Complete plant proteins: What they are and why they matter

If you’ve spent any time exploring plant-based eating, you’ve probably come across the phrase ‘complete protein’, but what does it actually mean? And is it something we need to consider?

What is a complete protein?

Proteins are made up of building blocks called amino acids. There are 20 in total, and 9 of these are considered essential (our bodies can’t make them), so we have to get them from food. A complete protein contains all 9 of these essential amino acids in roughly the right amounts.

Animal based proteins like meat, are naturally complete. This has long been used to suggest that plant-based diets are somehow nutritionally inferior. But the reality is more nuanced.

Can plants be complete proteins?

Yes. There are several plant-based foods that are complete proteins, and plenty more that can easily be combined to cover all essential amino acids. The idea that you need to eat all amino acids in one meal is outdated. What really matters is variety across the day.

Still, for those wanting to know which plants do it all in one go, here are some complete plant proteins worth knowing.

Quinoa

This ancient grain (technically a seed) is a complete protein and also high in fibre, iron, and magnesium. One cup of cooked quinoa provides about 8 grams of protein. It’s easy to use in place of rice, stirred into salads, or made into porridge.

Soy

Soybeans are protein powerhouses. Tofu, tempeh, soy milk, and edamame are all complete proteins, making soy one of the most versatile plant-based options. Tempeh in particular offers fermented goodness for gut health as well.

Buckwheat

Despite the name, buckwheat isn’t wheat or even a grain, it’s a seed. It cooks up like rice and is great in both savoury and sweet dishes. It’s a complete protein and naturally gluten-free.

Chia Seeds

Tiny but mighty, chia seeds are complete proteins packed with omega-3 fatty acids and fibre. Two tablespoons give you around 4 grams of protein. They’re brilliant in overnight oats, smoothies, or as a pudding base.

What about incomplete proteins?

The truth is, most plant foods contain all nine essential amino acids, they’re just not always present in the ideal ratios. This is where the idea of complementary proteins comes in. Pairing foods like rice and beans, hummus and pitta, or peanut butter on wholegrain bread helps create a full amino acid profile.

You don’t need to worry about hitting every amino acid at every meal. As long as your overall diet includes a range of legumes, grains, nuts, and seeds, you’re likely doing just fine.

The bottom line

You absolutely can get enough complete protein on a plant-based or flexitarian diet. Whether you’re planning menus for a retreat, cooking for a family with mixed dietary needs, or just wanting to feed yourself well, complete plant proteins are easy to incorporate when you know where to find them.

Aim for diversity. A colourful, varied plate will almost always lead you in the right direction - nutritionally and flavour-wise.