Advertisement
This ad is displayed using third party content and we do not control its accessibility features.
Close Banner
Advertisement
This ad is displayed using third party content and we do not control its accessibility features.

Looking To Put On Muscle? 3 Reasons To Reconsider Your Plant Protein

Emma Loewe
Author:
September 30, 2024
Emma Loewe
By Emma Loewe
mbg Contributor
Emma Loewe is the former Sustainability and Health Director at mindbodygreen. She is the author of "Return to Nature: The New Science of How Natural Landscapes Restore Us" and the co-author of "The Spirit Almanac: A Modern Guide To Ancient Self Care." Emma received her B.A. in Environmental Science & Policy with a specialty in environmental communications from Duke University. In addition to penning over 1,500 mbg articles on topics from the water crisis in California to the rise of urban beekeeping, her work has appeared on Grist, Bloomberg News, Bustle, and Forbes.
Woman drinking a protein shake and stretching before a workout
Image by BONNINSTUDIO / Stocksy
September 30, 2024

We're living in prime time for protein powders, with whey, hemp, soybean, and pea protein all readily available for your sipping pleasure.

All protein powders look alike and taste at least vaguely similar, so it can be easy to think that their benefits are also comparable. But don't be fooled: Animal protein powders (like whey) and plant powders (like soy and pea) don't always have the same impact on lean muscle mass.

In general, plant proteins are lower in the amino acid building blocks needed to spur muscle growth. Let's unpack that further: Here are a few reasons you may not be getting the results you want with a plant protein.

Plant proteins are lower in leucine

The biggest difference between plant and animal proteins comes down to their leucine content. Leucine is the amino acid in protein that's most directly implicated in muscle growth.

The branched-chain amino acid activates the body's mTOR pathway1, which controls the anabolic (growth) and catabolic (breakdown) signaling of skeletal muscle. "You can think of the BCAA leucine as a trigger or 'its go-time' button for muscle protein synthesis (i.e., the critical cellular process for building muscle)," explains mindbodygreen's former vice president of scientific affairs, Ashley Jordan Ferira, Ph.D., RDN.

You need to consume around 2.5 to 3 grams of leucine at a time to trigger this muscle growth, Don Layman, Ph.D., a leading amino acid researcher, previously explained on the mindbodygreen podcast.

Animal proteins are naturally higher in leucine, so it's reasonable to reach this 2.5-gram threshold in just one serving. That's not the case with plant proteins. While whey protein powder typically has about 8 to 10% leucine content, soy is 7.8%, while hemp is 5.1%2. This means it would take 25 grams of whey protein to trigger muscle growth (a standard one- to two-scoop serving size) but up to 50 grams of hemp (which could take up to four scoops or more).

While some vegan powders combine different types of plant proteins in order to get closer to this leucine threshold, even the most thoughtfully formulated of them often fall short.

Beyond leucine, animal proteins also contain all the other essential amino acids in the amounts we need for muscle growth, maintenance, and repair. Plant proteins (except for soy) are considered incomplete proteins; they don't contain adequate amounts of all the essential amino acids to meet the minimal human requirements.

Because of these differences, whey protein has proved to be more effective for muscle growth than plant proteins in many clinical trials. In one scientific literature review, whey protein was found to be better at increasing lean body mass3 than soy protein. When put head-to-head against pea protein in a controlled trial, whey was also better at decreasing muscle soreness4 following prolonged exercise.

This isn't to say that taking plant protein won't support your muscle health at all. It will just likely be less effective than whey, and you may need to consume a much larger serving5 to see the same benefits.

Plant proteins aren't digested as efficiently

Protein digestibility is measured by a PDCAAS, or protein digestibility-corrected amino acid score6. This score measures how much of a protein's amino acids our bodies absorb, with the highest possible score being 1.0 (100%).

Soy protein isolate is the only plant protein with a PDCAAS of 1.0—others, like pea, fall closer to the 0.78 to 0.91 range. So, you may need to consume even larger portions of them to ensure that you're getting the amino acids your body needs and can put to use for muscle growth.

Plant proteins are more likely to contain heavy metals

Finally, plant proteins are more likely to contain heavy metals like lead than animal proteins—which makes eating them in large quantities less appealing.

A highly cited report from the watchdog group Clean Label Project tested 53 brands of protein powder and found that, on average, plant proteins contained twice the amount of lead per serving as animal proteins.

They found measurable levels of lead in 75% of plant protein powders tested (including organic varieties).

Research shows that animal proteins that have undergone additional filtration, like whey protein isolate, tend to have the least amount of heavy metal contamination7 due to their lack of plant ingredients.

The takeaway

Plant protein powders can be a convenient tool for reaching your daily protein quota while getting some fiber, healthy fats, and phytonutrients along the way. That said, they likely won't be as helpful for strength goals as animal proteins, which are higher in essential amino acids like leucine and more efficiently digested.

At the end of the day, the best protein powder is the one that works for you—plant or animal. But if you're looking to choose one over the other for enhanced muscle health, go with an animal protein like whey. Just be sure to look for one that's low in sugar and other funky additives.

Watch Next

Enjoy some of our favorite clips from classes

Watch Next

Enjoy some of our favorite clips from classes

What Is Meditation?

Mindfulness/Spirituality | Light Watkins

Box Breathing

Mindfulness/Spirituality | Gwen Dittmar

What Breathwork Can Address

Mindfulness/Spirituality | Gwen Dittmar

The 8 Limbs of Yoga - What is Asana?

Yoga | Caley Alyssa

Two Standing Postures to Open Up Tight Hips

Yoga | Caley Alyssa

How Plants Can Optimize Athletic Performance

Nutrition | Rich Roll

What to Eat Before a Workout

Nutrition | Rich Roll

How Ayurveda Helps Us Navigate Modern Life

Nutrition | Sahara Rose

Messages About Love & Relationships

Love & Relationships | Esther Perel

Love Languages

Love & Relationships | Esther Perel

Related Videos (10)

What Is Meditation?

Box Breathing

What Breathwork Can Address

The 8 Limbs of Yoga - What is Asana?

Two Standing Postures to Open Up Tight Hips

How Plants Can Optimize Athletic Performance

What to Eat Before a Workout

How Ayurveda Helps Us Navigate Modern Life

Messages About Love & Relationships

Love Languages

Advertisement
This ad is displayed using third party content and we do not control its accessibility features.

More On This Topic

more Food
Advertisement
This ad is displayed using third party content and we do not control its accessibility features.
Advertisement
This ad is displayed using third party content and we do not control its accessibility features.