Drinking black tea has been known to provide mental health benefits, but what about inhaling its aroma? Research has found that inhaling the aroma of black tea may reduce stress levels before and after a mentally stressful event. In the study, which was published in the Journal of Physiological Anthropology, the relieving effects of two kinds of black tea (Assam and Darjeeling) aromas on physical and psychological stress were evaluated.
A team of researchers at the University of Shizuoka, Chubu University, Mitsui Norin Co., Ltd, and Tokai University in Japan recruited 18 healthy people aged between 20 and 21 years to participate in the study. The research team instructed the participants to not consume anything except water for three hours before the start of every trial.
Then, the team induced stress in the participants using a psycho-diagnostic test called Uchida-Kraepelin test. This test involves mathematical problems to be solved within 30 minutes, split into two 15-minute sessions. In between sessions, the participants were tasked to inhale either black tea aroma or be exposed to warm water for one minute.
After these, the research team used levels of salivary chromogranin-A (CgA), an acidic protein produced in response to stress, as a stress marker to identify the effect of inhaling black tea aroma in the participants.
Based on the results, participants who inhaled black tea aroma exhibited lower salivary CgA concentration levels after 30 minutes of mentally stressful tasks, in comparison to those who were exposed only to warm water.
In addition, both black teas caused similar effects, even though Darjeeling tea aroma has a higher concentration of anti-stress components, such as hexanal, hexanol, and linalool, compared to Assam black tea. Hexanal and hexanol have been previously reported to decrease mental stress response in mice, while linalool possesses sedative effects.
“The above results indicated that inhaling black tea aroma may diminish stress levels caused by arithmetic mental stress tasks, and Darjeeling tea aroma tended to improve (the) mood before mental stress load,” wrote the research team.
Black tea preparation and its other health benefits
Black tea may be the most common among the three main varieties of tea, including green and oolong. Although all teas come from the same plant, each variety is processed differently. The evergreen shoots of black tea are firstly picked, then withered, rolled, fermented, and dried.
Preparing black tea
- With the use of a muslin pouch, put 1 teaspoon of black tea per 1 cup of hot water.
- Leave the tea to steep for four to eight minutes for the tea to have enough time to release most of the soothing tannins.
- Add some lemon juice to the tea if you are going to use it as a remedy for cold.
Benefits of black tea
- Black tea relieves diarrhea: Most of the beneficial effects of black tea can be attributed primarily to its tannins, which provide a soothing effect on the mind and body. These tannins help relieve diarrhea by reducing intestinal activity and exerting an anti-diarrheal effect. When using black tea as a diarrhea remedy, let it steep for 15 minutes to release more of its tannins.
- Black tea enhances concentration: The caffeine content of black tea is responsible for enhancing mental focus and concentration. Drinking three cups of black tea each day every morning can increase one’s mental performance. (Related: A Cup of Black Tea Each Day Reduces Risk of Parkinson’s Disease by Astonishing 71 Percent.)
- Black tea reduces cholesterol levels: Black tea contains theophylline, which may improve cholesterol levels. To lower low-density lipoprotein (LDL) cholesterol levels, consume two cups of black tea daily for three weeks.