Protein: A Complete Guide
Here is everything that you need to know about protein.
Whether your goal is to lose weight, gain muscle, recover from a tough workout or simply eat a little healthier, protein is an essential nutrient in any healthy diet. Not only is protein the building block for your muscles, organs and hormones, but protein also has many essential functions in the human body. So, here is your complete guide to protein and everything that you need to know about what protein is, the benefits of protein, the different types of protein, when to eat it and how much.
What is Protein?
Protein is one of three essential dietary macronutrients, along with carbohydrates and fat, and is a molecule made from chemicals called amino acids. Protein is considered a “macro” nutrient because it is required in significant amounts, as compared to “micro” nutrients such as vitamins and minerals which are required in relatively smaller amounts. The amino acids that make up protein molecules are responsible for various functions in the body; they carry oxygen through our blood, boost our immune system and help to build muscle. In total, there are 20 different amino acids required by the body, nine of which the human body can’t produce and therefore they must be consumed through our diet. Every 1 gram of dietary protein consumed provides 4 calories of energy to the body.
Why Do We Need Protein?
Although most people are aware that protein helps to build muscle it has many other vital functions. The amino acids found in protein help to produce important molecules in our body including enzymes, hormones, neurotransmitters, and antibodies. Protein is essential to our immune system, helping us build strong antibodies and fight off infection; protein helps replace worn-out cells, transports various substances throughout the body, and aids in growth and repair; protein is essential for the building and repair of our tissues and managing body weight; and of the three macronutrients, protein is actually the most satiating and satisfying, keeping us fuelled and full the longest.
What are the Benefits of Protein?
In addition to being an essential nutrient for the body, high-protein diets have been shown to support weight loss, increase muscle mass and strength, curb hunger, speed up recovery after exercise, and help individuals maintain a healthy weight.
What Foods Contain Protein?
Both animal and plant foods contain protein, however, animal foods are the most concentrated forms of dietary protein and include meat, organ meat and animal by-products such as eggs and dairy.
Animal Protein Sources
- Red Meat: Beef, pork, bison, lamb, game, etc.
- Poultry: Chicken, duck, turkey, etc.
- Fish: Salmon, tuna, mackerel, etc.
- Shellfish: Mussels, shrimp, scallops, etc.
- Plain Yogurt
- Cottage Cheese
In addition to animal sources of protein, there are some plant-based foods that contain higher concentrations of protein. Although not solely protein sources, as most also contain high levels of carbohydrates and/or fat, here are some of the top sources of vegetarian protein.
Vegetarian Protein Sources
Animal Protein vs. Plant Protein: What’s the Difference?
The primary difference between animal protein and plant protein in their composition of macronutrients and amino acids.
Animal proteins are concentrated sources of protein, with some fat and minimal carbohydrates, while plant proteins typically contain moderate levels of protein with some fat and higher levels of carbohydrates. In total, there are 20 amino acids that the human body uses to build proteins, and these amino acids are classified as either essential or non-essential. Your body can produce non-essential amino acids, however, it cannot produce essential amino acids, which therefore need to be obtained through the diet. For optimal health, the body requires all of the essential amino acids in the optimal ratios. Animal protein sources, such as meat, fish, poultry, eggs and dairy are considered to be complete sources of protein because they contain all of the essential amino acids that your body needs to function effectively, while plant protein sources, such as beans, lentils and nuts, are considered to be incomplete sources of protein as they lack one or more of the essential amino acids that the body needs. Although soy products (such as tofu or tempeh) are very close to being complete proteins, two essential amino acids are only found in small amounts in soy and therefore they are not completely comparable to animal protein sources.
This is not to say that you can not or should not consume plant-based protein, however, should you choose to only consume plant-based protein and avoid animal protein, it is imperative that you consider how you are combining your plant-based protein sources for optional macronutrient and amino acid ratios. Given plant-based proteins do lack one or more amino acids, it can be more difficult to get all the amino acids that your body needs including essential vitamins and minerals that come along with it. Therefore, it is suggested that individuals who consume solely plant-based protein monitor their intake of vitamin B12, vitamin D, DHA, iron and zinc to ensure that they are consuming sufficient amounts for optimal health.
So, Can you Get Protein from Plants?
Yes, certain plant foods do contain protein, such as beans, lentils, nuts and seeds to contain amino acids, however, they are considered incomplete sources of protein. Plant-based sources of protein do not contain all of the essential amino acids or do not contain them in optimal ratios and, therefore, it is imperative that individuals following a plant-based diet or vegetarian diet consume a wide variety of plant-based proteins to ensure that they are consuming all of the essential dietary amino acids.
How Much Protein Do I Need?
Most official nutrition organizations recommend a fairly modest protein intake. In the last couple of years, Health Canada has removed the recommended daily value of protein suggesting that “most people get enough protein” and now suggest that people “chose a variety of protein foods” as part of a healthy diet. Unfortunately, the term “most people” is very broad and it suggests that some people are still not consuming enough. Prior to this change, the recommended daily value for protein was 0.8 grams per kilogram (or 0.36 grams per pound) of body weight per day and, therefore, it would be recommended that a 150-pound person consume, at minimum, 54 grams of protein per day.
As a general rule, this formula is a great place to start. With a few simple calculations, you can quickly determine if you are in the right ballpark of protein intake, and although some people will certainly be consuming enough protein, others may discover they are falling short. For example, someone eating a standard North American diet of a bagel for breakfast, a sandwich for lunch and a bowl of pasta for dinner will likely not meet their recommended intake. It is also important to keep in mind that this recommendation is based solely on the amount to avoid protein deficiency or malnutrition; it does not necessarily reflect an ideal intake. Depending on the specific individual and their goals, there are certain situations where it may be advantageous to increase protein intake.
High Protein Foods
Although there are truly too many foods to list, here are some of the most popular high-protein foods and the amount of protein they provide per serving:
- Steak: 24 grams per 3oz serving
- Lamb: 24 grams per 3oz serving
- Pork Loin: 23 grams per 3oz serving
- Bison: 22 grams per 3oz serving
- Ground Beef: 17 grams per 3oz serving
- Chicken Breast: 27 grams per 3oz serving
- Duck: 20 grams per 3oz serving
- Chicken Thigh: 19 grams per 3oz serving
- Eggs: 12 grams per 2 eggs
- Tuna: 25 grams per 3oz serving
- Octopus: 25 grams per 3oz serving
- Salmon: 21 grams per 3oz serving
- Sardines: 20 grams per 3oz serving
- Shrimp: 19 grams per 3oz serving
- Halibut: 19 grams per 3oz serving
- Anchovies: 17 grams per 3oz serving
- Scallops: 18 grams per 3oz serving
- Mussels: 18 grams per 3oz serving
- Cottage Cheese: 23 grams per 1 cup serving
- Greek Yogurt: 21 grams per 1 cup serving
- Plain Yogurt: 9 grams per 1 cup serving
- Cheddar Cheese: 6 grams per 1 oz serving
- 2% Milk: 8 grams per 1 cup serving
- Tempeh: 17 grams per 3oz serving
- Tofu: 15 grams per 3oz serving
- Edamame: 18 grams per 1 cup serving
- Lentils: 18 grams per 1 cup serving
- Black Beans: 16 grams per 1 cup serving
- Chickpeas: 14 grams per 1 cup serving
- Teff: 10 grams per 1 cup serving
- Quinoa: 8 grams per 1 cup serving
- Brown Rice: 6 grams per 1 cup serving
- Millet: 6 grams per 1 cup serving
- Buckwheat: 6 grams per 1 cup serving
NUTS & SEEDS
- Peanuts: 7 grams per 1oz serving
- Almonds: 6 grams per 1oz serving
- Pistachios: 6 grams per 1oz serving
- Hemp Seeds: 9 grams per 1oz serving
- Sunflower Seeds: 6 grams per 1oz serving
- Flax Seeds: 5 grams per 1oz serving
- Chia Seeds: 5 grams per 1oz serving
- Sesame Seeds: 5 grams per 1oz serving
Please note that all values are based on cooked values and data provided by MyFoodData.
When Should You Eat Protein?
Protein timing can vary from one individual to another based on their individual goals and needs. For individuals who are looking to build muscle, some research shows that consuming protein post-workout can help to build muscle and support recovery, however, there is limited evidence regarding the best time to eat protein for weight loss, rather, ensuring that you are within your caloric range and consuming protein within this range has proven to be beneficial. For general health, ensuring that you are consuming an adequate amount of protein throughout the day is more important than when exactly you consuming it. By spreading out your protein intake throughout the day and enjoying a serving of protein at every meal you can help to ensure that you are reaching your required protein intake.
Who Needs more Protein?
Depending on the specific individual and their goals, there are certain situations where it is advantageous to increase protein intake, at least temporarily.
- Athletes or Individuals who Train Hard: For people who are very active and/or trying to build or maintain muscle mass it is recommended to consume between 1.2 to 2 grams of protein per kilogram of body weight to help optimize recovery from training and maintain optimal body composition and athletic performance.
- Individuals Trying to Lose Weight: Compared to carbohydrates and fat, protein is the most satiating macronutrient and can help to balance blood sugar keeping us full for longer periods of time. Therefore, not only can consuming additional protein help to manage hunger cues, but it can help to increase metabolic rate by supporting the growth and maintenance of muscle mass, especially when paired with resistance training, which is essential for weight loss.
- Older Individuals: As we age, our bodies tend to experience a loss of muscle mass, also known as sarcopenia, which can have many devastating consequences so ensuring we consume adequate protein is vital. In fact, loss of muscle mass can put older adults at a higher risk of injury, pain and a general inability to perform daily activities and, therefore, consuming a higher protein diet can help to prevent further tissue breakdown and reduce the adverse effects of ageing.
- Individuals with Blood Sugar Disruption: Protein does not impact blood sugar the same way carbohydrates do, especially refined carbohydrates. High-protein diets have been shown to have a stabilizing effect on blood sugar, and lead to beneficial changes in a wide range of metabolic, cardiovascular and inflammatory markers.
Do You Need a Protein Supplement?
Generally speaking, individuals should be able to get enough protein from their diet alone. In fact, you can easily consume adequate enough dietary protein through whole foods by consuming a source of animal or plant-based protein at every meal or regularly throughout the day. With that said, there are certain individuals who may find supplementation beneficial or convenient for certain situations or periods of time, however, protein supplements should always be considered exactly that – supplements. Protein powders, protein shakes and protein bars should be used as a supplement to a healthy diet of whole food sources of protein, not a replacement for them.
How Much Protein is Too Much?
Although protein is essential for life, even too much of a good thing can be a bad thing. Although the exact amount varies from person to person, excess levels of protein have been linked to cardiovascular disease, kidney stones, and digestive issues. However, keep in mind these are only associations; meaning some studies have noted these conditions among people on high protein diets, but that doesn’t mean the protein was the direct cause of the condition.
How Do I Eat More Protein?
No matter how much protein you need or what your goals are, here are some simple tips to help you make the most of your protein intake:
- Eat a Source of Protein at Every Meal: Consuming a source of animal or plant-based protein at every meal will help to ensure that you are reaching your required protein intake while promoting fullness and satiety.
- Eat Your Protein First: Consuming your protein first, or earlier in your meal, will ensure that you do not fill up before you get to your protein, and some research suggests that eating your protein first can help to balance your blood sugar for longer periods throughout the day.
- Consume a Wide Variety of Protein Sources: Eating a wide variety of protein sources, both animal and plant-based, throughout your meals can help to ensure that you are not only consuming adequate protein but that you are consuming a wide variety of nutrients in the process.
- Consume Protein After Your Workout: Consuming protein after a workout gives your body the amino acids needed to repair the proteins that were broken down during exercise. The rate of these breakdowns depends on the type and intensity of the activity, but eating protein post-workout helps to repair and rebuild the muscle proteins to help build muscle, which can support weight loss.
- Snack on Protein: Most snack foods available today are high in refined carbohydrates and sugar, which will leave you hungry and unsatisfied, however, consuming protein at snack time can help to promote fullness and ensure that you are reaching your required daily protein intake.
The Bottom Line
Protein is an essential macronutrient and, regardless of a person’s goals, should be consumed regularly for optimal health. By consuming protein at every meal and eating a wide variety of protein sources, both animal and plant-based, you can help to ensure that you are consuming adequate protein. For specific individuals in specific situations, it may be beneficial to consume additional protein to support their health goals and this can be done through whole foods or a high-quality protein supplement.