It can be very difficult to find accurate data for an herbal supplement. Sometimes the rich history of an herb can mean that there is clear consensus on whether it works–because Ginseng has been around for generations, for instance, there’s ample data on its use for blood sugar, inflammation, and blood pressure.
In other cases, the traditional history of an herb can work against it. With Bacopa (Bacopa monnieri), Ayurvedic medicine has prescribed it for centuries for a number of symptoms. In the scientific literature, this may have worked against it, as some analysis seems to be biased against it, despite ample evidence of its use as a nootropic.
Largest Body of Evidence
There are around a dozen primary clinical studies that show support for a positive correlation between Bacopa and cognitive function. I’ve pulled the four studies that are the most representative of the group. I’ll include a link later to literature reviews with links to all the relevant studies.
A randomized, double blind study of college students asked the participants to perform several cognitive behavior tests. One group had 150 mg of Bacopa for two weeks, the other group had a placebo. The Bacopa group not only had statistically significantly better scores, but also higher levels of serum calcium. The researchers further explained that calcium in the brain can have antioxidant effects, and in conjunction with the primary mechanism of Bacopa, may be responsible for increased Acetylcholine activity.
In the Elderly
Generally speaking, the longer a test group takes a trial substance, the better the data are at establishing a correlation. This is usually due to how long some nutrients take to build up in our system. Following this model, a group of researchers took 48 non-dementia people over the age of 65 and had one randomized group take 300 mg of Bacopa a day for 12 weeks.
At the end of the study, the test group had significantly higher scores on a standardized Auditory Verbal Learning Test (AVLT) and better marks in another cognitive metric, the Stroop Test.
Key to this finding is that these were healthy individuals. Like the student trial, this offers support that Bacopa can help all populations, not just those seeking to reverse the effects of aging.
In a Mid-Range Population
Bringing together the data sets from a student population and an elderly population, scientists discovered not only the same significantly improved cognitive function in AVLT tests following Bacopa treatment, but also even better results for lowered anxiety. This study also used the 300 mg dosage, and interestingly, took performance measurements at 5 weeks and then again at 12 weeks. They found the best results, perhaps unsurprisingly, at 12 weeks, supporting the notion that Bacopa is a substance best taken over longer time periods.
We’ll see later in our review of the literature that not everyone is sold on the results such as we’ve covered so far. Critics point out that data is inconsistent across supposedly standardized AVLT testing. One such study often pointed to as showing no evidence is one conducted in the last year. They found slower reaction times among their Bacopa test group compared to the placebo group–but they found more accurate answers from the Bacopa group.
Faster doesn’t always mean better, as anyone who has graded tests can attest to. So Bacopa participants having slower reaction times isn’t necessarily proof that Bacopa doesn’t work, especially if that same group had the right answer more often than the faster, placebo group.
And only looking at the behavioral data can be misleading–perhaps they simply had a group of prudent, slow test-takers in the Bacopa group, after all. Luckily, this team of researchers also took brain scans of all the participants. In the Bacopa group, researchers found increased White Matter diffusion throughout the brain, and increased dispersion of neurites in the Gray Matter. In layman’s terms, the actual brain chemistry of the Bacopa group was improved after treatment.
Beyond looking at the raw results of various primary test studies, it can be helpful at times to read through literature reviews written by the peers of the primary researchers. Literature reviews are often high-level summaries of the existing state of a given field, and are written generally by experts who can connect dots that non-scientists may not be able to see.
The first review of the literature compiled data from 6 human studies, covering 17 different cognitive tests. The aggregated data showed that Bacopa can increase memory function, though these researchers found little evidence of other cognitive function increases.
A later review, however, with 9 human trials and over 500 patients taken into account, did find improved cognition with Bacopa use, including in the areas of reaction time and attention.
The next two literature reviews have taken the matter a step further, and looked into the actual bio-chemical mechanisms of Bacopa. It’s worth mentioning that these sorts of papers are generally only written after a correlation is established. After all, no one will fund a study into how something works if, well, it doesn’t work at all.
In the first study of this kind, researchers suggested that the evidence shows Bacopa working by:
A few years later, Alzheimer’s researchers fleshed out this research with actual chemical analysis of how Bacopa works within each of these mechanisms. This study even highlighted the benefits of Bacopa for new-learning among people who take it.
The One Outlier
No good science writer can leave out a prominent voice that disagrees with the rest. In this case, we have a literature review published in the high-profile journal Nature. This review looked at 11 studies–each of which had statistically significant positive results–and somehow concluded that there is no evidence.
The authors’ reasoning goes along two lines:
Breaking that down a little further, suppose two groups are given a muscle supplement or a placebo. After 12 weeks, the test group can bench press, on average, 5 more pounds than the placebo group–but everyone in the test group saw an increase, while no one in the placebo group did. Is five pounds a lot? Not really, no. But the fact that statistically, all the test group saw an improvement while none of the placebo group did means that the supplement does indeed work.
In short, I’ve included this literature review because it is a well-read and well-respected publication that, in my opinion, has accepted a poor literature review with slip-shod reasoning and writing. Their own data table shows 4 studies with improved ALVT recall scores, 4 studies with improved ALVT learning, 3 studies with better logical memory, 5 studies with better digit cognition, 3 studies with better attention.
And then they conclude that there is “little to no evidence” that Bacopa works. I mention it here as evidence of, in this case, what I would consider a bias among certain academics, as well as analysis of what might otherwise be seen as proof of negative results.
I’ve written about dozens of herbal remedies for hundreds of applications, and I’ve rarely seen so much evidence for one substance showing positive correlation to a test outcome. Bacopa, it appears, has significant benefits in application to memory, learning, attention, and even mood.