Types of Teas and Their Health Benefits

From green tea to hibiscus, from white tea to chamomile, teas are chock full of flavonoids and other healthy goodies.

Tea is the most popular beverage in the world after water. It’s a simple preparation of pouring hot water over cured leaves of the Camellia sinensis plant. The first recording of tea described it as a medicinal beverage in China in the 3rdcentury AD. Merchants helped its popularity to spread quickly across continents. In the early 19th century, Great Britain popularized the concept of afternoon tea, a break from one’s routine in which tea is served alongside sandwiches and baked goods such as scones. The flavor of tea varies by where the tea leaves are harvested and how they are grown and processed. Black tea is the most popular worldwide, followed by green, oolong, and white tea. [1]

Herbal teas are not made from the Camellia plant but from dried herbs, spices, flowers, fruit, seeds, roots, or leaves of other plants; they do not typically contain caffeine as make traditional teas.

Regarded for thousands of years in the East as a key to good health, happiness, and wisdom, tea has caught the attention of researchers in the West, who are discovering the many health benefits of different types of teas.

Studies have found that some teas may help with cancer, heart disease, and diabetes; encourage weight loss; lower cholesterol, and bring about mental alertness. Tea also appears to have antimicrobial qualities.

“There doesn’t seem to be a downside to tea,” says American Dietetic Association spokeswoman Katherine Tallmadge, MA, RD, LD. “I think it’s a great alternative to coffee drinking. First, tea has less caffeine. It’s pretty well established that the compounds in tea – their flavonoids – are good for the heart and may reduce cancer.”

Although a lot of questions remain about how long tea needs to be steeped for the most benefit and how much you need to drink, nutritionists agree any tea is good tea. Still, they prefer brewed teas over bottled ones to avoid the extra calories and sweeteners.

Health Benefits of Tea: Green, Black, and White Tea

Tea is a name given to a lot of brews, but purists consider only green tea, black tea, and white tea. They are all derived from the Camellia sinensis plant, a shrub native to China and India, and contain unique antioxidants called flavonoids. The most potent of these, known as ECGC, may help against free radicals that can contribute to cancer, heart disease, and clogged arteries.

All these teas also have caffeine and theanine, which affect the brain and seem to heighten mental alertness.

The more processed the tea leaves, usually the less polyphenol content is. Polyphenols include flavonoids. Oolong and black teas are oxidized or fermented, so they have lower concentrations of polyphenols than green tea, but their antioxidizing power is still high.

Here’s what some studies have found about the potential health benefits of tea:

• Green tea: Made with steamed tea leaves, it has a high concentration of EGCG and has been widely studied. Green tea’s antioxidants may interfere with the growth of bladder, breast, lung, stomach, pancreatic, and colorectal cancers; prevent clogging of the arteries; burn fat, counteract oxidative stress on the brain; reduce risk of neurological disorders like Alzheimer’s and Parkinson’s diseases, reduce risk of stroke, and improve cholesterol levels.
• Black tea: Made with fermented tea leaves, black tea has the highest caffeine content and forms the basis for flavored teas like chai, along with some instant teas. Studies have shown that black tea may protect the lungs from damage caused by exposure to cigarette smoke. It also may reduce the risk of stroke.
• White tea: Uncured and unfermented. One study showed that white tea has the most potent anticancer properties compared to more processed teas.
• Oolong tea: In an animal study, those given antioxidants from oolong tea were found to have lower bad cholesterol levels. One variety of oolong, Wuyi, is heavily marketed as a weight loss supplement, but science hasn’t backed the claims.

Health Benefits of Tea: Herbal Teas

Made from herbs, fruits, seeds, or roots steeped in hot water, herbal teas have lower concentrations of antioxidants than green, white, black, and oolong teas. Their chemical compositions vary widely depending on the plant used.

Varieties include ginger, ginkgo Biloba, ginseng, hibiscus, jasmine, rosehip, mint, rooibos (red tea), chamomile, and echinacea.

Limited research has been done on the health benefits of herbal teas, but claims that they help to shed pounds, stave off colds, and bring on restful sleep are largely unsupported.

Here are some findings:

• Chamomile tea: Its antioxidants may help prevent complications from diabetes, like loss of vision and nerve and kidney damage, and stunt the growth of cancer cells.
• Echinacea: Often touted as a way to fight the common cold, the research on echinacea has been inconclusive.
• Hibiscus: A small study found that drinking three cups of hibiscus tea daily lowered blood pressure in people with modestly elevated levels.
• Rooibos (red tea): A South African herb that is fermented. Although it has flavonoids with cancer-fighting properties, medical studies have been limited.

Health Benefits of Tea: Instant teas

Instant tea may contain very few amounts of actual tea and plenty of sugars or artificial sweeteners. For health’s sake, check out the ingredients on the label.

Can Tea Be Bad for Your Health?

Most teas are benign, but the FDA has issued warnings about so-called dieter’s teas that contain senna, aloe, buckthorn, and other plant-derived laxatives.

The agency also warns consumers to be wary of herb-containing supplements that claim to kill pain and fight cancer. None of the claims is backed by science, and some of the herbs have led to bowel problems, liver and kidney damage, and even death.

The FDA cautions against taking supplements that include:

• Comfrey
• Ephedra
• Willow bark
• Germander
• Lobelia
• Chaparral

These cautions aside, nutritionists say to drink up and enjoy the health benefits of tea.

“You want to incorporate healthy beverages in your diet on a more regular basis to benefit from these health-promoting properties,” says Diane L. McKay, Ph.D., a Tufts University scientist who studies antioxidants. “It’s not just about the foods; it’s about what you drink, as well, that can contribute to your health.”

Source Of 

• Caffeine (traditional teas, not herbal)
• Polyphenols
  • Flavonols – myricetin, quercetin, kaempferol
  • Theaflavins – formed when black tea leaves are oxidized
  • Catechins – found in green tea; epigallocatechin-3 gallate (EGCG) is the main form

Most traditional teas do not contain a significant amount of nutrients but are rich in polyphenols. These are plant chemicals that give teas their distinct flavor and aroma and may have health-promoting properties.

Tea and Health

Animal studies suggest potential health benefits of tea due to its high polyphenol content. Human studies have generally been less conclusive yet show promise. Observational research has found that tea consumption of 2-3 cups daily is associated with a reduced risk of premature death, heart disease, stroke, and type 2 diabetes. [2] However, there may be an increased risk of esophageal and stomach cancers from drinking tea that is too hot (more than 131-140° F [55-60° C]). [2,3] Randomized controlled trials are needed to confirm if these healthful and harmful associations are causal. In the meantime, there appears to be little risk associated with drinking tea except for frequent consumption of very hot tea. So pick a color, let it cool, and enjoy a cup!

Spotlight on tea and antioxidants

Polyphenols, or flavonoids, are likely a key component of what makes tea a healthful drink. These chemical compounds act as antioxidants, which control the damaging effects of free radicals in the body. Free radicals can alter DNA by stealing its electrons, and this mutated DNA can increase LDL cholesterol or alter cell membrane traffic—both harmful to our health. Though green tea is often believed to be richer in polyphenols than black or oolong (red) teas, studies show that—with the exception of decaffeinated tea—all plain teas have about the same levels of these chemicals, albeit in different proportions. Green tea is richest in epigallocatechin-3 gallate, whereas black tea is richest in theaflavins; research has shown that both can exert health benefits. Herbal teas contain polyphenols as well but will vary highly depending on their plant origin.

Indeed, one reason for conflicting results in observational studies may be the wide variations in tea types with varying flavonoid content. [4] Where the tea leaves are grown, the specific blend of tea leaves, type of processing, and addition of ingredients such as milk, honey, and lemon can alter specific flavonoid content. How accurately people report their tea intake (e.g., type, amount, brew strength) and their overall diet (e.g., do they eat other foods rich in flavonoids?) are other factors that need to be clarified as they can affect study results. For example:

• Some research suggests that the protein and possibly the fat in milk may reduce the antioxidant capacity of tea. [5] Flavonoids are known to “deactivate” when binding to proteins, so this theory makes scientific sense. [6]
• One study that analyzed the effects of adding skimmed, semi-skimmed, and whole milk to tea concluded that skimmed milk significantly reduced the antioxidant capacity of tea. Higher-fat milk also reduced the antioxidant capacity of tea, but to a lesser degree. [7] All said, in practice, it’s important to keep in mind that tea—even tea with a splash of milk—can be a healthful drink.