“Tea” has become the most popular “beverage” of our time. Beyond simply quenching thirst, tea can help with digestion, reduce greasiness, lower internal heat, improve eyesight, calm the mind, relieve stress, stimulate saliva production, and quench thirst. For those who are absolutely devoted to tea, not a single bit of tea leaf goes to waste, and perhaps savoring tea is also a spiritual pursuit. However, it's common for too much tea to be used or for it not to be fully savored, inadvertently resulting in “leftover tea.”
Do you understand “leftover tea”? Can you drink leftover tea, and what happens if you do? A series of questions might leave you feeling a bit confused. No worries, today we'll provide some insights into the “history” of leftover tea.
Can You Drink Leftover Tea?
Leftover tea is often considered undrinkable because it has been sitting for too long, causing vitamins to degrade. The proteins and sugars in tea leaves can become nutrients for harmful microorganisms, which is why people generally believe that leftover tea should not be consumed.
Tea typically remains in the body for about three hours, and even longer for strong tea, leading to an accumulation of caffeine that can cause neurological disturbances. As tea sits, it not only loses its vitamin content but can also spoil and turn sour. Tannins in the tea can oxidize into highly irritative compounds, harming the stomach and intestines, especially during summer, potentially causing gastrointestinal inflammation.
Research shows that the primary change in leftover tea is the further oxidation of polyphenols, leading to a darker color. Clear green tea will lose its green hue and become more yellow over time, particularly in warmer temperatures. This is due to the oxidation of polyphenols into yellow, red, and brown pigments, primarily theaflavins, thearubigins, and theabrownins. These products are non-toxic and do not pose a health risk to humans.
Risks of Drinking Leftover Tea
Tea contains polyphenols, which oxidize in air and water to form a brownish gel called “tea rust.” Tea rust contains elements such as cadmium, lead, iron, arsenic, and mercury. The longer unfinished tea is exposed to air, the more polyphenols oxidize into tea rust.
When tea rust enters the body, it binds with proteins, fats, and vitamins in food, precipitating and hindering nutrient absorption and digestion. These oxidized substances can cause inflammation, ulcers, and necrosis in organs like the kidneys, liver, and stomach. Therefore, leftover tea should not be consumed, and tea utensils should be cleaned regularly.
The risks mentioned are minor. Overall, Drinking Tea benefits health, and leftover tea also has its uses! The term “leftover tea” usually refers to stronger teas like Pu'er, Longjing, and Dahongpao. Doctors recommend against drinking strong tea overnight and suggest rinsing tea twice with boiling water when brewing, mainly due to potential contamination during harvesting and transportation.
For many young people who prefer lighter herbal teas like chrysanthemum, jasmine, and goji berries, drinking leftover tea does not harm the body but can actually be beneficial.
Health benefits of Leftover Tea
Cancer Prevention and Antioxidant Effects
As tea sits, it turns reddish-brown due to the oxidation of polyphenols into tea pigments. Studies show that both polyphenols and tea pigments have potent anticancer and antioxidant effects. Although leftover tea has significantly reduced vitamin C content, it still possesses disease-fighting properties.
Stopping Bleeding
Leftover tea is rich in acid, which can prevent bleeding from capillaries. For conditions like oral ulcers, tongue sores, eczema, and gum bleeding, rinsing the mouth with leftover tea can help. Wounds and skin infections can also be treated by washing them with leftover tea.
Itching Relief and Hair Growth
Washing hair or the body with warm leftover tea can quickly stop itching due to the presence of tannins, which can also help with eczema. Rinsing hair with leftover tea promotes hair growth and eliminates dandruff. To thicken sparse eyebrows, apply leftover tea with a brush daily, and over time, they will become thicker and shinier.
Teeth Health
The fluoride in tea helps strengthen tooth enamel, making it more resistant to acid attacks and reducing the risk of cavities. Fluoride also kills plaque bacteria. It's best to rinse your mouth with tea water two to three minutes after meals. Additionally, tea effectively removes bad breath due to its essential oil content, which provides a pleasant aroma. Rinsing your mouth with leftover tea before and after brushing your teeth or after meals can freshen your breath and eliminate halitosis.
Sun Protection
To treat sunburned skin, gently wipe it with a towel soaked in leftover tea. Tannins have astringent properties, and flavonoids in tea offer radiation protection.
In summary, leftover tea deserves our attention. Whether it benefits us or poses risks, we should be aware of both. Life is full of small details, and our bodies are constantly at risk. After reading this article, you should have gained deeper insights into the world of tea!