Does it work?

Can Bacopa help improve memory?

BACKGROUND

Bacopa is a herbal remedy made from Bacopa monnieri.This creeping plant grows in marshes and wetlands throughout India and other parts of Southeast Asia. The herbal remedy is also called Brahmi, a word which derives from Brama, the creator god in Hinduism. However, Brahmi is a term that can refer to any substance believed to improve brain function because of the connection between the brain and creativity.

Bacopa has a long history of use in Ayurvedic medicine, which is the traditional medicine of India. It has been used for many different purposes, including as a treatment for epilepsy, insomnia, asthma, rheumatism and heart failure, and more generally as a nerve tonic. More recently, Bacopa has developed a reputation for enhancing cognitive abilities and protecting people against memory loss and dementia.

EVIDENCE FROM STUDIES

Studies in the 1960s, where the behaviour of animals given Bacopa was observed, suggested that their memory was improved by the herb. In laboratory tests, studies found that Bacopa contains compounds that protect nerve cells against damage similar to that occurring with dementia. Such studies suggested Bacopa could work either by effecting neurotransmitters or through a general antioxidant effect.

Over the past 10 years, a number of randomised controlled trials have been conducted. The first enrolled healthy adults with half taking 300mg Bacopa and the other half taking a placebo. After 12 weeks (but not earlier), those taking Bacopa had higher scores on learning and memory tests.

However, another study with a similar design and using the same remedy found significant improvements in only one of several cognitive tests given. Healthy participants scored better on a test measuring retention of new information, but not on other tests measuring short-term memory, long-term memory or attention levels.

Another similar but larger study was published more recently. People taking Bacopa had significantly better scores on a test of working memory. However, the study measured almost 20 different cognitive scores, with only one test showing a significant difference. Other measures of word recall, numerical memory and speed of recall, did not differ between the two groups. Another study involved men over 65 years who did not have any signs of dementia. Two measures of memory were significantly improved in the group taking Bacopa, as were depression and anxiety scores. However, a number of other memory and cognitive tests showed no significant differences.

Another study gave participants Bacopa along with Ginkgo balboa, another herb with a reputation for improving memory. No significant differences were found between the groups on memory tests.

PROBLEMATIC ASPECTS

In contrast with many herbal remedies, toxicity studies have been carried out with different doses of Bacopa. These found no adverse effects when given at standard doses. Some people report nausea or dry mouth when taking Bacopa.

RECOMMENDATIONS

The clinical trials to date show some encouraging results for Bacopa as a memory-enhancing remedy. Short-term use does not appear to be effective, but after about 12 weeks some benefits were found. However, the studies have an important limitation. All used several psychological tests and found significant improvements in only some of them. In most cases, the majority of the tests found no beneficial effects. In studies using multiple measurements, the probability increases of getting positive results purely by chance. Statistical adjustments can be made to take this into account, which one study acknowledged were not done. Such multiple testing reduces the level of confidence we can have in these results. Given the complexity of memory, and the variability of the results from these studies, more research is needed to provide clearer guidance on whether Bacopa has a real impact on memory.

Dónal O’Mathúna has a PhD in pharmacy, researching herbal remedies and an MA in bioethics, and is a senior lecturer in the School of Nursing, DCU