For some, green tea can be an acquired taste. But judging by some of its health benefits, the pungent tea is well worth the scrunched up face.
Here, we explore what it actually is, how it boosts health and whether it’s really a great weight loss aid.
What Is It?
Green tea contains B vitamins, folate, manganese, potassium, magnesium, caffeine and other antioxidants, notably catechins, according to the NHS.
It is made by steaming fresh leaves from the Camellia sinensis plant.
It can be purchased in tea bag form or the tea leaves can be added to a pot of hot water and strained.
“There do seem to be many benefits of consuming green tea,” says nutritionist Charlotte Stirling-Reed. “And there are plenty of research papers that suggest a benefit of, or link the consumption of, green tea to positive health aspects.
“For example, research has suggested that green tea may have benefits in protection against degenerative and chronic diseases, and promising effects on lowering blood pressure.”
It is also believed that green tea has protective effects against cancer. However the NHS states that there is “no evidence” of this.
British Dietetic Association (BDA) spokesperson Chloe Miles tells The Huffington Post UK: “I’d say most of the evidence for green tea is inconclusive.”
She said it may help to lower cholesterol and blood pressure, but adds that more long-term trials are needed.
Stirling-Reed notes that most of the beneficial health effects of green tea are believed to come from its high content of compounds called polyphenols or flavonols.
“These flavonols make up around 30% of the dry weight of the fresh green tea leaf and so green tea itself can play a big part in providing the body with these beneficial compounds,” she says.
According to Neal’s Yard, polyphenols found in green tea can prevent the break down of collagen and cartilage, making it a promising home remedy for issues like arthritis.
Green tea has also been touted as a natural weight loss method, as it is believed that the antioxidants catechin and caffeine may speed up metabolism. But don’t get too excited, as a review of 18 studies involving 1,945 people found no significant effect of weight loss from drinking green tea.
“It might increase energy expenditure and fat oxidation however you’d have to consume a lot to get that effect and the amount of weight loss would be small,” explains the BDA’s Chloe Miles.
“Ultimately green tea is a great food to include in your diet and it may have some beneficial properties that help you look after your health,” adds Stirling-Reed.
“Different people are likely to have different responses to green tea and we don’t know much about this at the moment but, if you enjoy it, there is no problem with consuming it in moderation.”
She concludes: “The health evidence is still limited in humans, and we need much more research to determine the scale of the benefits of drinking green tea, as well as what doses may have any beneficial effects.
“On top of this, we don’t know if very high doses of green tea could actually have negative effects. Therefore it’s not a good idea to consume green tea in large quantities.
“Green tea contains caffeine and therefore, especially for pregnant women, it’s important not to consume too much.”
She adds that the compounds in green tea can affect absorption of iron in the body, which should be taken into account for people at risk of iron deficiency.
“Drinking green tea outside of mealtimes is a way to help combat this,” she advises.