For decades, fitness enthusiasts and nutrition experts in Thailand and around the world have debated whether eating animal-based or plant-based protein is better for muscle building. Now, new research from the University of Illinois—published in Medicine & Science in Sports & Exercise—has found that both plant and meat proteins support muscle growth equally, so long as overall protein intake is sufficient. This finding could shift the way Thai athletes, gym-goers, and health-conscious citizens approach their diets, expanding acceptance of plant-based eating patterns while reassuring those who consume traditional animal protein sources.
According to the research, which recruited 40 healthy and physically active men and women aged 20 to 40, there is no significant difference between vegan and omnivorous diets in their ability to fuel muscle growth during resistance training. The study also overturned a popular belief: spreading protein intake evenly across meals does not appear to improve muscle protein synthesis compared to consuming more protein at certain times of the day. As long as daily intake is adequate—around 1.1 grams per kilogram of body weight—both animal and plant proteins support the muscle-building response during strength training. These findings challenge a core tenet among Thai fitness communities, where “ข้าวมันไก่,” grilled chicken with rice, and grilled pork skewers (หมูปิ้ง) have long been seen as essential recovery meals for gym enthusiasts and athletes.
The research team, led by Professor Nicholas Burd, set out to answer three critical questions: whether the source of protein matters for muscle gain, whether protein should be distributed evenly throughout the day, and whether a moderate but sufficient amount of daily protein affects any of these outcomes. In a controlled environment, participants were randomly assigned to vegan or omnivorous diets and then further split into groups that ate their protein in either an even or uneven distribution across meals over a nine-day intervention. All participants engaged in regular resistance training. Their muscle protein synthesis was tracked using heavy water labeling, a precise method that allows scientists to see how proteins are incorporated into muscle tissue.
What’s especially relevant for Thai readers is that the vegan participants ate a varied, whole-food diet rather than relying on high levels of processed supplements—a more realistic scenario for those contemplating a plant-based shift. As Professor Burd explained, “[The] longstanding belief or the current dogma was that animal-based protein sources were better, particularly for the muscle-building response.” This assumption was based on single-meal studies showing animal protein led to a more immediate spike in muscle protein synthesis. However, when protein intake is measured over multiple meals and days, the differences disappear. Simply put: “If anyone asks me what’s the best type of food they should eat for muscle building, I’ll tell them: It’s the kind you put in your mouth after exercise. As long as you’re getting sufficient high-quality protein from your food, then it really doesn’t make a difference,” Burd stated (https://neurosciencenews.com/diet-muscle-growth-exercise-28679/).
Historically, the notion that animal protein is superior has deep roots in societies like Thailand, where rice and fish, pork, and chicken dominate the cuisine, especially in meals aimed at physical recovery or muscle maintenance. The belief that plant-based proteins—such as tofu (เต้าหู้), tempeh (เต็มเป), or various legumes—are “incomplete” and thus inferior for athletes has deterred many from adopting plant-based diets. However, this new evidence calls for a reassessment of Thailand’s culinary traditions, especially as the plant-based food movement gains momentum among health-conscious Bangkokians and young people seeking sustainable diets (https://studyfinds.org/plant-based-diets-build-muscle-as-well-as-meat-based-protein/).
Researchers ensured the vegan diets in the study contained “complete proteins,” appropriately combining foods so all essential amino acids were present. This is crucial for Thai readers considering a plant-based diet: combining foods like rice and beans, or tofu and whole grains, can create a balanced amino acid profile suitable for muscle growth. Furthermore, the recommended daily protein intake used in the study—1.1 grams per kilogram of body weight—is close to what many Thais already consume, and is lower than the massive intakes often cited by bodybuilders. For example, a person weighing 60 kg would need just 66 grams of protein per day, an amount easily attained from traditional dishes, whether featuring grilled pork or stir-fried tofu.
Significantly, the research also found no benefit in “timing” one’s protein intake for muscle growth, dismantling another widespread belief. Whether participants ate their protein throughout the day or concentrated larger portions in the evening, their muscle protein synthesis showed no difference. This flexibility may be reassuring for Thai office workers and students who often skip breakfast or eat lightly during the day before having a larger dinner at home or at a night market. No need to stress over strict meal planning—the key is ensuring enough total protein by day’s end.
Internationally, similar results have been found in prior studies, but much of the previous research used higher-than-typical protein intakes (1.6-1.8 g/kg/day) and relied heavily on protein supplements, especially in vegan groups. The new study more closely mirrors the way Thais actually eat, involving a mix of everyday foods—another reason its findings are especially relevant for a local context.
However, despite the strengths of this trial, the researchers noted some limitations: participants were all healthy, young adults, which may not represent the metabolic needs of older individuals or those with chronic illnesses. Also, the study duration was nine days, so longer-term impacts are not yet clear. “More research is needed to determine if these results hold over weeks or months, especially for those engaging in intensive training or experiencing age-related muscle loss,” the authors stated in the published article.
Understanding the Thai context, this research comes at a time when plant-based dining is gaining traction in Bangkok and other urban centers, spurred by both health concerns and environmental motivations. Supermarkets, street stalls, and even fast-food chains now offer tofu burgers, meatless “หมูกรอบ” (crispy pork), and soy-based alternatives. For Thais who are Buddhist or participate in the annual “เจ” vegetarian festival, these findings provide scientific reassurance that abandoning animal products temporarily—or even long-term—does not put muscle strength at risk if dietary diversity and sufficient protein intake are observed.
Looking to the future, the study’s key message—eat enough high-quality protein, regardless of source—could help reduce the stigma around plant-based diets and provide a nutritional pathway for Thais who wish to balance tradition, health, and sustainability. With the rise of chronic non-communicable diseases such as obesity, diabetes, and cardiovascular disease across Thailand, such flexibility in protein source could support national health goals while respecting cultural preferences.
For those eager to put this science into practice, here are some actionable recommendations:
- Aim for at least 1.1 grams of protein per kilogram of body weight per day, whether you choose animal or plant sources.
- Enjoy a variety of proteins. Pair plant-based foods (like rice and beans, or tofu with grains) to ensure all essential amino acids are covered.
- Don’t stress about spreading protein perfectly across meals—focus on achieving your daily target.
- If you follow a vegan diet, plan meals so they contain complementary proteins, and don’t rely solely on processed foods. Eating a range of whole grains, legumes, nuts, and vegetables is effective.
- Remember, muscle building is also driven by regular resistance exercise, not diet alone.
For Thai athletes, students, professionals, or anyone trying to stay healthy, this research is a timely reminder that there are many pathways to strong muscles—including those rooted in plant-based traditions long practiced across the Kingdom. Explore the vibrant flavors of local cuisine, experiment with Thai vegan classics like “ผัดไทยเจ” (vegan Pad Thai) or “แกงเขียวหวานเจ” (vegan green curry), and fuel your workouts with confidence, knowing it’s the total protein in your diet—not its source—that counts most.
Source references: