Plant Protein vs. Animal Protein: What's the Difference?

Does it really make a difference if you get your protein from animals or plants? More and more people are opting for plant-based alternatives. Whether it’s replacing a traditional beef burger for black beans, or sausage for plant-based salami, eating more plant-based foods can have benefits on overall health and wellness. But, just like so many things in life, it’s just not that simple. If you’re not following a plant-based diet, choosing a kale salad over a juicy and tender filet just doesn’t really make sense, does it? We’re going to explore the differences between plant protein vs. animal protein so you can decide which one will provide more benefit for you and your lifestyle.

On a very basic level, protein, animal or plant, is much the same. Protein is made of amino acids and plays a critical role in the development of muscle mass and tissue. Often times you’ll read claims that protein powder can help build muscle and improve exercise recovery. That’s because protein repairs and builds human cells through a process called muscle protein synthesis. There are 20 essential and non-essential amino acids, which are responsible for various bodily functions. This leads us to our first difference between animal vs. plant proteins – incomplete and complete proteins.

Incomplete vs. Complete Proteins

One of the biggest arguments when it comes to choosing animal or plant protein is the incomplete vs. complete debate. Of the 20 amino acids, 9 of them are essential meaning your body cannot produce them on its own, so it’s crucial to get them from the food you eat or through supplementation.

All animal proteins are complete sources of protein and contain adequate levels of each amino acid to produce important biological functions. When a protein is lacking in one or more of any certain essential amino acid, it’s labeled as an incomplete protein.

Therefore, in terms of proper nutriment, it’s easier to get all essential amino acids from animal protein. Essential amino acids, such as leucine, isoleucine, and valine are all essential for building more muscle mass and optimal muscle recovery post-workout. Thus, if you choose a plant-based lifestyle, it is critical to choose plant-protein sources that are complete proteins or combine them to create complementary proteins.

Related: Ultimate Guide To Vegan And Vegetarian Protein Sources

Protein Content & Density

Ever heard the phrase, “Stronger pound for pound?” Well in terms of protein content, “pound for pound” animal protein has more protein content than plants, per oz. On average, a 4 oz cut of lean animal protein, (chicken, pork, fish, beef) will provide roughly 20-25g of protein. Tofu, which is one of the most protein-dense sources of plant protein, provides 10g per 4oz. That means, in order to get the same amount of protein in your diet, on average you need to eat 2-3 times the amount of plant-based food than animal-based to get the same amount of protein. Pound for pound, animal protein is more protein-rich. The analogy comes to life.

How much protein each type of source offers is a big deal when you’re trying to build more muscle and hit your macronutrient goals. Animal proteins offer a great concentration of protein per serving, almost always.

Digestion Rate 

Another factor to consider, is how much of that protein actually gets used to build and repair your muscle mass?  Research does show that animal proteins have a slight edge when it comes to digestion rate and the ability to stimulate muscle protein synthesis. More amino acids are used when your protein comes from animal sources.

But what do the studies show in terms of performance outcomes? Pea protein, which is a popular source of plant-based protein used in protein powders has a comparable amino acid profile to whey, aka animal protein. Dubbed the powerful green bean, peas are packed with protein and considered a complete source, containing adequate levels of all 9 essential amino acids.

A head-to-head study published in the Journal Of The International Society Of Sports Nutrition investigated the effects of pea protein vs. whey on muscle composition and strength. The results showed a significant and greater effect on muscle composition amongst the pea protein group, with no clinical difference between groups in regard to muscle strength.¹

A pilot study conducted at Lipscomb University in Tennessee compared the effects of whey and pea protein supplementation in conjunction with 8-weeks of High-Intensity Functional Training (HIFT) on strength, body composition, muscle thickness, peak force, and WOD performance.

The results confirmed that whey and pea proteins promote similar strength, performance, body composition, and muscular adaptations following 8-weeks of HIFT.²

The thing to remember, is that these are just two examples, using one type of plant protein. Although the results do show that pea protein can provide similar results to animal protein when used as an ergogenic aid, purely drinking pea protein to hit your macronutrient goals, will be a challenging and unpleasant experience. The fact that there’s also a massive body of evidence that shows animal protein edges out plant protein when it comes to protein synthesis does play a defining role as well. The bottom line is that more research needs to be done to provide substantial evidence to know whether plant proteins are as good as animal proteins when it comes to improving athletic performance and strength.

Related: Complete A-Z Guide for All Types of Whey Supplements

Micronutrient Profile

Now, to discuss a distinct differentiation factor – micronutrients. The real question is, what else are we getting with each source of protein? Animal protein for example, is a rich source of Vitamin D and Vitamin B12. Often times plant-based foods are fortified with these micronutrients. Supplementation is key, especially when you’re following a plant-based diet, to ensure adequate amounts of B12 and Vitamin D.

That being said, plant proteins have a litany of differing vitamins and minerals that animal protein doesn’t offer. But, that depends on the exact source of plant protein you’re consuming. For example, one of the biggest advantages plants provide, is fiber. Beans and vegetables have a high fiber and protein content, meaning you can build muscle and be regular. Plants also contain bioactive compounds or phytonutrients called flavanols, which help reduce free radical damage often associated with chronic disease and inflammation. Most plant protein sources are also rich in potassium, magnesium, zinc, and copper.

Animal protein doesn’t contain carbs, which means that with plant protein sources you’re going to get some carbohydrates. If your goal however is to cut body fat, build lean muscle mass, or gain more strength, including key complex carbohydrates and fiber from starchy vegetables is a must to optimize your athletic goals. Nevertheless, if you’re goal is reduce carbohydrate intake, you best bet, is opting for animal protein and supplementing with whey protein isolate or hydrolysate. 

In terms of fat content, almost all animal protein sources contain saturated fat, yet the quantity widely varies. A filet is not going to have the same fat content, then let’s say a rib-eye. Different cuts of meat will have different amounts of fat, just like ground animal proteins will have different fat to protein ratios in animal sources such as chicken, turkey, beef, and bison.

What Type Of Protein Powder Should I Use?

When it comes to what type of protein powder you should use animal or plant, the most important factor is to ensure that it is proprietary blend free. When you track your food, it’s important to know what you’re ingesting to help you reach your goals. For example, most plant protein powders will list the sources of plant proteins they use, but what they won’t disclose is how much of each source they have. Without knowing the amounts, you won’t know what types of micronutrients you’re getting or what your protein is really made of. So whatever you do, make sure your protein powder provides transparency and lists the ingredients and amounts to make a better informed decision.

Now, should you be using animal vs. plant protein powder to reach your health and fitness goals? Well, of course, that depends on a few different factors. Before you buy protein powder, ask yourself a few questions. What are my goals? Am I trying to lose more body fat? Do I want to incorporate more plant-based foods in my diet? Does it even matter? In any type of protein powder, whether that be whey, egg, rice, or plant protein, the carbs will always be negligible. If absorption rate is what’s important to you, opt for an animal based protein powder like whey isolate, egg, or casein.

Related: How to Create a Muscle Building Vegetarian Meal Prep

Take Home Message

There is no one size fits all for what type of protein you should opt for. We all have different nutrient requirements, goals, dietary needs, and health profiles. The truth is that you can get all of your protein from plants, animals, or both. At this point, there’s not enough clinical evidence, to give you a definitive right or wrong answer if plant or animal protein is better. Both are inherently good, with their own pros and cons. Having a mix of plant and animal protein sources in your diet, is always going to provide more nutritional adequacy than strictly choosing one over the other.

If you do choose, either way you’re going to lack in some essential nutrients, whether you like it or not. Studies do favor animal protein in terms of athletic performance and goals. To the average person, that may not make a big difference, but to you, it probably does. Bottom line is that there is a lot to consider, and it’s not that simple. If you’re counting macros, chances are the distinction doesn’t matter that much, so long as you meet your macronutrient goals. A diet should be well-rounded with a collective amount of protein sources, both animal and plant.