A recent study conducted in Japan has unveiled an intriguing dimension to sushi beyond its well-known combination of fish and seaweed. Researchers from Tohoku University have discovered that wasabi, that zesty green condiment traditionally paired with sushi, can significantly enhance both short-term and long-term memory.
According to Rui Nouchi, the study’s lead researcher and an associate professor at the university’s Institute of Development, Aging, and Cancer, the outcomes, though derived from a relatively small sample of subjects devoid of preexisting health issues, exceeded their initial expectations.
“We knew from earlier animal studies that wasabi conferred health benefits,” Nouchi said during an interview conducted in northeastern Japan. “But what really surprised us was the dramatic change. The improvement was really substantial.”
The principal active constituent within Japanese wasabi is a biochemical compound named 6-MSITC, recognized for its antioxidant and anti-inflammatory properties, a rarity in the plant kingdom, as noted by Nouchi.
The research, executed as a double-blind, randomized study, featured 72 healthy participants aged between 60 and 80. Half of the participants were administered 100 milligrams of wasabi extract at bedtime, while the remaining half received a placebo.
After three months, the group treated with wasabi extract demonstrated significant enhancements in two aspects of cognitive function: working (short-term) memory and the more enduring episodic memory. These improvements were gauged through standardized assessments of language skills, concentration, and the ability to perform simple tasks.
However, there was no observable improvement in other cognitive domains, including inhibitory control (the capacity to maintain focus), executive function, or processing speed.
The subjects who received the wasabi treatment exhibited an average 18 percent surge in their episodic memory scores, with an overall average score 14 percent higher than the placebo group.
The researchers postulated that 6-MSITC may contribute to a reduction in inflammation and oxidative stress levels within the hippocampus, the region of the brain responsible for memory functions, thereby promoting neural plasticity.
In comparison to the control group, the study reported that individuals who were administered wasabi “showed improved verbal episodic memory performance as well as better performance in associating faces and names, which is often the major memory-related problem in older adults.”
Wasabi belongs to the mustard family of plants, and the piquant paste derived from it garnered esteem in Japan centuries ago due to its antimicrobial properties, making it effective in combating foodborne pathogens such as E-coli and staphylococcus. Furthermore, its distinctive flavor and aroma make it an ideal complement to seafood.
Rui Nouchi, a specialist in dementia prevention, turned to wasabi as a treatment option after experiencing high dropout rates with conventional methods for preserving cognitive health, such as the Mediterranean diet, exercise regimens, and music therapy.
Nouchi reasoned that a daily supplement would be more sustainable, particularly for older adults, while delivering greater benefits than other anti-inflammatory and antioxidant spices like ginger and turmeric.
The Tohoku University research team now has plans to extend their investigations to include individuals from various age groups and explore whether wasabi could potentially slow down cognitive decline in dementia patients.
However, there is a significant caveat to these findings: the piquant paste served at nearly all sushi establishments, even in Japan, is almost certainly an imposter. What is far more prevalent is a convincing imitation, typically composed of ordinary white horseradish dyed green.
Authentic wasabi, indigenous to Japan, is notoriously challenging to cultivate. The plant necessitates nearly two years to mature and demands precise conditions involving temperature, shade, gravel composition, and water quality. Astonishingly, its production cost per pound can even surpass that of the finest-grade tuna it often accompanies.
Genuine wasabi must be consumed fresh, with the rough rhizome or stem of the plant grated tableside just before consumption. On a positive note, even a small serving of genuine wasabi offers equivalent benefits to the capsule supplements employed in the Tohoku study, delivering 0.8 milligrams of 6-MSITC.
The study is published in the journal Nutrients.
—–
Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.
—–
Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.