Scientists test whether plant-based eating can rival meat when matched for protein and calories
It’s easy to overlook the quiet, steady decline of muscle as we age. You might not notice it when carrying groceries or going for a walk, but over time, tasks that were once second nature—like climbing stairs or lifting a suitcase—start to feel harder. This creeping loss of strength and function, known as sarcopenia, is more than just an inconvenience. It’s a serious issue that threatens mobility, independence, and quality of life.
Admittedly, I approach this topic as a mediator—someone who values both the nutritional benefits of a well-rounded diet and the potential of plant-based eating to contribute to health. In recent years, I’ve been incorporating more plant-based options into my diet, driven by my interest in research and the broader health benefits of plants as part of a balanced, diverse approach to eating. A recent study published in The Journal of Nutrition takes on one of the most debated questions in nutrition science: Can a well-planned vegan diet support muscle health as effectively as an omnivorous one? Researchers tested whether a diet built around high-quality plant proteins could match an omnivorous diet in preserving muscle protein synthesis (MPS) among older adults. The results were surprising: with the right combinations and quantities of plant proteins, the vegan diet performed just as well.
For those exploring plant-based eating—or simply considering ways to include more plants in their diet—this finding is promising. Let’s explore what the science says and how to translate it into practical strategies for healthy aging.
The Aging Muscle: Why Protein Matters
Muscle loss is a hallmark of aging. Beginning as early as our 30s, we lose 1–2% of muscle mass per year, with the rate accelerating in our 60s and beyond. Strength declines even faster, and the combination of reduced muscle and strength significantly increases the risk of frailty, falls, and loss of independence. The role of dietary protein in combating sarcopenia is well-established. Protein supports MPS, the process by which our bodies repair and build muscle tissue. However, aging brings a phenomenon called “anabolic resistance,” where muscles respond less efficiently to protein intake. This means older adults require more protein per meal to achieve the same muscle-building response as younger individuals.
Traditionally, animal proteins—rich in leucine and other essential amino acids (EAAs)—have been considered the gold standard for triggering MPS. Plant proteins, by contrast, are often seen as less effective due to their lower leucine content and incomplete amino acid profiles. But as the recent study demonstrates, plant proteins can hold their own when consumed strategically.
The implications are profound. For aging adults, incorporating more plant-based foods doesn’t have to mean sacrificing muscle health. Instead, it requires a thoughtful approach to protein selection and meal planning to overcome the challenges of anabolic resistance.
What Makes Plant Proteins Different?
Not all proteins are created equal. The quality of a protein source depends on two factors: its digestibility and amino acid profile. Animal proteins score high on both counts, as they contain all nine essential amino acids (EAAs) in the right ratios and are easily absorbed by the body. Plant proteins, on the other hand, are often incomplete—lacking one or more EAAs—and less digestible due to their fiber and anti-nutritional components. However, these limitations aren’t insurmountable. Combining complementary plant proteins, such as rice and peas or hummus and whole-grain pita, creates a complete amino acid profile. Fortified plant-based products, like soy and pea protein isolates, also offer concentrated sources of high-quality protein.
The study in The Journal of Nutrition highlighted this point. Researchers found that older adults consuming a carefully planned vegan diet achieved MPS rates comparable to those on an omnivorous diet. The key was diversity: no single plant protein source could do the job alone. By including a variety of protein-rich foods, the vegan diet delivered the amino acids needed to support muscle health. For those adopting plant-based eating, the message is clear: diversity and intentionality are essential for meeting protein needs and maintaining muscle mass.
(Photo: The Journal of Nutrition)
The Synergy of Exercise and Plant Proteins
Diet alone isn’t enough to counteract sarcopenia. Exercise, particularly resistance training, plays a critical role in maintaining muscle mass and function as we age. The combination of plant proteins and exercise is where the magic happens. The study demonstrated that physically active participants—those averaging over 10,000 steps per day and engaging in strength training—achieved similar muscle health outcomes on both vegan and omnivorous diets. This finding reinforces the idea that exercise enhances the body’s ability to utilize dietary protein, regardless of its source. For plant-based eaters, exercise becomes even more important. Because plant proteins may require larger doses to trigger MPS, regular resistance training primes muscles to respond more effectively. Activities like weightlifting, bodyweight exercises, and even plyometrics can help maximize the benefits of plant proteins.
However, the study also raised an interesting question: what happens in sedentary individuals? Without the amplifying effect of exercise, it’s unclear whether plant proteins alone can meet the muscle health needs of less active older adults. This highlights the critical role of lifestyle in making plant-based diets work for healthy aging.
Cardiometabolic Benefits of Plant-Based Diets
While animal proteins may have a slight edge in supporting muscle health, plant-based diets offer additional benefits for overall well-being, particularly for heart health. Aging populations face an increased risk of cardiovascular disease, making the cardiometabolic advantages of plant proteins an important consideration. Studies show that plant-based diets reduce LDL cholesterol, improve blood pressure, and decrease inflammation. The recent Journal of Nutrition study found similar results, with vegan participants experiencing significant reductions in LDL cholesterol and other risk markers compared to their omnivorous counterparts. These benefits are largely attributed to the high fiber content and abundance of bioactive compounds in plant-based foods.
However, plant-based diets aren’t without their challenges. Older adults need to pay attention to potential nutrient gaps, such as vitamin B12, iron, zinc, and omega-3 fatty acids, which are less bioavailable in plant foods. Fortification, supplementation, and careful meal planning can help address these concerns while reaping the cardiometabolic rewards of plant proteins.
Practical Strategies for Effective Plant-Based Eating
Incorporating more plant proteins into your diet doesn’t require a full shift away from animal proteins—it’s about finding balance. Here are some strategies to make the most of plant-based options:
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Prioritize high-protein foods: Include lentils, chickpeas, tofu, tempeh, quinoa, and edamame in your meals.
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Combine proteins: Pair complementary proteins, like beans and rice or nut butter on whole-grain bread, to ensure a complete amino acid profile.
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Supplement the diet: Use plant-based protein powders to boost intake where necessary.
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Spread protein intake: Aim for 20–30 grams of protein per meal to maximize MPS.
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Stay active: Combine your plant-based diet with regular resistance training to amplify the benefits.
Plant proteins aren’t just suitable for healthy aging—they’re a powerful, science-backed option for supporting muscle protein synthesis while delivering additional cardiovascular benefits. Whether you’re exploring ways to incorporate more plant-based options or interested in the broader health benefits, the evidence shows that plant proteins can match the effectiveness of animal proteins. By combining diverse plant protein sources, staying physically active, and addressing any nutritional gaps, plant proteins offer a viable, balanced, and sustainable approach to promoting long-term health and vitality.