Benefits of Protein Powder: Plant Vs. Animal Sources

The most important of the amino acids for building lean muscle and losing fat are called BCAAs, or Branched Chain Amino Acids.

Together, the three BCAAs (leucine, isoleucine, and valine) account for as much as 33% of muscle tissue. Here’s a brief overview of each: 

1. Leucine is a branched chain amino acid that helps your body synthesize protein.
2. Isoleucine is a BCAA that can help your body regulate blood sugar levels and ensure your muscle cells are metabolizing sugar (instead of fat cells).
3. Valine is the least important BCAA for body composition (it’s also the least-studied).

Protein powders can come from plant or animal sources, each having a different make-up of amino acids.

Different Types of Protein Powders (and Their Benefits and Risks)

There’s some intriguing science about the most common types of protein powder sources that we’ll explore a bit further …

Benefits and Risks of Whey Protein Powder

As mentioned, whey protein has been studied more than any other protein powder. A quick search of “whey protein powder” on PubMed brings up close to 600 studies to date.

While you can certainly find studies like this one that showed no link between whey protein and body composition, the overall body of evidence seems to suggest that whey works for building muscle. 

A meta analysis (a review of a group of studies) published in the Journal of the American College of Nutrition looked at 14 clinical studies including a total of 626 adults and concluded that whey protein powder has favorable effects on body composition (and is even more effective when combined with resistance training).

However, there are some side effects associated with whey protein, particularly on kidney and liver function and for those with sensitivities and allergies to dairy.

Benefits and Risks of Casein Protein

Casein is a slower digesting form of milk-based protein. T

When it comes to the effectiveness of casein vs whey protein, one study showed that casein did not have any noticeable differences on body composition, strength, and power and agility compared to whey.

Casein has a few flaws as a protein source too. One study found that it promotes the growth of prostate cancer cells.  And since it’s milk-based, it’s not a good choice if you’re sensitive to dairy.

Benefits and Risks of Brown Rice Protein Powder

Rice protein is a plant-based protein powder used by vegans, vegetarians, and people who can’t tolerate dairy products like whey and casein. In one study published in the journal Nutrition, researchers found that rice protein had similar effects on body composition as whey.

In other words, there was no difference between the group of subjects that took rice protein and the one that took whey protein; both experienced positive body composition changes.

One of the main complaints you’ll hear about rice protein is it’s high in potentially toxic heavy metals like arsenic, lead, cadmium, and mercury.

While it’s true consuming high amounts of some of these metals can lead to negative health effects, heavy metals are in all plants that grow in soil. Here’s a quote from Jon Barron’s research article on the topic:

In summary, don’t have a knee jerk reaction to the label “heavy metals.” (Both calcium and iron are technically heavy metals.) Yes, obviously, when it comes to “toxic” heavy metals, less is better than more. But the issue is far more nuanced than a simple label–or even numbers on a chart for that matter. You have to factor in whether or not the element actually has any “proven” toxicity (tungsten has no demonstrated toxicity), whether it’s organic or inorganic (organic arsenic is virtually ignored by the body), and whether it’s bound or unbound (bound cadmium has only 2-6% absorbability).

Yes, plant-based protein powders contain higher levels of heavy metals than animal proteins. But it’s important to understand how these heavy metals actually get absorbed in your body before jumping to conclusions.

That’s why it’s up to you as the consumer to ask the manufacturer of your protein powder what their heavy metal contents are, especially if they use rice protein (if they won’t share those numbers, it’s a big red flag).

And choose a rice protein from organic brown rice sourced outside of China to avoid ingesting potential chemical pesticides and herbicides.

Benefits and Risks of Pea Protein

Pea protein is another popular plant-based source of protein. It’s becoming increasingly prevalent in vegetarian / vegan / dairy free powders for several reasons:

1. It’s a “complete” protein source that contains an impressive BCAA profile.
2. Pea protein powder is among the most hypoallergenic of all protein powders, as it contains no gluten or dairy.
3. It’s easy on the gut and doesn’t cause bloating, a common side effect of many other protein powders from animal sources.
4. It has been shown in small studies to have similar effects to whey protein on body composition.
5. Pea protein has a PDCAA (digestible indispensable amino acid score) of .89 (whey is 1). When combined with rice, hemp, and/or soy in certain combinations, you can get this number to 1.0–the same as whey!

While pea protein hasn’t been studied as much as whey or soy, it is a promising protein source for those looking for alternatives to dairy proteins. Again, organic pea protein is always a safer choice because you’re ingesting less pesticides.

Benefits and Risks of Soy Protein Powder

Soy protein is another popular plant-based protein powder. Most men should avoid it because it contains isoflavones and phytoestrogens that share similarities with estrogen.

It’s often extracted using hexane, a petroleum-based solvent … and most soy comes from genetically modified (GMO) soybeans.

However, according to several studies, soy protein may have body composition benefits for older women.

One study showed that a daily supplement of soy protein prevented increases in subcutaneous and total abdominal fat in older women. Another showed soy protein had a mild effect on body composition in elderly women.

One caveat: whey has been shown to be more effective than soy for improving lean body mass when combined with resistance training. So if lean body mass is your goal, you may want to consider other protein sources than soy if you’re using a protein powder.

How Is Protein Powder Made?

Protein powder processing methods depend on the type of protein and the company making it.

Whey Protein Processing

Most commercial whey protein powders are made using a high-heat, acid-flushed, “ion exchange” process to separate the whey from the cow’s milk. This can strip away vital nutrients.

So why do companies use it?

Because processing protein with acids is cheaper, of course.

If you decide a whey protein supplement is best for you, I recommend choosing one that’s from grass-fed cows, cold processed, and has zero sugar and as few ingredients as possible.

What if you can’t tolerate milk-based products or prefer plant-based protein powders though?

Plant Based Protein Processing

Many of the supposedly-healthy plant proteins used in supplements and packaged foods today are processed using hexane, a petroleum-based neurotoxin. Using hexane is an efficient and highly profitable way for food manufacturers to remove oil from plants and separate the protein.

If you decide a plant protein powder is a better option for you, look for plant-based protein powders that are organic and “enzymatically sprouted,” which means all-natural enzymes are used rather than chemicals to separate the protein from the plant.

Also, sprouting grains used in plant-based powders (e.g., rice, pea, amaranth) increases many of the plants’ key nutrients, including B vitamins, vitamin C, folate, fiber, and essential amino acids often lacking in grains, such as lysine. Sprouted grains may also be less allergenic to those with grain sensitivities.

Who Should Take Protein Powder?