Bacopa monnieri (commonly called bacopa) is a perennial herb that has been used for centuries in Indian Ayurveda traditional medicine. Practitioners of Ayurveda claim varying benefits from bacopa, including improved cognitive function. Studies show that bacopa may slightly improve scores on some cognitive tests in some people. Scientists are exploring other claims that it can protect against a variety of diseases, but the evidence so far is minimal.
Many small clinical trials have looked at effects on cognition but no human studies— either clinical trials or observational studies—have looked at protection from cognitive decline. Our search identified:
Several clinical trials have explored whether bacopa may have any cognitive benefit. However, these trials have largely been small, and the study designs have made it challenging to draw firm conclusions from either individual studies or the studies as a whole. A systematic review and meta-analysis looked at 11 double-blinded randomized controlled trials testing a supplement containing only bacopa compared to a control. All but one study reported at least one statistically significant improvement on at least one neuropsychological measure. However, no two studies found benefits of bacopa using the same assessment. Most studies only found one or two types of assessments of memory to be significantly improved with bacopa treatment, and those changes were small [1]. Other systematic reviews or meta-analyses have similarly found potential effects on different cognitive domains [2; 3].
Bacopa has a long history of use in Ayurveda and preclinical research studies have identified biological mechanisms by which it might protect the brain from aging and perhaps Alzheimer’s disease [4; 5; 6; 7; 8; 9; 10]. However, no scientific studies in humans have confirmed that these biological benefits occur in a clinically meaningful way, or that they can protect from cognitive decline or dementia.
Bacopa has not been evaluated on its own as a treatment for dementia in randomized controlled trials.
Bacopa is a widely used supplement generally considered to be safe, though its risks have not been well-studied and likely vary by individual. In small clinical trials, bacopa was reported to be safe for healthy adults when used for three months [2]. The most common side effects are gastrointestinal symptoms such as nausea and abdominal cramps. Bacopa may affect thyroid hormone levels or modulate the cholinergic system. Therefore, people who take thyroid drugs or drugs that affect cholinergic pathways (e.g., acetylcholinesterase inhibitors or cholinergic drugs) should be cautious. Bacopa may also worsen certain conditions, including bradycardia, gastrointestinal obstruction, peptic ulcers, pulmonary conditions such as asthma, or urogenital tract obstruction [11].
Some sources of bacopa may be unsafe. Depending on where the plant is grown, its extracts could contain mercury, lead, and other heavy metals [12]. Consider choosing supplements whose content has been verified by a third party.
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.
In clinical trials on cognitive function, bacopa extract is often administered at 300 mg/day, though doses have ranged from 250 to 600 mg/day [2]. Some bacopa supplements are standardized to contain a certain percentage of bacosides, the components of bacopa that are believed to be biologically active [13]. Without this standardization, the doses of bacosides might change unexpectedly in different lots of supplements sold by the same company. However, no specific dose or formulation of bacosides has been shown to be particularly effective in clinical trials [1; 2].
Full scientific report (PDF) on Cognitive Vitality Reports
Photo: Forest and Kim Starr