By Stephen Sheehan
Reviewed by Emily Gonzalez, ND for Scientific Accuracy

Article at a Glance:

  • A complete protein source contains all nine essential amino acids, all of which you can access by adding Bulletproof Complete Daily Energy Collagen Protein to your stack. This brand-new, keto-friendly supplement contains the eight essential amino acids found in collagen, plus added tryptophan, and can be easily mixed into a shake or nutritious smoothie.
  • While animal products provide your body with the building blocks it needs, those who follow a vegan diet need sources of complete proteins, too. You can access these nutrients in certain plant foods.
  • Incomplete protein sources are also important to your well-being, and can provide skin, hair, nail and joint support.

What is a complete protein, exactly? Most people immediately think of chicken breast, steak, protein shakes, or maybe even eggs. While these are all common protein sources consumed by everyone—from work-from-home parents to active bodybuilders—there are so many other ways to obtain this critical macronutrient.

Still, one fact remains: Not all proteins are created equal.

Although animal products like those mentioned above contain all nine essential amino acids, nuts (including almonds and cashews) and seeds (like sunflower and pumpkin seeds) do not. As a result, they cannot be categorized as complete protein examples.

The concept of complete protein isn’t just a trendy term thrown around the health and fitness community. Your body actually needs essential amino acids in complete protein sources in order to grow and repair tissue.

If your new year, new you goal includes unleashing your limitless potential, it’s time to get to know more about complete protein sources and how they can support your wellness goals.

Spoiler alert: we’ve got a new complete protein supplement with your name on it…


Amino acids are the building blocks that combine to form a protein. In total, there are 20 different amino acids that fall into three groups, including:

  1. Essential amino acids: Such as histidine, isoleucine, lysine and tryptophan.
  2. Non-essential amino acids: Like alanine, asparagine and serine.
  3. Conditional amino acids: Think arginine, glutamine and proline.

However, while our bodies produce 11 non-essential and conditional amino acids naturally, we cannot create the nine essential amino acids.

The ideal way to make sure you get these critical building blocks of protein is by eating foods that contain all of these essential amino acids. In other words: a complete protein source.

Consuming certain foods and specific supplements that contains all nine essential amino acids brings important benefits, too.

For example, valine plays a critical role in stimulating muscle growth and regeneration. Additionally, you need leucine to help regulate blood sugar levels and produce growth hormones. In addition, your skin and connective tissue depend on the presence of threonine, another essential amino acid found in complete protein sources.


However, contrary to popular belief, you can access essential amino acids without heating up your oven or grill! Enter: Complete Daily Energy Collagen Protein. This new offering not only provides a complete profile of essential amino acids (thanks, tryptophan!), but also contains the nutrients you need to charge your battery for sustained, everyday energy. Plus, a single serving contains 20g of collagen protein and 0g sugar*—calling all new keto dieters!

*Not a low-calorie food.

That makes it a perfect, seamless mix-in for your morning smoothie or shake, which can come in handy if you don’t have the time to cook or the appetite to eat a big breakfast!


Remember when we said not all proteins are created equal? Depending on the amino acid profile, some foods will fall into the “complete protein” category. Others will inherently fall short.

When it comes to complete protein examples, the most popular types are animal products. Meat, poultry, fish and eggs contain all nine essential amino acids. (If you’re a meat-eater, give this Slow-Cooked Lamb Barbacoa recipe a try!)

Dairy products also fall into the complete protein source category. If your body tolerates dairy, this means milk and cheese hit the mark. (While grass-fed ghee and butter do not, they are still quality fats to incorporate into your diet.)

For those following a vegan diet, complete plant proteins, like quinoa, are critical. You can feed your body the essential amino acids it needs via lentils (and other legumes, like peanut butter), but they must be paired with whole grains in order to form complete proteins. Vegans can also nourish their bodies with hummus made of protein-rich chickpeas. And, while soy products (like edamame and tempeh) are technically complete proteins, keep in mind that soy, along with beans and legumes, are not considered Bulletproof Diet-friendly.

Pro tip: If you’re aiming for a way of eating that is plant-driven but free of gluten, grains, soy and legumes, consider vegetarian keto. This diet factors in the principles of quality fats, complete proteins, minimal carbohydrates, and of course, plenty of veggies.


As you just learned, there are various ways to get your complete protein sources. However, if you’re following a specific diet, many of the above will not be suitable.

For example, keto vegetarians have to rely on non-animal protein sources while still incorporating quality fats into their diet. On the other hand, paleo eaters can’t consume soy or legumes, which removes additional routes toward getting all nine essential amino acids.

Here’s a list of complete proteins broken down into a few popular diets:

  • Keto/low-carb diet: Complete Daily Energy Collagen Protein, grass-fed beef, sustainable seafood, pasture-raised poultry and pork provide the building blocks of protein and quality fats.
  • Paleo: Stick to complete protein sources from animals, along with bee pollen and sea vegetables.
  • Lacto-ovo vegetarian: If your body does well with dairy, whey protein and cheese can be beneficial protein choices. Pastured eggs also pack a protein punch for vegetarians who don’t restrict their food choices quite so much.
  • Plant-based: Hemp seeds/protein powder, chia seeds and nutritional yeast all work well for plant-based dieters looking for complete protein foods.

The overarching point here is that no matter what dietary restrictions you may have, there are still plenty of complete protein sources you can—and should—eat.


What is a complete protein’s role in the body, and why are essential amino acids labeled as essential?

Your body needs enough protein for a variety of reasons. This vital macronutrient helps with the formation of muscle, as well as the transportation of nutrients. And, anyone who has attempted to bulk their biceps before can attest to the fact that protein is also essential in building and repairing tissue.

While it’s important to get your protein in, the amount you should consume daily varies on an individual basis. However, you can find your ideal protein intake by factoring in your body composition goal. For example, if you want to maintain the number on the scale, a good starting point is 0.4g of protein per pound of bodyweight. You may up that ratio to 1g per pound if you want to speed up recovery or burn fat.

On the other hand, one thing to remember is that deficiencies in any particular essential amino acid will disrupt key processes. Low-protein protein diets can result in descreased lean body mass and less satiation. Furthermore, protein is the most effective macronutrient that provides a satiating effect. Needless to say, it’s crucial to add complete proteins into your diet so your body can operate at peak efficiency.

If you are having trouble getting enough protein to keep your body thriving, talk to your dietitian or seek out medical advice.


Don’t let the term “incomplete protein sources” scare you off. Just because a particular protein source doesn’t contain the nine essential amino acids doesn’t mean it can’t support your body and overall health.

Actually, incomplete protein sources, or let’s call them complementary proteins, can be useful in supporting other health and wellness goals. Specifically, collagen protein products shine when it comes to making your skin, hair and nails look their best.

And the internal stuff matters, too! Collagen protein supports the bones, joints and muscles.

There are plenty of ways to add grams of protein from collagen-based products to your diet in order to meet your specific macro goals. For instance, stock your pantry with:

  • Bulletproof Collagen Protein: For cooking, stick to the unflavored varietal. There’s also chocolate and vanilla options that mix in easily with smoothies and can offer added benefits to your favorite baked goods. (If you’re in a hurry, make sure to have single-serving Bulletproof Collagen Protein GoPacks on hand!)
  • Bulletproof Collagen Protein Boosts: Looking for collagen protein options that bring even more health benefits? Bulletproof Collagen Protein Beauty Boost supports healthy hair, skin and nails, thanks to standout ingredients like grass-fed collagen protein, keratin, hyaluronic acid and vitamins like biotin, zinc and copper. Additionally, take care of your digestive system with Bulletproof Collagen Protein Gut Health. This supplement contains beneficial probiotics and prebiotics, zinc carnosine, L-Glycine and more, and dissolves easily into any drink. And, don’t forget about your body’s foundation. Bulletproof Collagen Protein Joint Boost supports joint strength and flexibility through the combination of collagen, glucosamine, chondroitin sulfate, Boswellia and other supportive ingredients.
  • Bulletproof Collagelatin: This collagen-gelatin combo is perfect for mixing into soups as a thickening agent that also supports healthy skin, joints and bones! You can also use gelatin made from collagen to whip up a bowl of Dark Chocolate Collagen Pudding or a batch of High-Protein Green Gummies for a sweet, nutritious treat.
  • Bulletproof Collagen Protein Bars: Perfect for a post-workout replenishment or a convenient protein snack on the go, you’ll definitely want to sink your teeth into a delicious collagen protein bar, from Lemon Cookie to Mint Chocolate Chip! As an added bonus, try a sinful (but guilt-free) Bulletproof Coconut Chocolate Dipped Collagen Protein Bar.
  • Bulletproof Cold Brew Latte: If you’re a cold brew lover, snag a case of ready-to-drink Cold Brew Latte cans. Delicious and nutritious, these flavorful sips also provide your body with a seamless serving of collagen protein, along with quality fat from MCT oil.

The bottom line: A complete protein contains all nine essential amino acids, which are the key building blocks your body needs to not only survive but thrive. There are plenty of ways to incorporate complete protein foods into your diet, even when restrictions exist. (Remember, though, incomplete proteins have a place in your life, too.) Invite Bulletproof collagen protein products into your daily diet so you can #BETHEPROOF and live nothing less than your best life!

Want to learn more about collagen? Check out this in-depth guide, which includes collagen-rich foods to eat, along with information on this protein’s many benefits.