Is Plant-Based Protein Lower Quality Than Animal Protein?

Is plant-based protein enough for your health?

More and more people are choosing a plant-based diet. Maybe you want to feel fitter, boost your energy, or live more sustainably.

You stock up on beans, tofu, and nuts. But then you hear: “Plant-based protein is harder to digest and lower quality than animal protein. You need much more of it.”

It’s normal to start doubting. Are you doing it right? Will you miss out on essential nutrients?

At Plants for Health, we know the facts. In this article, you’ll discover what science really says about plant-based protein—and why you can confidently include more of it in your diet.

How is protein quality measured?

Researchers often use two scoring systems to compare protein quality: PDCAAS (Protein Digestibility-Corrected Amino Acid Score) and DIAAS (Digestible Indispensable Amino Acid Score).

These methods are useful in contexts where people have limited access to food and rely on just one or two protein sources. The scores then show which foods help prevent deficiencies.

In Western countries, where we eat a variety of foods, these scores are far less relevant.

Plant-based protein and amino acids

PDCAAS and DIAAS assess proteins individually. Sources with fewer essential amino acids score lower. As a result, many plant-based proteins rank below animal-based proteins.

But here’s the truth: plant-based proteins contain all essential amino acids. By eating a variety of foods each day, you get everything your body needs.

Why these scores underestimate plant-based protein

Most PDCAAS and DIAAS studies are performed on rats or pigs fed raw food. But:

• Humans are not rats or pigs.
• We don’t eat raw beans or grains.
• Cooking makes plant-based protein easier to digest.

Because of this, these scores often underestimate the real nutritional value of plant-based proteins in human diets.

What do human studies show?

Recent human studies with better methods confirm that the differences in digestibility between animal and plant-based protein are small—often just a few percentage points.

Some plant-based foods, like mung beans, may score slightly lower. But in a balanced diet, these differences are negligible.

How much protein do you need?

Global recommendations are the same for vegans, vegetarians, and meat eaters: about 1.0 gram of protein per kilogram of body weight per day.

For a 60 kg (132 lbs) woman, that’s around 60 grams per day. Even if plant-based protein is assumed to be 10% less digestible, you’d only need an extra 5–10 grams daily.

Examples of 5–10 grams of additional plant-based protein:

• 1–2 tablespoons pumpkin seeds
• 100–200 g soy yogurt
• 1 slice whole-grain bread with nut butter

Easy to achieve with a varied plant-based diet.

Conclusion: plant-based protein is not lower quality

Plant-based protein is digestible, complete, and fits perfectly into a healthy diet. You can safely choose more plant-based foods without worrying about deficiencies.

Eating well doesn’t have to be complicated. At Plants for Health, we show you practical ways to build a healthy lifestyle.

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