“Sometimes, all you need is a cup of tea.”

Since tea is the second most popular beverage in the world (sorry, coffee lovers) after water, you’ve probably either tried tea or know about it to some extent.

Perhaps you’ve tried white tea to soothe you in stressful times. Maybe your go-to is an Earl Gray tea with a teaspoon of milk and some honey. At the very least, you’ve tried green tea or its powder version, Matcha.

There are certainly many options to choose from when it comes to tea – but what does science say about the benefits of this beloved ancestral tradition?

To understand the science behind tea, we must return to the basics: What is tea? Tea, simply put, is pouring hot water over different parts of the Camellia Sinensis plant.

Tea was known to be a medicinal beverage for its myriad benefits in China in the third century AD. However, Great Britain popularized this beverage through their staple tradition coined “afternoon tea.”

We spoke to Umadevi Naidoo, MD, a Massachusetts General Hospital physician-scientist within the newly emerging field of nutritional psychiatry – the study of how food impacts our mental health – to learn more about the benefits of tea, according to science.

Naidoo founded the Nutritional Psychiatry program at Mass General and is currently the only nutritional psychiatrist at MGH.

By conducting research in the field at the local and national levels, she hopes to raise awareness and increase access to care.

In addition to her role as a clinician and investigator, Naidoo has completed savory and pastry classes at Le Cordon Bleu in Paris and the Culinary Institute of America.

She then went on to pursue a degree as a professional chef at the Cambridge School of Culinary Arts in Massachusetts.  

Is there a direct involvement between tea and brain functioning?

“Tea is naturally rich in many plant compounds that support brain function and well-being, including antioxidants, amino acids and sometimes caffeine,” says Naidoo. “These compounds reduce inflammation in the brain, which can cause cognitive fatigue and brain fog. Tea consumption is therefore associated with increased focus, energy and mood.”

Are there differences in the benefits of drinking tea vs. a tisane (or herbal tea)? 

“Tisane is a category of herbal beverage made from steeping items like flowers, herbs, and barks, while teas are made specifically from the leaves of the Camellia Sinensis plant. The main difference between these two beverages is that teas all contain caffeine, while tisanes are naturally caffeine free. Therefore, teas tend to be more energizing, while tisanes promote calmer feelings.”

What tea has been shown to have the most favorable benefits for improving brain function? 

“One of my favorite teas for brain health is green tea. It is incredibly rich in polyphenols and catechin called epigallocatechin-3-gallate (EGCG),” Naidoo says. “EGCG has powerful anti-inflammatory properties that can reduce the risk of neurodegenerative diseases with age. Green tea is also rich in the amino acid L-theanine, which has been shown to reduce stress and anxiety levels.”

Tea is a beverage high in antioxidants. Can you expand on why this makes it comparable to the benefits of drinking coffee without compromising the amount of caffeine? 

“Tea and coffee are beverages both made from plants, so their nutrient profiles and antioxidant properties are unique to the plants from which they’re made. But both beverages are notably rich in polyphenols, a specific type of antioxidant compound that can fight a variety of chronic illnesses. Coffee contains more caffeine than tea so many people opt for tea when they’re looking for the health benefits of antioxidants without as much stimulation as coffee provides.”

Can you please expand on what health benefits we receive from regular consumption of polyphenols? How does it impact our brain? 

“Polyphenols help the body fight the effects of oxidative stress, which causes chronic inflammation in the body and mind. Chronic inflammation has been tied to stress, anxiety, depression, brain fog and cognitive decline with age. Regularly consuming polyphenols helps reduce inflammation, maintain healthy brain tissue, and promotes mental fitness and emotional wellbeing.”

About the Mass General Research Institute
Research at Massachusetts General Hospital is interwoven through more than 30 different departments, centers and institutes. Our research includes fundamental, lab-based science; clinical trials to test new drugs, devices and diagnostic tools; and community and population-based research to improve health outcomes across populations and eliminate disparities in care.
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