Guayusa tea and lion’s mane could improve cognitive function

Supplements derived from the fungus known as lion’s mane and guayusa tea could help improve mood and cognitive function. These substances, usually consumed as a tea or supplement, are believed to have antioxidant and anti-inflammatory properties, along with other health benefits. A new study suggests they might also enhance mood and cognitive function.
Guayusa, from the tree Ilex guayusa, is widely grown in South America and has been consumed as tea in the western Amazon for centuries. It contains polyphenols and alkaloids, including caffeine. Potential health benefits of guayusa include antioxidant activity, anti-inflammatory effects, cardiovascular protection, and neuroprotective activity.
Lion’s mane is a white, spherical mushroom (Hericium erinaceus) used in Asia for culinary and medicinal purposes. It is available as a supplement in various forms, including capsules, liquid, tablets, or powder. Studies have suggested benefits like supporting immune function, relieving anxiety and depression, lowering cholesterol, and cognitive benefits.
The new study, published in the journal Nutrients, suggests that both supplements may enhance mood and cognition in people. Kelsey Costa, a registered dietitian, commented on the study, noting the need for cautious optimism due to the study’s limited size and potential bias from the funding source, Applied Food Sciences Inc.
The study involved 40 participants, aged 18 to 50, who were habitual consumers of caffeine. They underwent health assessments and neuropsychological tests. For 24 hours before each test visit, participants followed the same diet and avoided exercise, alcohol, and caffeine. During the test visits, they received placebo, 650 mg guayusa extract, or 1 gram of Nordic-grown lion’s mane.
Results showed that both supplements improved reaction time, mental clarity, focus, concentration, mood, and productivity. Lion’s mane also improved subjective ratings of happiness. However, guayusa did raise blood pressure within the normal range for healthy individuals.
Prof. Maryann Amirshahi explained that guayusa contains caffeine and antioxidants, which could boost cognitive performance. She cautioned about the study’s limitations, including the short duration of observed effects and uncertainty about long-term effectiveness and safety.
Costa noted that caffeine in guayusa boosts alertness, while compounds in lion’s mane, such as hericinones and L-ergothioneine, may improve memory and attentiveness. The study suggests further research using EEG and/or fMRI data to gain more insight.
Both experts advise treating supplements with caution. Prof. Amirshahi emphasized that supplements, though generally safe, do not undergo the rigorous testing that FDA-approved medications do. Costa recommended consulting a healthcare professional before starting any new supplement regimen.
—Katharine Lang