This Antioxidant “Wakes Up The Brain” Similar To Exercise & It Has A Surprising Reason Why
You know that slightly bitter, mouth-drying sensation you get from dark chocolate, a bold cup of tea, or a glass of red wine? That astringent taste comes from compounds called flavanols, and according to new research, it might be doing more than just waking up your taste buds.
A preclinical study published in Current Research in Food Science1 suggests that the astringent sensation caused by flavanols could act as a direct signal to the brain, triggering effects similar to a mild workout for the nervous system. And while it's early research, it sheds light on a surprising reason why certain foods and drinks trigger physiological effects.
A note on the study
Researchers dive into the flavanol puzzle
Flavanols are subtype of polyphenols, which are plant-based micronutrients with potent antioxidant and anti-inflammatory properties.
For years, flavanols have been studied for their ability to support cardiovascular health, improve blood flow2, and protect cells from oxidative stress. Research has also linked higher flavanol intake with better cognitive performance and healthier brain aging, making them a frequent focus in longevity-minded nutrition conversations.
However, research also indicates that only a small portion of what people consume actually makes it into the bloodstream after digestion. This raises an important question: if so little is absorbed, where does the profound impact stem from? This is a question that's puzzled scientists for years.
Researchers at Japan's Shibaura Institute of Technology wanted to understand just that: Why do flavanols seem to benefit brain function when they're poorly absorbed into the bloodstream?
To investigate, they gave 10-week-old mice oral doses of flavanols (either 25 or 50 mg/kg body weight) and observed what happened.
What the researchers found
The mice that received flavanols showed:
- Increased physical activity and exploration behavior
- Improved learning and memory performance
- Activation of the locus coeruleus-noradrenaline system—essentially the brain's "alertness center"
The flavanols appeared to trigger a cascade of neurotransmitters, boosting dopamine, norepinephrine, and activating stress-response pathways.
In other words, the mice's brains responded as if they'd gotten a mini workout from the flavanols alone.
The "sensory nutrition" connection
This is where the research gets really fascinating. The team's findings suggest that it's not about flavanols getting absorbed into the blood and traveling to the brain.
Instead, the taste itself may be the trigger.
That astringent, mouth-puckering sensation appears to send signals directly to the brain via sensory nerves—a concept the researchers call "sensory nutrition." It's a paradigm shift in how we think about the relationship between taste and health benefits, indicating that it's not just a food's nutrient profile that offer benefits, but also the sensory experience of eating it.
As the researchers explained, this offers an exciting new theory for why flavanol-rich foods have been linked to cognitive benefits even though these compounds don't easily cross into the bloodstream.
Important caveats to consider
While interesting, there are a few important notes about the study to keep in mind:
- This was a mouse study, not human research. While preclinical studies are helpful, we don't yet know if the same mechanisms occur in our brains.
- The doses were controlled and specific. But translating mouse doses to human equivalents isn't straightforward.
- More research is needed before making dietary recommendations based on this specific mechanism.
While the findings are promising, human trials will be essential to confirm whether our brains respond the same way.
The takeaway
What does this mean for your morning tea or evening glass of red wine? It's too early to change your diet based on this study alone—but it adds to the growing body of evidence that flavanol-rich foods (think dark chocolate, berries, red wine, and tea) may support brain health.
And it offers a compelling new theory for how: The sensory experience of eating flavanols may be part of the benefit itself.
In other words, nutrition might not be solely about what gets absorbed into the bloodstream. The simple act of tasting certain compounds could prime the brain, activate alertness pathways, and shape physiological responses in real time. It suggests that flavor, texture, and even that slightly drying sensation could play a meaningful role in how the body responds to what we eat.