Is the Vegan Muscle Myth Dead? A New Study Challenges What We Thought We Knew

By Marc Lobliner, IFBB Pro

In the world of nutrition, few topics generate more debate than whether or not you can build the same amount of muscle on a vegan diet compared to an omnivorous one. We’ve all seen the viral posts, influencer transformations, and supplement brands promising “plant-based gains” with no compromises.

But a brand-new study just hit the headlines—and it’s making people question the whole narrative.

Let’s break down what the science says, what it really means for vegans, and how to make sure you’re not leaving muscle gains on the table.

The Study: What Did It Find?

Published in PLOS One in 2024, this study looked at 193 healthy adult vegans and analyzed not just their total daily protein intake, but also their essential amino acid intake.

Here’s what researchers found:

• 75% of vegans hit the recommended daily protein target of 0.8g/kg of bodyweight.

• BUT less than half met the recommended intakes for lysine and leucine.

Why does that matter? Because these are two of the most critical amino acids for building muscle and maintaining overall metabolic health.

Why Amino Acids Matter More Than Protein Alone

Protein is made up of amino acids. Think of them as the building blocks of muscle. Of the 20 amino acids, 9 are essential, meaning your body can’t make them on its own.

Among these, leucine is the standout. It’s the amino acid that triggers muscle protein synthesis (MPS) – the process by which your body builds new muscle tissue.

If you’re low on leucine, your ability to build or preserve lean mass takes a major hit.

And lysine? It supports collagen production, immune function, and calcium absorption. It's also commonly deficient in many plant-based protein sources.

The Problem With Plant Proteins

Many plant proteins are incomplete, meaning they lack one or more essential amino acids. While this doesn’t mean you can’t get all the amino acids you need from plants, it does mean you have to be strategic.

For example:

• Wheat, rice, oats → low in lysine

• Legumes (beans, lentils) → low in methionine

• Pea and soy → more complete, but still lower in leucine than whey or meat

This isn’t a dig on plant-based eating. It’s just how the amino acid profiles of different foods stack up.

So Can Vegans Build Muscle?

Yes—but it’s not automatic. Hitting your protein number (say, 1 gram per pound of bodyweight) isn’t enough unless you’re also covering your amino acid needs.

If you’re vegan and not getting enough leucine or lysine, you may:

• Experience slower recovery

• Struggle to maintain or build lean mass

• Experience immune dysfunction or nutrient absorption issues

This study shows that many vegans, even if well-fed in terms of grams of protein, are undernourished at the amino acid level.

How Vegans Can Fix This

If you’re vegan or mostly plant-based, here are smart strategies to optimize your muscle-building potential:

1. Combine Proteins: Mix grains and legumes to cover amino acid gaps. Rice + beans, quinoa + lentils, or soy + oats.

2. Eat More Leucine-Rich Plant Foods: Soy, lentils, peanuts, hemp seeds, and spirulina are higher in leucine.

3. Supplement with EAAs or Leucine: If you’re training hard, a vegan-friendly essential amino acid supplement or added leucine can bridge the gap.

4. Choose Smart Protein Powders: I use Ambrosia Planta, a plant-based protein that’s fortified with essential amino acids to mimic the complete profile of whey.

5. Aim Higher Than RDA: Don’t settle for 0.8g/kg. For muscle building and performance, shoot for 1.6–2.2g/kg (or 0.7–1g/lb).

The Bottom Line

This new study doesn’t say vegans can’t build muscle. What it says is that most vegans aren’t eating the right mix of amino acids to do it effectively.

If you want to optimize recovery, strength, and long-term performance, it’s not just about how much protein you eat—it’s about what that protein is made of.

So don’t fall for the myth that all protein is created equal.

Whether you eat meat, plants, or both, get strategic, fill the gaps, and build the body you want.

By Marc Lobliner, IFBB Pro

In the world of nutrition, few topics generate more debate than whether or not you can build the same amount of muscle on a vegan diet compared to an omnivorous one. We’ve all seen the viral posts, influencer transformations, and supplement brands promising “plant-based gains” with no compromises.

But a brand-new study just hit the headlines—and it’s making people question the whole narrative.

Let’s break down what the science says, what it really means for vegans, and how to make sure you’re not leaving muscle gains on the table.

The Study: What Did It Find?

Published in PLOS One in 2024, this study looked at 193 healthy adult vegans and analyzed not just their total daily protein intake, but also their essential amino acid intake.

Here’s what researchers found:

• 75% of vegans hit the recommended daily protein target of 0.8g/kg of bodyweight.

• BUT less than half met the recommended intakes for lysine and leucine.

Why does that matter? Because these are two of the most critical amino acids for building muscle and maintaining overall metabolic health.

Why Amino Acids Matter More Than Protein Alone

Protein is made up of amino acids. Think of them as the building blocks of muscle. Of the 20 amino acids, 9 are essential, meaning your body can’t make them on its own.

Among these, leucine is the standout. It’s the amino acid that triggers muscle protein synthesis (MPS) – the process by which your body builds new muscle tissue.

If you’re low on leucine, your ability to build or preserve lean mass takes a major hit.

And lysine? It supports collagen production, immune function, and calcium absorption. It's also commonly deficient in many plant-based protein sources.

The Problem With Plant Proteins

Many plant proteins are incomplete, meaning they lack one or more essential amino acids. While this doesn’t mean you can’t get all the amino acids you need from plants, it does mean you have to be strategic.

For example:

• Wheat, rice, oats → low in lysine

• Legumes (beans, lentils) → low in methionine

• Pea and soy → more complete, but still lower in leucine than whey or meat

This isn’t a dig on plant-based eating. It’s just how the amino acid profiles of different foods stack up.

So Can Vegans Build Muscle?

Yes—but it’s not automatic. Hitting your protein number (say, 1 gram per pound of bodyweight) isn’t enough unless you’re also covering your amino acid needs.

If you’re vegan and not getting enough leucine or lysine, you may:

• Experience slower recovery

• Struggle to maintain or build lean mass

• Experience immune dysfunction or nutrient absorption issues

This study shows that many vegans, even if well-fed in terms of grams of protein, are undernourished at the amino acid level.

How Vegans Can Fix This

If you’re vegan or mostly plant-based, here are smart strategies to optimize your muscle-building potential:

1. Combine Proteins: Mix grains and legumes to cover amino acid gaps. Rice + beans, quinoa + lentils, or soy + oats.

2. Eat More Leucine-Rich Plant Foods: Soy, lentils, peanuts, hemp seeds, and spirulina are higher in leucine.

3. Supplement with EAAs or Leucine: If you’re training hard, a vegan-friendly essential amino acid supplement or added leucine can bridge the gap.

4. Choose Smart Protein Powders: I use Ambrosia Planta, a plant-based protein that’s fortified with essential amino acids to mimic the complete profile of whey.

5. Aim Higher Than RDA: Don’t settle for 0.8g/kg. For muscle building and performance, shoot for 1.6–2.2g/kg (or 0.7–1g/lb).

The Bottom Line

This new study doesn’t say vegans can’t build muscle. What it says is that most vegans aren’t eating the right mix of amino acids to do it effectively.

If you want to optimize recovery, strength, and long-term performance, it’s not just about how much protein you eat—it’s about what that protein is made of.

So don’t fall for the myth that all protein is created equal.

Whether you eat meat, plants, or both, get strategic, fill the gaps, and build the body you want.