Armstrong LE, Rodriguez NR. Dietary protein intake and renal function. Nutr Metab (Lond). 2005; 2:25. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1262767/