Even organically grown green teas have been shown to contain lead, which is absorbed by the plant from the environment, particularly tea grown in China. When traditional green tea is steeped, about 90% of the lead stays in the leaf, which is discarded. With matcha, since the whole leaf is consumed, you will ingest more lead. One independent group, ConsumerLab.com, which tested teas, estimates that a cup of matcha may contain as much as 30 times more lead than a cup of green tea. Therefore, they recommend drinking no more than one cup daily, and not serving it to children.
Today, an estimated 2.5 million tons of tea leaves are produced each year throughout the world, with 20 percent of that being green tea. Green tea didn’t become popular or widely distributed outside of Asia until about the early 1900s. China, other countries in Asia, countries in North Africa, the United States and Europe currently consume the most green tea worldwide.
Like gyokuro, matcha is shaded before plucking. The plucked and processed leaf is called tencha. This product is then ground into a fine powder, which is matcha. Because the tea powder is very perishable, matcha is usually sold in small quantities. It is typically rather expensive. Matcha is the type of tea used in the Japanese tea ceremony. It is prepared by whisking the tea with hot water in a bowl, until the surface is frothy. If the water is too hot, the tea may become overly bitter.
Jump up ^ Serban C, Sahebkar A, Antal D, Ursoniu S, Banach M (September 2015). "Effects of supplementation with green tea catechins on plasma C-reactive protein concentrations: A systematic review and meta-analysis of randomized controlled trials". Nutrition (Systematic review & meta-analysis). 31 (9): 1061–71. doi:10.1016/j.nut.2015.02.004. PMID 26233863.
This tea is a rich source of antispasmodic agents, which can ease severe stomach cramps and abdominal pains. This is mainly due to the activation of K+ (potassium) ions in the body without antagonizing the activities of calcium, according to a report published in the Basic & Clinical Pharmacology & Toxicology. This can reduce the presence of hyperactivity in the gastrointestinal tract, thus preventing diarrhea and other intestinal issues.
Liver problems have been reported in a small number of people who took concentrated green tea extracts. Although the evidence that the green tea products caused the liver problems is not conclusive, experts suggest that concentrated green tea extracts be taken with food and that people discontinue use and consult a health care provider if they have a liver disorder or develop symptoms of liver trouble, such as abdominal pain, dark urine, or jaundice.
The use of matcha in modern drinks has also spread to North American cafés, such as Starbucks, which introduced "Green Tea Lattes" and other matcha-flavoured drinks after matcha became successful in their Japanese store locations. As in Japan, it has become integrated into lattes, iced drinks, milkshakes, and smoothies. A number of cafes have introduced lattes and iced drinks using matcha powder. It has also been incorporated into alcoholic beverages such as liqueurs and matcha green tea beers.
Several population-based clinical studies have shown that both green and black teas may help protect against cancer. Early clinical studies suggest that the polyphenols in tea, especially green tea, may play an important role in the prevention of cancer. Researchers also believe that polyphenols help kill cancerous cells and stop them from growing.
In fact, there is no hard evidence backing the claims made by tea companies that their detox teas actually purify human cells. However, high-quality teas can help support the body’s natural daily process of detoxification—just as much as other foods and drinks can hurt this system, says Laura Lagano, R.D., a New Jersey-based holistic nutritionist. (Discover more about the health benefits of teas such as chamomile, rosehip, or black tea.)
The available research on matcha includes a small pilot study published in the International Journal of Sports Nutrition and Exercise Metabolism in 2018. For the study, women consumed matcha green tea beverages before a 30-minute brisk walk. Researchers found that matcha consumption enhanced fat oxidation (the breakdown of fat into smaller molecules to be used for energy) during the walk.