Green Tea’s Effects on Brain Signaling

Green tea contains compounds that have been shown in animal and cell studies to defend brain function.^1,2

A meta-analysis of 36 observational studies found that green tea consumption was associated with lower rates of cognitive issues and dementia compared to those who rarely drink it.³

Another meta-analysis with nearly 50,000 subjects found the rate of cognitive disorders to be 35% lower in regular green tea drinkers.⁴

Randomized controlled trials have shown that consuming green tea powder enhanced cognitive function in young⁵ and elderly humans.⁶

Green Tea Nutrients

Diet can play a major role in susceptibility to age-related cognitive decline and risk for dementia.^7,8

From preclinical to clinical studies, scientists have identified beneficial effects of green tea and its nutrients for the nervous system.^1,2,9

Green tea, is rapidly dried after picking, which enables it to have high concentrations of polyphenols known as catechins.^10,11

In studies that look at various types of tea consumption, the greatest benefits to brain health have been seen with green tea.^4,12

Brain and Body Health

The catechins in green tea function as antioxidants and anti-inflammatories.^13,14 They help reduce major drivers of age-related chronic disease.

That may explain, in part, why the nutrients in green tea have been shown to increase lifespan in several animal species, including roundworms,^15,16 fruit flies,¹⁷ and mice.¹⁸

One preclinical study demonstrated that green tea has additional properties that appear particularly beneficial for the brain, including boosting the creation of new brain cells and improving the brain's ability to adapt into old age.¹⁹

Two of the most unique ways green tea boosts brain health is through its interactions with the gut and its enhancement of brain signaling.

Improving Gut and Brain Health

The relationship between gut health and brain health is a close one. Signals sent back and forth between the gut and the brain have a profound impact on aging and risk for disease.¹

Intake of green tea helps to ensure a healthy gut by:¹

• Improving the diversity of bacteria in the gut. Tea polyphenols have been shown to boost the number of beneficial microorganisms while inhibiting the growth of some potentially harmful strains of bacteria.
• Protecting the lining of the intestines. This helps avoid "leaky gut," which may contribute to the neuroinflammation that drives diseases like Alzheimer's and Parkinson's.

Boosting Brain Signaling

Neurotrophic factors are signaling compounds produced in the body that are required to support the optimal health and function of nerve cells.²⁰

Neurotrophic factor stimulation helps the brain ward off degenerative disease and fine-tune brain cell function.²⁰

The activity of these neurotrophic factors tends to dwindle with age²¹ and contribute to neurodegeneration.^20-22

The catechins in green tea have been shown to enhance neurotrophic factor activity.¹ They do this by:

• Increasing the production of neurotrophic factors, and
• Enhancing the function of the receptors on brain cells that receive signals from them.

Human Studies

Numerous large population studies of green tea's brain benefits have been performed, following hundreds of thousands of people.

They consistently find that those who consume the most green tea have significantly better cognitive performance and lower rates of neurodegenerative disorders than those who consume the least.^4,12,23-36

These include lower rates of mild cognitive impairment and dementia.

Summary

Green tea is a source of beneficial compounds known as catechins.

In studies, green tea and catechins have been shown to protect the brain into older age.

Large observational studies of green tea consumption consistently demonstrate that those who consume the most have the lowest rates of cognitive impairment, Alzheimer's, and other forms of dementia.

Placebo-controlled trials show that consuming green tea powder boosts cognitive function in old and young human subjects.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

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