Continuing our deep dive into the science behind protein intake, this blog tackles one of the most widely discussed topics in modern nutrition: animal-based versus plant-based proteins. There are several perspectives involved in this discussion — ethical considerations, environmental concerns — but, much like the other pieces on the website, the main focus will be to figure out whether it is viable, from a muscle and health perspective, to switch to a plant-based diet.
Where the debate gets stuck
A lot of the discourse on this topic has been very polarising, especially within the realms of social media. On such platforms, nutrition dialogue is usually approached in an extreme manner rather than tackled with the nuance necessary when discussing science-backed topics. Regardless of the discourse surrounding this topic, most of the rhetoric can be explained in two straightforward points:
- First, plant-based diets (or vegan diets, as often these are grouped together) are generally considered the more ethical option and better for the environment.
- Second, you cannot get enough high-quality protein from plant-based diets.
Both deserve a closer look.
Beyond ethics: what the environmental data shows
While the question of morality and environmental repercussions is outside the scope of this blog piece, it is essential to mention them briefly as these hold a lot of weight in this conversation. Opinions on the ethics of current-day animal agriculture are very individual and thus the perspectives are highly personal. However, there are papers that do a good job at tackling the environmental perspective of the discourse and discussing its repercussions.
Since the early 2000s, scientists have been pointing out how current food systems are unsustainable due to the significant land, water, and energy resources required, with animal-based foods being more resource-demanding than plant-based diets (Pimentel & Pimentel, 2003). These points of contention are fascinating and relevant given the influence they hold over public nutrition and food guidelines released by governments.
Recently, the Dutch government updated its Schijf van Vijf (Wheel of Five) earlier this year, implementing changes that further promote plant-based eating — such as reducing the recommendations for meat consumption and increasing recommendations for legume consumption (Voedingscentrum, 2026). However, all countries have different aims when releasing such recommendations: the American government released a newly defined pyramid-style guideline focused on consuming whole foods with a mix of plant and animal-based options (Dietary Guidelines for Americans, 2025–2030).
So, what does the science say about our final point of contention — protein quality?
The protein quality question
To begin with, many plant-based options contain lower amounts of amino acids essential for stimulating muscle protein synthesis (Pinckaers et al., 2021), or their digestibility seems to be lower (Kashyap et al., 2018, 2019). On the surface, this is the argument used to claim that plant-based diets cannot match animal-based ones for building muscle. But the picture is more nuanced — there are ways to mitigate these issues:
- Preparation and processing methods can be used to increase digestibility in plant-based products (Devi et al., 2018).
- Consuming larger portions can compensate for differences in amino acid quantity.
- In young men, both protein sources have been shown to be viable for supporting muscle growth and strength increases over a multi-week training schedule (Hevia-Larraín et al., 2021).
- Older adults, however, seem to require larger amounts of plant-based protein to achieve a muscle protein synthesis response comparable to that seen with animal-based protein consumption (Gorissen et al., 2016). Even so, it seems that as long as total protein intake is planned accordingly over a multi-day period, the choice of diet and protein source matters less in the elderly (Domić et al., 2025).
- Fortification of plant-based products or the use of isolated proteins can increase the quality or the digestibility of plant-based proteins.
- Finally, individuals can — and most usually do — consume a mix of proteins during meals (Pinckaers et al., 2021), which further blunts the difference between sources.
What it means in practice
From a muscle perspective, it is clear that both plant-based and animal-based proteins are viable sources to ensure adequate protein intake. If someone chooses one approach over the other based on environmental, ethical, or cultural reasons, that choice can be adequately implemented into their daily routine.
At the end of the day, the choice of protein matters far less than establishing a balanced, realistic nutritional approach. The total amount you hit consistently across the week — and how well that approach fits your lifestyle — will always matter more than whether the protein on your plate had a face or a root.
📚 Curious how much protein you actually need per day? The previous article in this series — How much protein should we consume? — breaks down the numbers, plus an interactive calculator to estimate your personal target.
References
Devi, S. M., Kurpad, A. V., Devi, S., Kashyap, S., & Sheshshayee, M. S. (2018). Determining intrinsically labeled plant-based protein digestibility. Food Science and Human Wellness.
Dietary Guidelines for Americans, 2025–2030. U.S. Department of Agriculture and U.S. Department of Health and Human Services.
Domić, J., Pinckaers, P. J. M., Grootswagers, P., Verdijk, L. B., & van Loon, L. J. C. (2025). Plant- versus animal-based protein sources in the diet of older adults: A narrative review. Advances in Nutrition.
Gorissen, S. H. M., Horstman, A. M. H., Franssen, R., Crombag, J. J. R., Langer, H., Bierau, J., Respondek, F., & van Loon, L. J. C. (2016). Ingestion of wheat protein increases in vivo muscle protein synthesis rates in healthy older men in a randomized trial. The Journal of Nutrition, 146(9), 1651–1659.
Hevia-Larraín, V., Gualano, B., Longobardi, I., Gil, S., Fernandes, A. L., Costa, L. A. R., Pereira, R. M. R., Artioli, G. G., Phillips, S. M., & Roschel, H. (2021). High-protein plant-based diet versus a protein-matched omnivorous diet to support resistance training adaptations. Sports Medicine, 51(6), 1317–1330.
Kashyap, S., Shivakumar, N., Varkey, A., Duraisamy, R., Thomas, T., Preston, T., Devi, S., & Kurpad, A. V. (2018). Ileal digestibility of intrinsically labeled hen’s egg and meat protein determined with the dual stable isotope tracer method in Indian adults. The American Journal of Clinical Nutrition, 108(5), 980–987.
Kashyap, S., Varkey, A., Shivakumar, N., Devi, S., Reddy B, H. R., Thomas, T., Preston, T., Sreeman, S., & Kurpad, A. V. (2019). True ileal digestibility of legumes determined by dual-isotope tracer method in Indian adults. The American Journal of Clinical Nutrition, 110(4), 873–882.
Pimentel, D., & Pimentel, M. (2003). Sustainability of meat-based and plant-based diets and the environment. The American Journal of Clinical Nutrition, 78(3), 660S–663S.
Pinckaers, P. J. M., Trommelen, J., Snijders, T., & van Loon, L. J. C. (2021). The anabolic response to plant-based protein ingestion. Sports Medicine, 51(Suppl 1), 59–74.
Voedingscentrum. (2026). De vernieuwde Schijf van Vijf. Retrieved from voedingscentrum.nl.