Tea and herbal teas have been historically used around the world by several cultures to raise their wellness in social meetups. The health-promoting advantages of teas have been discovered through many studies.

Research shows that individuals who drink tea frequently have better cognitive function than those who do not drink tea.1 Similarly, another study shows that individuals who drink tea for a minimum of three times a week live a healthier and more prolonged life than the individuals who do not drink tea.2 Different types of tea have various health benefits. In this paper, we will explore a few popular types of teas and their associated health benefits in the evidence of research literature.

Green Tea

Harvested from the Camellia sinensis plant, green tea leaves are filled with several antioxidant compounds that offer various health advantages.

Benefits of Taking Green Tea

• May Enhance Cognitive Function : Green tea plays an integral role in strengthening brain functionality. Research suggests that taking black tea and green tea can improve memory.3
• Helps Mitigate the Risk of Cancer : Research indicates that green tea has various antioxidant elements that assist in preventing cancer. A meta-analysis demonstrated that women who drank more than three cups of green tea per day have a reduced risk of breast cancer recurrence by as much as 27% as compared to those women who did not drink green tea. Also, case-control studies, but not cohort studies, demonstrate a reduction in initial breast cancer diagnosis by 19%.4
• May Help Prevent Type 2 Diabetes :  According to a systematic literature review of seventeen randomized controlled trials, green tea was found to significantly lower blood glucose levels, hemoglobin A1c, and fasting insulin, suggesting a favourable effect on insulin sensitivity.5
• Helps Promote Weight Loss : The effect of green tea on weight loss is to raise the body’s metabolic rate. Research suggests that green tea can help lower body fat. Specifically, it is a beverage of choice to help reduce the fat in the abdominal area.6
• Helps Prevent Viral Infections : A randomized, placebo-controlled trial among 270 health-care workers in Japan demonstrated that consumption of green tea containing catechins reduced the risk of upper respiratory infection by 50% compared to placebo.7

Black Tea

Black tea is made with oxidized leaves from Camellia sinensis and provides as well various health-promoting advantages. It contains antioxidant elements that help to alleviate inflammation in our body.

Benefit of taking Black Tea

• Acts as an Antioxidant : Black tea contains antioxidant elements such as thearubigins (the brown pigment in black tea), theaflavins, and catechins, that help improve overall health.8
• Supports Cardiovascular Health : According to the World Health Organization, “CVDs are the number 1 cause of death globally: more people died annually from CVD than from any other cause. An estimated 17.9 million people died from CVDs in 2016, representing 31% of all global deaths. Of these deaths, 85% were due to heart attacks and stroke.”9 Black tea contains antioxidant elements called flavonoids, which provide health-promoting benefits for the heart. A review showed that individuals who drink at least three cups of black tea per day have a reduced risk of developing heart disease.10 Research showed that people who drink black tea experience a significant decrease in diastolic and systolic blood pressure compared to placebo.11
• May Help Prevent the Risk of Developing Some Types of Cancer : Moreover, black tea contains polyphenols that help prevent against some types of cancer. A preclinical study demonstrated that polyphenols found in black tea may help to prevent against hormone-dependent cancers, such as breast cancer, and may help to alleviate resistance to treatment in these types of cancers.12
• Improves Gut Health : Black-tea polyphenols may also play a role in modulating the gut microbiome. A review suggested that polyphenols in black tea may help populate beneficial Lactobacillus strains and ward off harmful Salmonella and Helicobacter pylori strains.13
• Improves Concentration : Black tea contains the amino acid ʟ‑theanine, well known for its relaxing effects, as well as caffeine. These compounds have been suggested to improve brain focus and alertness.14

White Tea

As for green and black teas, white tea comes from the Camellia sinensis plant, but from the first harvest before the tea plant’s leaves fully open, when the young buds are still covered by fine white hairs, hence the name “white” tea. Research has shown that the temperature of the water and steeping time determine its antioxidant characteristics.15 Because of its delicacy, white tea must be prepared at a specific temperature, around 70 °C, to maintain its health-promoting effects and for the best taste.

Benefits of Taking White Tea

A study on the variation of composition between white and green tea suggested that “certain green and white tea types have comparable levels of catechins with potential health promoting qualities” and that “the polyphenolic content of green teas was found to be similar to certain white tea varieties.” The authors of the research paper conclude that processing, cultivation, and the source itself may influence the catechin content of white tea.16 Given these results, it is understandable that white tea may offer similar health benefits as green tea, such as:

• stimulating metabolism pathways that induce weight loss;
• preventing infection (among others, it helps protect teeth from harmful bacteria);17
• helping to prevent some cancers;
• osteoporosis prevention; and
• protecting against heart diseases due to its polyphenol compounds.

A study has shown that individuals who regularly drink a minimum of three cups of white tea per day have a 21% lower chance of suffering from heart diseases.18

Chamomile Tea

Chamomile tea is made with the dried flowering parts of a daisy-like blossom. Many people love to drink chamomile tea in place of green or black tea, due to its sweet, earthy taste. Moreover, this tea is also full of antioxidants and does not contain caffeine.

Benefits of Taking Chamomile Tea

• Improves Sleep : Chamomile contains an antioxidant called apigenin, a flavonoid that binds to the same receptors in the brain as the ones targeted by benzodiazepines, with the result of calming the nervous system and helping reduce insomnia and increase sleepiness.19 Chamomile has shown to improve sleep quality in hospitalized elderly patients,20 and for women after childbirth.21
• Improves Digestive Health : The uses recognized for chamomile by the German health authorities (Commission E) are digestive disorders and inflammation in the mouth.22 Also, in a preclinical study, it was revealed that chamomile tea has the potential to help relieve diarrhea in rats.23
• Contributes to the Prevention of Cancer

Chamomile contains apigenin, a particular type of antioxidant, that may help to lower the risk of some cancers. A study conducted in test tubes showed that apigenin antioxidants has positive effects on cancer cells, specifically those of the digestive tract, breast, uterus, skin, and prostate.24 Some other benefits found in traditional herbal medicine literature for chamomile:

• it boosts the body’s immune system;
• it is anxiolytic;
• it helps controls the blood sugar level;
• it supports cardiovascular health; and
• it is traditionally used as a topical to help relief pruritis and skin affections.

Dandelion Tea

Like chamomile, dandelion belongs to the daisy or Asteraceae family of blossom plants. Dandelion is growing in many environments globally and some people will consider it as an invasive species. Although considered a weed, it has long historical and traditional uses both for culinary and medicinal purposes.

Benefits of Taking Dandelion Tea

• Is Highly Nutritious : Dandelion tea provides several significant minerals including magnesium, iron, potassium, and calcium.25 The root, often used as an infusion, is particularly rich in potassium, fructose and inulin, a probiotic.26
• Supports Digestive and Urinary Functions : Dandelion has been traditionally used to support liver health, especially as a choleretic and cholagogue (stimulate respectively the production and circulation of the bile), as well as a digestive and a diuretic.
• Prevents Oxidative Stress : It contains several antioxidants—especially flavonoids, sterols, triterpene alcohol and sesquiterpene lactone that gives its bitter taste—that overall help protect against oxidative stress and cellular damage.27 Interestingly, data of an in vitro study aiming to investigate the anti–HIV‑1 activity of aqueous dandelion extract suggest that it has a potent inhibitory activity against HIV‑1 replication and reverse transcriptase activity.28
• 

Turmeric Tea

Turmeric (Curcuma longa) is a yellow-orange spice that is commonly used for sauces and curries and that can also be prepared as a tea. It has been used for centuries in traditional Chinese and Ayurvedic medicine for its anti-inflammatory properties, mainly due to its active compounds that also gives the rhizome its colour, curcuminoids. Hundreds of clinical trials illustrate the ongoing interest in curcumin and its applicability to a wide range of diseases including cancer; various inflammatory conditions including dermatitis, irritable bowel disease, colitis, Alzheimer’s disease, and different neurological conditions; rheumatoid arthritis; fibromyalgia; diabetes; or metabolic syndrome.29 Golden milk can be a great way to discover turmeric as a beverage and enjoy a spicy time in the heart of the winter.

Hibiscus Tea (Sour Tea)

Hibiscus tea is made by soaking fragments of the aerial parts of the hibiscus plants into boiling water. Hibiscus tea has a tart flavour like that of cranberries.

Benefits of Taking Hibiscus Tea

• May Help Reduce Blood Pressure : A systematic review study demonstrated that hibiscus tea can reduce both diastolic and systolic blood pressure by an average of 3.53 mmHg and 7.58 mmHg, respectively.30 Its phenolic compounds, anthocyanosides, and several organic acids give it spasmolytic and blood vessel protective properties. Hibiscus tea has been used in traditional medicine to help relief functional asthenia (general fatigue) and help gain weight for people with underweight symptoms.31

Not only will teas bring several health benefits, but they will also delight in the pleasure of taste.

REFERENCES

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