Lion’s Mane Side Effects: What the Research Shows
Bottom line: The study suggests guayusa and lion’s mane may be associated with specific cognitive improvements, but results vary and may not apply universally, with guayusa linked to increased blood pressure in some cases.
A new study shows that guayusa tea and lion’s mane extract can improve specific aspects of cognitive performance — but the effects are not the same for both, and they don’t work the way some might expect.
The Study: A Closer Look
A recent study published in Europe PMC tested the acute effects of guayusa extract and Nordic lion’s mane on cognition. The research used a randomized, double-blind, placebo-controlled, crossover design. Participants received 650 mg of guayusa extract, 1 g of Nordic-grown lion’s mane, or a placebo. They then took neuropsychological tests — Go/No-go, N-Back, and Serial 7s — at baseline and 1 and 2 hours after taking the dose.
The results showed that both guayusa and lion’s mane had significant effects on cognitive performance, but in different ways. Guayusa improved the number of attempts during Serial 7s, total score, correct responses, and reaction time during N-Back. It also improved Go stimulus reaction time. However, it reduced the percentage of correct responses in the No-go stimulus during Go/No-go. Lion’s mane, in contrast, improved the number of attempts during Serial 7s, reaction time during N-Back, and Go stimulus reaction time in Go/No-go.
Mechanisms and Comparisons
How do these substances work? And how do they stack up against other nootropics? The study suggests guayusa may have a more pronounced effect on mental clarity, focus, concentration, mood, and productivity. Lion’s mane, meanwhile, improved working memory, complex attention, and reaction time, as well as perceptions of happiness. Compared to a study on TruBrain, an over-the-counter nootropic, the results suggest natural substances like guayusa and lion’s mane may have more targeted and sustained cognitive benefits.
One unexpected result was that guayusa extract increased blood pressure compared to the placebo or lion’s mane. This raises concerns about its use in people with hypertension. Both substances did improve subjective ratings of “happiness compared to peers” and “getting the most out of everything,” though this effect was more immediate with lion’s mane.
Frequently Asked Questions
- Are guayusa and lion’s mane extracts safe to use? The study suggests they are generally well-tolerated, but people with hypertension should be cautious.
- Can guayusa and lion’s mane improve cognitive performance in people with impairments? The study only looked at healthy individuals. More research is needed for people with cognitive impairments.
- How do they compare to other nootropics? The study suggests they may have more targeted effects than some over-the-counter supplements.
- Can they be combined with other substances? The study didn’t investigate combinations, so more research is needed.
- Are there any side effects? Guayusa elevated blood pressure, which could be a concern for people with hypertension.
Sources
- ¶Acute Effects of Naturally Occurring Guayusa Tea and Nordic Lion’s Mane Extracts on Cognitive Performance
- ¶The Effects of an Over-the-Counter Nootropic on Indices of Cognitive Performance
- ¶Acute Alpha-Glycerylphosphorylcholine Supplementation Enhances Cognitive Performance in Healthy Men
Educational Disclaimer
This article is for informational and educational purposes only. It is not medical advice, mental health advice, diagnosis, treatment guidance, or a recommendation to use any substance, supplement, therapy, or protocol.
We review publicly available research and explain what the evidence may suggest. Some studies may be early-stage, observational, animal-based, lab-based, theoretical, or incomplete. Always consult a qualified professional before making health-related decisions.
Researched and drafted by Spore, ShroomWire’s AI research assistant, and reviewed by the ShroomWire editorial team before publishing.
