Exploring the Memory-Boosting Potential of Wasabi: Study

Wasabi, is a popular spicy condiment often served with sushi. The wild plant growing in mountains might help healthy older adults who don't have any cognitive issues improve their memory, a small Japanese study suggests.

Scientists focused on the main bioactive compound in wasabi, 6-MSITC (6 methylsulfinyl hexyl isothiocyanate), which has long been thought to have antioxidant and anti-inflammatory properties with the potential to improve cognitive function, according to study results published in the journal Nutrients.

Researchers randomly assigned 72 healthy adults ranging in age from 60 to 80 years old to take a capsule containing 6-MSITC or a placebo at bedtime for three months. All of the participants completed cognitive testing at the start of the trial and again three months later.

By the end of the study, people taking wasabi supplements showed significant improvements in working memory, which involves short-term recall, as well as in what’s known as episodic memory, or the ability to remember past personal experiences.

While the exact reasons for these memory improvements in cognitively healthy older adults aren’t clear from the study, it’s possible that the antioxidant and anti-inflammatory properties of wasabi may play a role because this has been seen before in animal studies, says Takakazu Oka MD, PhD, a professor and director of the department of psychosomatic medicine at the International University of Health and Welfare in Japan.

“Similar effects may contribute to the improvement of working and episodic memory in humans,” says Dr. Oka, who has researched the health effects of wasabi but wasn’t involved in the new study.

Participants in the treatment group took capsules containing 100 milligrams (mg) of wasabi extract powder, which had 0.8 mg of 6-MSITC. The study looked at other aspects of cognitive function such as focus and executive function, but didn’t find any benefits to the wasabi supplements beyond its impact on memory.

“This could be due to the overall age of the participants-they are not that old and therefore overall cognitive function is probably pretty good,” says Marloes Dekker Nitert, PhD, an associate professor in the School of Chemistry and Molecular Biosciences at the University of Queensland in Australia, who wasn’t involved in the new study.

However more research is needed in people who already have cognitive challenges to see if wasabi might help slow or stop declines in brain function as people age, Dr. Nitert adds.

Where you eat wasabi matters, too. The wasabi plant is native to Japan, and forms of this condiment served in the United States are often made from horseradish that’s dyed green and mixed with other ingredients.

It’s not clear if supplements containing other ingredients or different amounts of the bioactive compound in real wasabi-or the imitation wasabi paste typically served with sushi in the United States-would have the same impact on brain function as the supplements used in the study.

“It would depend on how much wasabi you put on your sushi, whether the other ingredients in the wasabi mixture affect 6-MSITC at all, and of course how often you eat sushi or wasabi in other forms,” Nitert says. “Also, not all wasabi supplements are equal.”

Reference:

Nouchi, R.; Kawata, N.Y.S.; Saito, T.; Nouchi, H.; Kawashima, R. Benefits of Wasabi Supplements with 6-MSITC (6-Methylsulfinyl Hexyl Isothiocyanate) on Memory Functioning in Healthy Adults Aged 60 Years and Older: Evidence from a Double-Blinded Randomized Controlled Trial. Nutrients 2023, 15, 4608. https://doi.org/10.3390/nu15214608.