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The secret to a sharper mind, quicker thinking, and better memory could be sitting quietly in your breakfast bowl. Scientists in the UK just uncovered a remarkable connection between a simple morning snack and improved brain function within hours of eating it.
Key Takeaways
- Fast-Acting Brain Boost: Consuming walnuts improved reaction time and memory as soon as six hours after eating them.
- Unique Nutrient Profile: Walnuts contain more ALA (omega-3) than any other nut and are rich in cognitive-supportive compounds like flavonoids and peptides.
- Brain-Friendly Breakfast: EEG scans and blood tests confirm walnuts enhance neural activity and may improve cognitive efficiency during mentally demanding tasks.
The Brain-Boosting Food That Works Faster Than You Think
It’s divided into two halves, has folds and wrinkles, and its shape closely resembles a human brain. Nature supplies plenty of clues to decipher what this crunchy treat is good for, so if you’re not already snacking on walnuts, it’s time to get started. That’s right, while all nut varieties are nutritious, walnuts come out on top when it comes to brain health.
They improve working memory, slow brain aging, and protect against cognitive decline. They also improve processing speed, cognitive flexibility, and increase memory and learning skills.
A 2021 review by researchers at Tufts University concluded that “the existing evidence…suggests that walnut intake may have a beneficial effect on cognition-related outcomes, including cognitive function, mood, and stroke.”1
Cognitive benefits are seen in people of all ages after two to six months’ consumption. But can they also be seen in the hours following their consumption? This would be valuable to know, especially if taking an exam, solving a cryptic crossword, or playing a brain-taxing chess game.
Since no such short-term study had ever been conducted, researchers at the University of Reading, England, devised their own trial.2
Walnuts Speed Reaction Time
Researchers recruited 32 young adults – all healthy and between 18 and 30 years old – to see exactly what happens in our brains after eating walnuts. They didn't just ask participants how they felt; they measured it scientifically with blood tests and by monitoring electrical brain activity using EEG while participants completed mental challenges.
The study design was clever. First, they split everyone into two groups. One group enjoyed a breakfast that included about two ounces of crushed walnuts mixed into muesli with vanilla yogurt. The other group ate a nearly identical breakfast without the walnuts, but carefully balanced to have the same calories and nutrients. The genius part? A week later, they switched the groups and repeated everything so each person served as their own control.
Scientists continued testing participants at 2, 4, and 6 hours after breakfast to track changes throughout the day. The results were eye-opening. People performed noticeably better in two ways after eating the walnut breakfast:
- Their reaction times were faster consistently throughout the day
- Their memory performance improved, especially later in the day when we typically experience mental fatigue
When researchers examined the EEG readings, they found something particularly interesting—the walnut breakfast appeared to help brains work more efficiently during difficult mental tasks. Blood tests revealed positive changes in glucose and fatty acid levels, which could explain the brain performance boost.
Researchers Say: Walnuts May Be a Shortcut to Sharper Thinking
Professor Claire Williams, who led the research, said: “This study helps strengthen the case for walnuts as brain food. A handful of walnuts with breakfast could give young adults a mental edge when they need to perform at the top of their game. It's particularly exciting that such a simple dietary addition could make a measurable difference to cognitive performance."
Professor Williams and her colleagues noted several reasons walnuts are so good for the brain.
- Supports new brain cells by boosting BDNF: In their paper published in Food and Function in March, the researchers reported on previous findings showing a direct brain benefit from increased levels of brain-derived neurotrophic factor (BDNF), which is important for creating new neurons and strengthening connections between them.3
- Provide more ALA than any other nut to support brain function: Unlike almost all other nuts, which contain trace amounts of ALA, walnuts contain 5.5 grams per 100 grams (and more omega-6 fatty acids than any other nut at 28 grams per 100 grams).
- Supply protein and antioxidant flavonoids for better brain health: These nutrients help benefit the brain indirectly by helping reduce blood pressure, lowering LDL cholesterol, dampening post-meal glucose spikes, and improving gut microbiome diversity.
For those looking to optimize mental performance, incorporating walnuts into your breakfast might be one of the simplest brain-boosting strategies available. Rather than turning to stimulants, this research suggests that some of the most effective cognitive enhancers might be found in whole foods that humans have consumed for thousands of years.
Whether you're a student preparing for exams, a professional with demanding cognitive tasks, or simply someone interested in maintaining brain health, this study offers practical, evidence-based guidance that's accessible to almost everyone. Future research will likely explore whether these benefits extend to other age groups and whether longer-term walnut consumption might provide cumulative cognitive advantages over time.
Summary
New research shows that eating walnuts at breakfast can lead to faster reaction times and improved memory performance throughout the day. A study conducted at the University of Reading found that just two ounces of walnuts mixed into breakfast improved brain activity, boosted memory, and led to measurable changes in blood glucose and fatty acid profiles — all indicators of enhanced cognitive function. Packed with ALA omega-3s, flavonoids, and peptides, walnuts stand out among nuts for their ability to support short-term and long-term brain health.
Frequently Asked Questions
What makes walnuts good for the brain?
Walnuts are rich in alpha-linolenic acid (ALA), a plant-based omega-3, along with peptides and flavonoids that promote neurogenesis and reduce inflammation.
How quickly do walnuts impact brain function?
In the study, cognitive improvements were measurable within 2 to 6 hours after consumption.
How many walnuts should I eat for brain benefits?
About 2 ounces (roughly a handful or 14 walnut halves) was the amount used in the study for optimal short-term effects.
Do walnuts only help young adults?
While the study was conducted on young adults, other research suggests long-term brain benefits across all age groups.
Can I just take walnut oil or a supplement?
Whole walnuts provide a unique combination of fats, proteins, and polyphenols that likely work synergistically, so the full nut is preferred.
- 1 Cahoon D. et al. Walnut intake, cognitive outcomes and risk factors: a systematic review and meta-analysis. Ann Med. 2021 Dec;53(1):971–997.
- 2 University of Reading. Eating walnuts for breakfast could improve brain function throughout the day for young adults, a new study has shown. 20 February 2025.
- 3 Bell L, et al. The impact of a walnut-rich breakfast on cognitive performance and brain activity throughout the day in healthy young adults: a crossover intervention trial. Food Funct. 2025 Mar 3;16(5):1696–1707.
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