But ConsumerLab.com’s testing has found that even if lead is found in the leaves used in green tea bags, it doesn’t appear to be absorbed into the water. Cooperman says his team was concerned about lead content in matcha, because people consume the ground green tea leaves directly rather than in bags. However, their testing showed that among the six popular matcha brands they tested—DoMatcha, Encha Organic Matcha, Rishi Teahouse Matcha, Teavana Imperial Matcha, Kirkland Signature Green Tea and The Republic of Tea Double Green Matcha Tea—the powders were not contaminated by lead or other metals, and also did not contain pesticides. As of now, Cooperman says he doesn’t believe lead exposure is a risk in the matcha currently sold in the United States.
Like black and green tea, rooibos is rich in polyphenols, such as rutin and quercetin. Cell and animal studies, mostly from South Africa, have shown that rooibos extracts have antioxidant, immune-stimulating, and anti-cancer properties. But studies of rooibos tea in people are limited. There’s little or no evidence to back claims that it relieves constipation, headaches, eczema, asthma, insomnia, high blood pressure, mild depression, ulcers, diabetes, and so on.
In a decade-long study of Japanese adults, death from all causes together, and also death from specifically heart disease and stroke, were all reduced in both women and men who drank the most green tea (5 or more cups per day) versus those who drank less than one cup per day. Another study found that those who drank the most green tea were 76% less likely to die during the 6 year study period.
Eucalyptus (Eucalyptus Globulus), Ginger (Zingiber Officinale), Anise (Pimpinella Anisum), Tamarind (Tamarindus Indica), Red Raspberry (Rubus Idaeus), Cranberry, Blackberry, Knapweeds (Centaurea), Cornflower(Cyanus), Chamomile (Chamomilla Recutita), Ginseng (Panax Ginseng), Rose Hips (Rosa Canina Fructus), Lemon Grass (Cymbopogon Citratus), Fennel (Foeniculum Vulgare)
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.
An animal study published in 2009 in “Phytomedicine” found that green rooibos tea helped regulate glucose metabolism, preventing increases in fasting blood glucose levels during the course of the five-week study. This effect is a result of aspalathin, a compound found in green rooibos. Poor glucose tolerance and high fasting glucose levels are signs of type-2 diabetes and are common in obesity. The study suggests rooibos tea may help keep blood glucose levels in check, preventing sharp spikes and falls that can trigger symptoms of hunger and possibly leading to lower calorie consumption.
So-called "detox" teas have been popular for years, primarily among people who frequent health-food stores, or consult with alternative practitioners. These days, though, they've become big business, and a handful of celebrities are touting their weight-loss benefits on social media. In a way, detox teas have become the liquid version of waist trainers–the before and after results are often dramatic, and their celeb backing generates buzz, but you may be wondering: Do they really work, and are they safe? Before you plunk down your hard-earned money and start sipping, here are five things you should know.
Rooibos tea is anti-inflammatory in nature, which means that it reduces blood pressure and scavenges free radicals like other antioxidants. Quercetin, another powerful antioxidant found in rooibos tea, has been linked to preventing a wide variety of heart conditions. It promotes an increase in HDL cholesterol (good cholesterol) and inhibits the LDL cholesterol (bad cholesterol) from binding to the walls of arteries and blood vessels.