Rosemary on your roast chicken? Delicious.
Rosemary for building muscle and burning fat? Now that’s unexpected.
As strange as it sounds, science has been uncovering some pretty compelling effects of a natural compound found in rosemary—it’s called ursolic acid (it’s just one of the three very cool compounds in rosemary).
And it plays a role in how your body handles strength, fat storage, and energy.
What Is This Ursolic Acid In Rosemary?
Ursolic acid is found not only in rosemary but also in apple peels, basil, cranberry skins, oregano, and thyme. What makes it interesting is how it interacts with cellular pathways tied to muscle preservation, fat metabolism, and energy use.
The interesting bit is that researchers actually didn’t start studying ursolic acid because of fitness trends. They found it while looking for compounds that prevent muscle atrophy — the muscle loss that occurs during aging, illness, or inactivity.
Preventing Muscle Atrophy (Where It All Began)
A study thread that initially put ursolic acid in the spotlight — not for bodybuilding, but for muscle preservation under stress — found that ursolic acid:
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Increased muscle mass in fasted mice (something that normally leads to muscle loss)
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Reduced denervation-induced atrophy, a model often used to mimic injury-related muscle loss
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Activated pathways known to preserve lean tissue
A landmark 2012 study in mice found that when their diet was supplemented with ursolic acid, they developed more muscle, stronger muscles, and greater endurance. The treated mice also showed more brown fat (the “fat‑burning” type), higher calorie expenditure, less body fat, better blood sugar control, and reduced fatty liver. These results were linked to increased activation of the Akt signaling pathway — a well-known trigger for muscle growth and metabolic benefits.
That said, (and this is important) these findings were observed in mice under tightly controlled conditions (high-fat diet, defined ursolic acid dosage, and consistent environment). Translating those effects to humans is far from guaranteed.
Early human research is mixed: one small pilot showed ursolic acid might reduce muscle damage during training, but other work found no significant gains in muscle mass or strength in active men.
Bottom line: If combined with proper nutrition, regular exercise, and healthy lifestyle habits, it could be a helpful ally in metabolic health or muscle maintenance.
Fat Loss & Metabolism: The Calorie-Burning Effect
Now, things get even more interesting as ursolic acid’s effects on fat metabolism are coming to the fore.
In one animal study, researchers observed that ursolic acid:
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Reduced body weight gain
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Decreased white fat (especially abdominal fat)
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Improved fatty liver conditions
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Increased energy expenditure
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Boosted brown fat activity (the calorie-burning type of fat that produces heat)
Brown fat activation is a big deal. It’s the same mechanism activated by cold exposure, certain types of exercise, and some metabolic therapies.
Cell studies conducted on cells extracted from mice showed that ursolic acid:
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Inhibited formation of new fat cells (adipogenesis)
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Activated LKB1/AMPK, the same cellular energy sensor triggered by movement, fasting, and calorie restriction
In simpler terms, ursolic acid made fat cells behave as if they were in an energy-efficient, calorie-burning mode.
Ursolic Acid and Human Studies
While most ursolic acid research is in animals, there is one early human study worth discussing.
It followed resistance-trained men taking 450 mg/day of ursolic acid alongside their normal training.
Compared to training alone, the ursolic acid group showed:
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Greater strength gains
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Significant reductions in body fat percentage
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Better overall training adaptations
It’s a small study, but it echoes what’s been seen in animals. And it’s promising enough to justify more research.
How Ursolic Acid Might Work
Even with all the data, researchers are still piecing together ursolic acid’s full mechanism. But here’s what we know so far in a nutshell:
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It supports muscle protein synthesis. By activating pathways like Akt/mTOR, it helps muscles repair and grow.
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It boosts mitochondrial efficiency. More efficient mitochondria = improved endurance + better fat oxidation.
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It activates brown fat. This increases calorie burning through thermogenesis.
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It activates AMPK. Often called the body’s metabolic “master switch,” AMPK improves energy sensing and reduces fat storage.
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It reduces inflammation and oxidative stress. Important for recovery, metabolic health, and longevity.
Real Talk About Rosemary and Ursolic Acid Supplements
While rosemary naturally contains ursolic acid, the amount you get from cooking with it is extremely small. That’s why most of the studies exploring muscle or metabolic benefits rely on standardized ursolic acid extracts, not culinary herbs.
But as with any supplement, quality matters. Potency and purity can vary widely between brands, so it's important to choose products from companies that provide transparent sourcing, proper testing, and clear standardization.
And before adding ursolic acid to your routine, it’s wise to speak with your healthcare provider, especially if you take medications or have underlying health conditions. Ursolic acid can influence metabolic pathways, which means guidance from a professional can help you use it safely and effectively.
If you're looking for a natural, rosemary-forward option that supports overall wellness, you may want to explore BCP formulations that pair rosemary’s bioactive compounds with other supportive ingredients; formulations like the Relief F2 Rosemary extract-based oral spray. It is designed with careful attention to safety, quality, and real-world use.
Final Words
Ursolic acid won’t replace good training or transform health overnight, but it’s a compelling natural compound being studied for muscle growth and metabolic support.
The animal research is strong. The cellular data is consistent. And the early human findings are encouraging, even if small. So while there’s still a lot to learn, rosemary’s lesser-known compound is worth keeping an eye on. It’s another reminder that sometimes, nature hides remarkable chemistry in the most familiar places.