What does tea have in common with kale, wine, apples and tomatoes?
All of these contain a type of antioxidant called a flavonol. There are many types of flavonols out there but the ones that tea is particularly rich in are called quercetin and myricetin. What is so spectacular about flavonols?
The journal Neurology published a study that followed the diets of almost 1,000 people in the US with an average age of 81. Researchers found that those with diets richest in flavonols had a 40% less chance of developing Alzheimer's disease compared to those whose diets were lower in flavonols.
While this study does not automatically or directly prove that flavonols directly and solely led to reduced Alzheimer's disease risk, it does add weight to the value of a healthy diet rich in antioxidant-rich food sources, including tea!!!
Well, now that we have another reason to consider tea so great, let's learn about more teas! Last month, we discussed three must-have teas - Black, Green, and Matcha tea. Let's learn about a few more worth keeping in your tea arsenal - White and Oolong tea. Finally, next month, we will highlight several herbal teas to keep handy.
White Tea
Behold a very delicate tea. For this reason, it may even be pricier than other teas you find. But we love it just the same!
Like green and black tea, white (and oolong, our next tea) all come from dried leaves of the same plant - the Camellia sinensis bush. For white tea, the leaves and buds are picked just before they fully open, when the buds are still covered in tiny, white hairs (hence, the name). These leaves are then completely steamed to prevent any discoloration. Then, it is quickly and carefully dried to prevent and further oxidation.
Of all the teas from this plant, this one is the least oxidized. Without any of that oxidation (again, think "browning" of apples or avocados), tea from white tea is usually lighter in color. Since white tea is less processed than green and black tea, it is also high in antioxidants.
FLAVOR PROFILE: delicate, sweet, floral, fruity, subtle
SEVERAL RESEARCHED HEALTH BENEFITS:
- White tea has an enriched content of epigallocatechin-3-gallate (EGCG) and methylxanthines (such as caffeine) compared to green and black tea. These two compounds are known to affect fat cells. One test-tube study found that these compounds in white tea have the ability to interfere with the life cycle of a fat cell. It found that an extract of white tea is effective in both breaking down fat and inhibiting fat cell formation.
- Did you know that tea contains fluoride? In proper amounts, fluoride helps prevent cavities and decay by coming in direct contact with the tooth enamel.
- What makes white tea stand out apart from black and green tea is, as aforementioned, it is minimally processed. Therefore, white tea is typically richer in potent flavonoid antioxidants, including catechins and other polyphenols. Being minimally processed, its catechins are considered to be more active and protective. This is also what makes white tea potentially more protective against cancers. Some of the cancers white tea has been studied against are lung and colon cancer. While more research is still needed, the results are promising for anti-cancer benefits, specifically for preventing growth of cancer cells and protecting cells from DNA damage.
CAFFEINE CONTENT: It is generally known to be lower in caffeine than black or green tea because the original white tea plant native to China is significantly lower in caffeine than other tea plants. However, some white teas may have just as much caffeine as green or black tea. Much of it depends on where the tea was cultivated and how it was processed. It is best to consult the packaging of your white tea.
RECIPE: Try Silver Needle or White Peony white teas. Because of the wonderfullly delicate and subtle flavor, white teas are best enjoyed plain (no milk or sugar needed), brewed with just hot water for 4-5 minutes. (Check packaging of your white tea variety as some leaves are more delicate and only need 2-3 minutes). Thankfully, white tea is a bit more forgiving so it won't taste overly bitter if you accidentally brew it a little longer than recommended.
Oolong Tea
Oolong tea falls somewhere between white tea and green or black tea when it comes to oxidation. It is semi-oxidized.
FLAVOR PROFILE: robust, earthy, sometimes sweet
SEVERAL RESEARCHED HEALTH BENEFITS:
- Heart health: One study concluded that oolong tea consuption is associated with a reduced risk of death from cardiovascular disease. Another Chinese study found that long-term tea consumption is associated with reduced risk of stroke. Interestingly, one study demonstrated that even after just one month of regular oolong tea consumption, the progression of atherosclerosis (hardening of the arteries) was slowed down.
- It can help reduce inflammation
CAFFEINE CONTENT: At about 38 milligrams of caffeine per cup, oolong tea's caffeine content is 1/3 less than that of an 8 ounce serving of coffee, depending on how long the tea leaves are steeped. A longer steep time will render a tea with a higher caffeine content.
RECIPE:
- Plain: best consumed plain, preferably brewed in a clear pot so you can observe how the pellets or balls that the tea leaves are rolled into expand and bloom in when they come into contact with hot water.
- Iced Oolong Tea Lemonade = iced oolong tea + freshly squeezed juice of 1-2 lemons + stevia
References
Dietary flavonols and risk of Alzheimer dementia. Thomas M. Holland, Puja Agarwal, Yamin Wang, Sue E. Leurgans, David A. Bennett, Sarah L. Booth, Martha Clare Morris. Neurology Apr 2020, 94 (16) e1749-e1756; DOI: 10.1212/WNL.0000000000008981.
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