Ursolic Acid Benefits: What the Research Says

Ursolic acid is a natural compound found in apples, herbs such as rosemary, and many other plants, and it’s sold as a supplement to build muscle and burn fat. Most of that reputation comes from mouse studies. This guide looks at the real ursolic acid benefits shown so far in people, how strong that evidence is, and what we know about safety.

Summary

In mice, ursolic acid built muscle, raised brown fat and protected against weight gain on a high-fat diet. In people, the handful of small trials is mixed: one Korean study of 16 men found extra strength gains, but a better-controlled Brazilian trial found no added muscle or strength, and a 2024 meta-analysis found no effect on body weight, body fat or blood sugar. Ursolic acid benefits for gym-goers are unproven, and long-term safety hasn’t been studied.

What is ursolic acid?

Ursolic acid is a triterpene, a type of plant compound. It’s found in many fruits, vegetables and herbs [1], and it’s especially plentiful in apples [2].

In lab and animal studies, ursolic acid has shown anti-inflammatory and antioxidant effects, along with effects on fat cells, blood sugar and muscle [1]. That long list is why it turns up in muscle-building and fat-loss products. But results in test tubes and mice often don’t carry over to people, so the human studies below are what matter most.

Where the muscle-building idea came from

The excitement started with a 2011 study from the University of Iowa [2]. Researchers listed the genes that switch on or off when human muscle wastes away (for example, during fasting or after a spinal cord injury). They then searched a large database of compounds for one with the opposite pattern, and ursolic acid came out on top.

When they tested it in mice, ursolic acid reduced muscle wasting and made muscles grow [2]. It seemed to work by boosting insulin and IGF-1 signaling in muscle. (IGF-1, or insulin-like growth factor 1, is a hormone that helps muscles grow.) The mice also had less body fat and lower blood sugar, cholesterol and triglycerides [2].

A follow-up mouse study in 2012 found that ursolic acid in a high-fat diet increased muscle mass, grip strength and brown fat, a type of fat that burns energy to make heat. The mice gained less weight and had less fat in their livers [3].

A 2013 rat study added another piece. When ursolic acid was injected into the belly straight after an electrically stimulated “workout”, the muscle’s growth signal (called mTORC1) stayed switched on for longer than with a placebo injection [4].

These are interesting findings, but they come from animals given ursolic acid in their food or by injection. They don’t tell us whether a capsule does the same thing in people.

Does ursolic acid build muscle or strength in people?

Only a few small human trials have tested this, and they don’t agree.

A short-term signaling study (no effect). In a 2016 study at Baylor University, 9 resistance-trained men took 3 g of ursolic acid, 3 g of the amino acid leucine, or a placebo straight after a leg workout, on three separate occasions. Ursolic acid showed up in their blood, but it didn’t change muscle growth signals (Akt and mTORC1) or blood insulin and IGF-1 compared with placebo [5]. That’s the opposite of what the rat study suggested.

The Korean trials (positive, but with limits). In a 2014 study, 16 men with at least three years of weight-training experience trained six days a week for 8 weeks and took either 450 mg a day of ursolic acid from rosemary leaf extract (9 men) or a placebo (7 men) [6]. The capsules came from a US sports-supplement company. Leg strength, measured on an isokinetic machine (which tests how hard you can push or pull at a fixed speed), rose more in the ursolic acid group. In that group, body fat percentage also fell and IGF-1 and irisin levels rose compared with their own starting levels, but muscle mass didn’t change [6].

Irisin is a hormone-like substance thought to be released by working muscle. It got a lot of attention around this time, but in 2015 researchers showed that the commercial antibody test kits widely used to measure it (this study used one) also pick up other blood proteins, which calls those irisin results into question [7].

A 2017 pilot study from the same research network, with 16 trained men and 450 mg a day for 8 weeks, found lower blood markers of muscle damage with ursolic acid. This one had no placebo: the comparison group simply trained without a supplement. Changes in body fat and lean mass were small and not statistically significant (they could have been due to chance) [8].

The Brazilian trial (no effect). In a double-blind trial published online in 2020 (neither the men nor the researchers knew who got what), 22 active young men did the same 8-week training program, ate a high-protein diet of about 1.6 g of protein per kg of body weight, and took 400 mg a day of ursolic acid or a placebo [9]. Both groups gained about 1.1 kg (2.4 lb) of muscle, and neither muscle nor strength gains differed between the groups. The authors concluded ursolic acid “had no synergic effect” on muscle strength or mass [9].

Older women. In a 2021 trial, 26 postmenopausal women (average age 61) did a combined exercise program for 8 weeks and took 450 mg a day of ursolic acid or a placebo. The ursolic acid group’s handgrip strength rose by about 1.8 kg more than the placebo group’s, but nothing else differed, including waist size, blood pressure, blood tests and body composition [10].

So the human evidence for muscle is thin: a few trials with 9 to 26 people each, lasting 8 weeks or less, and the best-controlled one found nothing extra.

Does ursolic acid help with fat loss or blood sugar?

In mice on high-fat diets, ursolic acid reduced weight gain, improved blood sugar control and cut liver fat [2, 3]. In people, the results are weaker.

A 2017 Mexican trial gave 24 people with metabolic syndrome (a cluster of risk factors such as a large waist, high blood pressure and high blood sugar) either 150 mg of ursolic acid or a placebo once a day for 12 weeks [11]. In the ursolic acid group, half the patients no longer met the criteria for metabolic syndrome, and their weight, waist size and fasting blood sugar fell (weight went from about 75.7 to 71 kg). But this was a very small study, the summary reports these as before-and-after figures for the ursolic acid group without giving the placebo group’s results, and the authors described the remission as “transient” [11].

Other trials haven’t backed this up. In the older women’s trial above, about 38% of each group no longer met the criteria for metabolic syndrome by the end, whether they took ursolic acid or placebo [10]. That suggests the exercise program, not the supplement, made the difference.

A 2024 meta-analysis (a study that pools the results of earlier trials) combined six human trials using about 50 to 450 mg a day [12]. Compared with control groups, ursolic acid didn’t significantly change body weight, body mass index, waist size, body fat percentage, lean mass, blood pressure, fasting blood sugar, insulin, triglycerides or HDL (“good”) cholesterol. The authors concluded it “had no significant effect on the cardiometabolic risk factors in adults” [12].

Other claimed ursolic acid benefits

Inflammation. Ursolic acid lowers inflammation in many animal and lab studies [1]. In people, results are mixed. A trial from the same Brazilian research group, in 27 healthy men doing resistance training and taking 400 mg a day for 8 weeks found no change in blood levels of cytokines (signaling proteins involved in inflammation, such as IL-6 and TNF-alpha) [13]. But a small Iranian trial in 22 inactive men doing resistance training found lower levels of several inflammation markers (CRP, IL-6 and TNF-alpha) with ursolic acid than with placebo [14].

Cancer, liver and heart health. Ursolic acid has been studied as a possible anti-cancer agent and for liver, heart and brain health, but this work is almost entirely in cells and animals [1]. There’s no good evidence that an ursolic acid supplement prevents or treats any disease in people.

Ursolic acid dosage and safety

The human supplement trials used about 50 to 450 mg a day, mostly for 8 to 12 weeks [6, 9, 10, 11, 12], and one short study gave single 3 g doses [5]. There’s no official recommended dose, and nobody knows whether one dose works better than another.

Small amounts of ursolic acid come naturally from everyday fruits, vegetables and herbs [1]. Supplements are a different matter, because there’s very little human safety data:

• The supplement trials described here were small and lasted 12 weeks at most, so they couldn’t pick up uncommon or long-term side effects.
• In a Chinese phase I trial (an early safety study) of an intravenous (IV, into a vein) form of ursolic acid being developed as a cancer drug, liver toxicity and diarrhea limited how high the dose could go, and other side effects included nausea, bloating and skin rash [15]. That’s a different way of taking it from a capsule, but it shows ursolic acid isn’t automatically harmless at high exposures.
• We found no safety studies in pregnancy or breastfeeding, so it’s best avoided then.
• If you have liver problems or take prescription medicines, check with your doctor or pharmacist first.

If muscle gain is your goal, the basics are consistent training and enough total protein (see our article on whether the anabolic window is real). For another supplement sold as a natural muscle booster, see our review of D-aspartic acid and testosterone. A related plant compound is covered in our post on corosolic acid.

The bottom line on ursolic acid

Ursolic acid looked impressive in mice, building muscle and brown fat and protecting against weight gain. In people, the evidence is small and mixed: one Korean trial found extra strength, a better-controlled Brazilian trial found no extra muscle or strength, and a 2024 meta-analysis found no effect on weight, body fat or blood sugar. Until larger, longer human trials are done, the ursolic acid benefits on supplement labels are mostly promises from animal research, and its long-term safety is unknown.

This article is for general information only and isn’t medical advice. Talk to your doctor or another qualified health professional before starting a new supplement. See our medical disclaimer.

References

1. Seo DY, Lee SR, Heo JW, et al. Ursolic acid in health and disease. Korean J Physiol Pharmacol. 2018;22(3):235-248. doi:10.4196/kjpp.2018.22.3.235
2. Kunkel SD, Suneja M, Ebert SM, et al. mRNA expression signatures of human skeletal muscle atrophy identify a natural compound that increases muscle mass. Cell Metab. 2011;13(6):627-638. doi:10.1016/j.cmet.2011.03.020
3. Kunkel SD, Elmore CJ, Bongers KS, et al. Ursolic acid increases skeletal muscle and brown fat and decreases diet-induced obesity, glucose intolerance and fatty liver disease. PLoS One. 2012;7(6):e39332. doi:10.1371/journal.pone.0039332
4. Ogasawara R, Sato K, Higashida K, Nakazato K, Fujita S. Ursolic acid stimulates mTORC1 signaling after resistance exercise in rat skeletal muscle. Am J Physiol Endocrinol Metab. 2013;305(6):E760-E765. doi:10.1152/ajpendo.00302.2013
5. Church DD, Schwarz NA, Spillane MB, et al. L-Leucine increases skeletal muscle IGF-1 but does not differentially increase Akt/mTORC1 signaling and serum IGF-1 compared to ursolic acid in response to resistance exercise in resistance-trained men. J Am Coll Nutr. 2016;35(7):627-638. doi:10.1080/07315724.2015.1132019
6. Bang HS, Seo DY, Chung YM, et al. Ursolic acid-induced elevation of serum irisin augments muscle strength during resistance training in men. Korean J Physiol Pharmacol. 2014;18(5):441-446. doi:10.4196/kjpp.2014.18.5.441
7. Albrecht E, Norheim F, Thiede B, et al. Irisin – a myth rather than an exercise-inducible myokine. Sci Rep. 2015;5:8889. doi:10.1038/srep08889
8. Bang HS, Seo DY, Chung YM, et al. Ursolic acid supplementation decreases markers of skeletal muscle damage during resistance training in resistance-trained men: a pilot study. Korean J Physiol Pharmacol. 2017;21(6):651-656. doi:10.4196/kjpp.2017.21.6.651
9. Lobo PCB, Vieira IP, Pichard C, et al. Ursolic acid has no additional effect on muscle strength and mass in active men undergoing a high-protein diet and resistance training: a double-blind and placebo-controlled trial. Clin Nutr. 2021;40(2):581-589. doi:10.1016/j.clnu.2020.06.004
10. Cione JGC, Verlengia R, Barbosa CGR, et al. No additional effects of ursolic acid supplementation associated with combined exercise program on metabolic syndrome of postmenopausal women: a double-blind, randomized, placebo-controlled trial. Clin Nutr ESPEN. 2021;44:143-149. doi:10.1016/j.clnesp.2021.05.031
11. Ramírez-Rodríguez AM, González-Ortiz M, Martínez-Abundis E, Acuña Ortega N. Effect of ursolic acid on metabolic syndrome, insulin sensitivity, and inflammation. J Med Food. 2017;20(9):882-886. doi:10.1089/jmf.2017.0003
12. Rafiee P, Rasaei N, Amini MR, et al. The effects of ursolic acid on cardiometabolic risk factors: a systematic review and meta-analysis. Future Cardiol. 2024;20(3):151-161. doi:10.1080/14796678.2024.2349476
13. Lobo PCB, Pimentel GD. Ursolic acid does not change the cytokine levels following resistance training in healthy men: a pilot balanced, double-blind and placebo-controlled clinical trial. Biomed Pharmacother. 2022;145:112289. doi:10.1016/j.biopha.2021.112289
14. Asghari E, Rashidlamir A, Hosseini SRA, Moazzami M, Samarghandian S, Farkhondeh T. Synergism effects of ursolic acid supplementation on the levels of irisin, C-reactive protein, IL-6, and TNF-α during high-intensity resistance training in low activity men. Cardiovasc Hematol Disord Drug Targets. 2020;20(2):138-144. doi:10.2174/1871529X19666190918144727
15. Wang XH, Zhou SY, Qian ZZ, et al. Evaluation of toxicity and single-dose pharmacokinetics of intravenous ursolic acid liposomes in healthy adult volunteers and patients with advanced solid tumors. Expert Opin Drug Metab Toxicol. 2013;9(2):117-125. doi:10.1517/17425255.2013.738667