New Tea Research Boasts Heart, Brain, and Immune Benefits

When it comes to health benefits, new research suggests tea could be more than just a pleasant drink we reach for when we get a tickle in our throat.

According to data presented at the Sixth International Scientific Symposium on Tea and Human Health, drinking more true tea, specifically, may offer cognitive function support, cardiovascular health benefits, and more.

The symposium shared the latest research on the relationship between certain health aspects and tea consumption. It was held virtually on April 26, 2022, hosted by the Tea Council of the USA, and co-sponsored by professional organizations including the American Cancer Society and the Oregon State University Linus Pauling Institute.

What Is True Tea?

The research was focused on true teas. All true teas come from the same plant: a warm-weather evergreen named Camellia sinensis.

There are five types of true tea: black, green, oolong, dark, and white. How they differ is in the various degrees of processing and the level of oxidization each tea has. 

True teas contain naturally occurring compounds with antioxidant properties called flavonoids. They also contain L-theanine, an amino acid that’s been linked to cognitive benefits.

Popular herbal teas, like chamomile and mint, do not fall under the “true tea” umbrella.

How Can Drinking True Teas Benefit Overall Health?

The symposium’s presenters, which consisted of researchers and leaders in academia, reported on evidence suggesting that components in true teas are linked to many positive outcomes.

Among the findings that were presented, the cognitive, cardiovascular, and immune health benefits of true teas appeared to have the most supporting data.

Cognitive Benefits

More than 16 million people in the United States live with cognitive impairment, which can have a profoundly negative impact on a person’s quality of life. As such, cognitive function—or “brain health”—is a key area of interest.

A proactive approach to keeping our brains healthy as we age includes taking steps to support cognitive health, like maintaining our blood pressure, staying socially connected, and being physically active.

According to the researchers, the data on drinking true tea and experiencing positive brain health outcomes is promising. 

Louise Dye, PhD, a professor of nutrition and behavior at the University of Leeds and a presenter at the symposium, shared data highlighting the effects of true tea and its components on cognitive function.

Key findings from her research include:

• Randomized control trials show tea consumption offers short-term benefits for attention spans.
• Studies consistently show the beneficial effects of a high dose of L-theanine, together with a lower dose of caffeine, on attention task performance.
• Tea is beneficial during moments of stress.
  

Dye said that “when experiencing elevated stress or burnout, tea is an optimal beverage of choice due to its beneficial effects on attention.”

Jonathan Hodgson, PhD, a professor at the Institute for Nutrition Research at Edith Cowan University and another presenter at the symposium, stated that an estimated that 40% to 50% of dementia cases could be prevented through changes in diet and other lifestyle factors.

One dietary change Hodgson suggested is drinking true tea, citing growing evidence that having just a cup or two of tea a day could help reduce the risk of vascular dementia and Alzheimer’s disease.

Heart Benefits

Cardiovascular disease is the leading cause of death for both men and women in the United States.

According to information presented at the symposium, the simple act of drinking true tea may help support heart health by helping people reduce their risk of developing cardiovascular disease.

Taylor Wallace, PhD, CFS, FACN, a professor in the Department of Nutrition and Food Studies at George Mason University and a presenter at the symposium, said that “tea is the major source of flavonoids (and flavan-3-ols) in the diet.”

According to Wallace, “American tea drinkers have been shown to have 20 times higher flavonoid intakes compared to those who do not consume tea.”

Based on studies using a variety of scientific research designs, Wallace reported that having two cups of unsweetened tea per day has the potential to reduce the risk of cardiometabolic disease.

Specifically, each cup of daily tea consumption appears to be associated with an average:

• 1.5% lower risk of dying from any cause (all-cause mortality)
• 4% lower risk of dying from cardiovascular disease (cardiovascular disease mortality)
• 2% lower risk of cardiovascular events
• 4% lower risk of stroke events
  

Immune Benefits

Tea is a go-to beverage when you’re sick, but the research presented at the symposium suggests that drinking tea may even give your immune system a boost.

Dayong Wu, MD, PhD, associate lead of the Nutritional Immunology Team at the USDA Human Nutrition Research Center on Aging and associate professor at the Friedman School of Nutrition Science and Policy, Tufts University, said that “as a tasty, inexpensive beverage, tea consumption may bring certain benefits in a broad array of metabolic and immune health aspects.” 

During the symposium, Wu explained that phytochemicals in green tea called catechins have been shown to help a host fight pathogens by decreasing the germ’s ability to infect the host as well as help the host’s immune system spring into action.

Wu added that these potential effects of green tea might be related to a few different mechanisms, including:

• Antiviral effect (e.g., by inhibiting viral absorption, penetration, membrane fusion, and replication in the upper respiratory tract)
• Anti-inflammatory and anti-oxidative effects (e.g., by reducing tissue damage)
  

How to Add Tea to Your Diet

Some people are already in the habit of sipping tea throughout the day, while others just have it on occasion. If you’re in the latter camp, making tea a regular part of your routine could support your wellness.

Here are a few ways to add tea to your day:

• Make a pitcher of iced tea. Steep tea bags in boiling water with a 1:1 ratio of tea bags to water. Once brewed, serve over ice and store leftovers in the refrigerator
• Start your day by having a cup of black tea with breakfast
• Swap out your evening cocktail with a cup of soothing white tea. Have it in your favorite mug for a nightly unwinding ritual
• Make a tea latte instead of one with coffee
• Brew sun-brewed tea. Let tea bags steep in water that you place in direct sunlight, like by a window