Ursolic acid is a compound present in many fruits and herbs, such as apple peels, cranberry juices, grape skins, holy basil, rosemary, thyme, oregano, sage, and other herbs. While preclinical studies suggest it has anti-oxidant and anti-inflammatory actions, no studies in humans have evaluated whether ursolic acid improves cognitive function or brain health. Ursolic acid is also not absorbed very well by the body. Ursolic acid ingested through the diet is safe, but long-term safety of ursolic acid supplements has not been tested.
Although numerous preclinical studies have been carried out, no clinical evidence in humans exist to date. Our search identified:
No clinical studies have tested whether ursolic acid can prevent cognitive decline or dementia.
In various preclinical models of cognitive impairment, ursolic acid treatment improved cognitive functions while reducing oxidative stress, brain inflammation, and cellular stress [1; 2; 3; 4; 5; 6; 7]. However, these promising preclinical findings have not been confirmed in humans.
No human research has examined whether ursolic acid can benefit patients with dementia. Although some preclinical studies have shown benefits in models carrying biological markers of Alzheimer’s disease [8; 9], these benefits have not been extended to dementia patients.
Ursolic acid consumed in the diet is safe. No large, long-term, randomized controlled clinical trials have tested ursolic acid supplements, and therefore, long-term safety for supplements is unknown. Drug interactions with ursolic acid are also not known. Because ursolic acid is not absorbed very well by the body, clinical studies in cancer patients have used a drug delivery vehicle called liposomes, which are spherical lipid vesicles, wherein ursolic acid was packaged [10]. This special form of ursolic acid has caused some adverse events such as elevated liver enzymes, fever, and abdominal distension (i.e., bloating).
NOTE: This is not a comprehensive safety evaluation or complete list of potentially harmful drug interactions. It is important to discuss safety issues with your physician before taking any new supplement or medication.
Ursolic acid is available over the counter as a supplement. It is also present in food, such as apple peel, cranberry juice, grape skin, holy basil, rosemary, thyme, oregano, sage, and other herbs. Rosemary and sage have the highest content of ursolic acid, 3.0% and 1.8%, respectively [11]. Apple skin contains 1.4% ursolic acid. The appropriate dose of ursolic acid has not been determined. In people with metabolic syndrome, a daily dose of 150 mg was tested in a clinical trial [12].
Key chemical information on ursolic acid on the National Institutes of Health’s PubChem
A full scientific report (PDF) at Cognitive Vitality Reports