Protein is having a moment—and for good reason. Whether you’re trying to gain muscle or simply stay strong as you age, protein is key for building and maintaining muscle.
But with so many options out there—specifically animal vs. plant-based options—it’s easy to get confused.
So, what’s the best type of protein for muscle growth? Keep reading to find out—or skip ahead to the bottom line.
The facts: Your muscles need protein to grow. This is through a process called muscle protein synthesis (MPS).
When you eat protein, your body breaks it down into amino acids, which help repair and rebuild muscle tissue.
Protein needs vary based on age, sex, and goals, among other things.
- General adults: In general, everyone 18 and older needs 0.8 grams of protein per kilogram of bodyweight (g/kg) each day. (Something to keep in mind: This amount is the minimum to maintain health and doesn’t take physical activity into account.)
- Older adults: For people 65 years and older, research suggests upping protein to 1.0-1.2 g/kg per day to prevent muscle loss associated with aging.
- Athletes: Active people should take in 1.4-2.0 g/kg every day to help with recovery and support muscle growth from training.
Sorry, vegans and vegetarians: Not all proteins are created equal.
Animal proteins—like meat, fish, dairy, eggs, whey, and casein—reign supreme for muscle growth. This is because they are complete proteins (contain all nine essential amino acids) and are higher in leucine, a key part of protein synthesis.
Plant proteins, on the other hand—legumes, most nuts and seeds, brown rice, and oats—are primarily incomplete proteins (missing some essential amino acids) and are lower in leucine.
That doesn’t mean plant proteins are useless for muscle growth—just that you may need more of them and in varied types to get the same bang for your buck.
Yes—but you might need to be a little more strategic.
There are some complete plant-based proteins that can fortify a vegan or vegetarian diet. Those include:
- Soy products
- Quinoa
- Chia seeds
- Hemp seeds
Studies also show plant-based protein blends—which make them complete proteins with enough leucine—can yield similar results for muscle growth gram for gram compared to animal proteins like whey.
If you’re a vegan or vegetarian, there are steps you can take to optimize muscle growth with plant-based protein:
- Combine incomplete proteins (whole grains and legumes, whole grains and nuts or seeds, legumes and nuts or seeds)
- Eat as many complete plant-based proteins as possible
- Set a higher daily protein goal and try to hit it
To build and maintain muscle, the type of protein matters—but not as much as the total amount you consume each day.
If you’re an athlete, older adult, or on a plant-based diet, try to make most of the protein you eat complete proteins—or combine your incomplete proteins—and make sure you’re getting enough high-quality protein throughout the day in your meals and snacks.
For personalized guidance, consult a registered dietitian or healthcare provider who can tailor protein needs to your goals.