Green tea is thought to have many benefits, particularly in cognitive function. In 2012-14, FRAXA Research Foundation funded a clinical trial to assess the effects of EGCG (green tea extract) on cognitive function in adults with FXS. Drs. Rafael de la Torre and Mara Dierssen Sotos, principal researchers in Barcelona, Spain, reported many positive results, including:
- Increased visual, immediate, and episodic memory
- Beneficial effects on mental speed
- Positive effects on adaptive behavior (small improvement in everyday life competence)
- Increased attention
- Significant benefits in quality of life perception
- Reduced disruptive behaviors
After the extract was no longer administered, effects remained stable. Memory, attention, and mental flexibility improvements were still observable at least 3 months after treatment ended. This is somewhat suspicious for a placebo effect because usually there is a change when a drug is discontinued. We have seen that placebo effects are a huge factor in Fragile X clinical trials.
Clinical Trial of EGCG for Fragile X Syndrome
31 adults with Fragile X Syndrome, aged 18 to 55 years were enrolled in the clinical trial. They were randomly assigned to two treatment conditions: EGCG and placebo. Both treatment conditions were combined with cognitive training.
Participants all underwent one month of placebo treatment along with cognitive training. The EGCG group then had three months of treatment, followed by three months with no treatment (cognitive training continued). The placebo group continued the placebo throughout the trial.
One main issue that researchers faced was that very few participants took part in the cognitive training to a satisfactory level. There is potential for future research into making cognitive training programs more appealing or rewarding. This trial and many others have shown that increased cognitive training leads to more positive results over time.
How EGCG Works
EGCG is a type of estrogen found in plants. In humans it can have weak estrogen effects in the brain, protecting nerves from overstimulation. In particular, it has been shown to reduce the impact of proteins that are overactive in individuals with Fragile X. Therefore, ECGC may be a promising treatment to promote positive brain function in people with FXS. Further study is certainly required to replicate the results of this small trial.
Prospects for EGCG to Treat Fragile X
Although this small clinical trial suggests encouraging results, the actual data has not yet been published by the investigators yet. However, this team has just launched a new clinical trial of EGCG for children with either Fragile X or Down syndrome in Barcelona, Spain. Other studies of EGCG to treat other disorders, including Down syndrome, Parkinson’s disease, and Alzheimer’s disease, are also ongoing. So we can look forward to learning more about the potential of this supplement.
Hannah is a student of human biology at the University of Birmingham, UK. She has worked for several years with children with autism and other special needs. She writes for FRAXA Research Foundation because she believes it is really important for families to have access to advice and information about their child, and is delighted to be a part of the organization that is working so hard to provide this.