Is green tea actually good for you? The health benefits and hype revealed
It's a drink which has become synonymous with a healthy lifestyle - but is green tea the magical potion many health sites would have us believe?
Green tea has been popular in China for centuries, and has been used in traditional Chinese medicine to treat a number of health issues - including depression .
Its virtues have also been extolled by celebrities and so-called health experts for a number of reasons.
These include its purported ability to help weight-loss , as well as containing antioxidants which are believed to help combat different types of cancer, heart disease and Alzheimer's.
Given these claims, it's easy to see green tea as sort of magical elixir.
But what is fact, and what is hype? Luckily, the NHS have separated the two...
Is green tea actually good for you? Real benefits revealed.
1. Green tea and weight loss
Green tea contains B vitamins, folate (naturally occurring folic acid), manganese, potassium, magnesium, caffeine and other antioxidants, such as catechins.
It's catechins - along with green tea's naturally occurring caffeine - which are thought to help the body burn more calories.
Weight-loss products containing green tea have a higher concentration of catechins and caffeine than the typical green tea beverage.
However, there's some bad news.
A well-conducted review from 2012 of 18 studies involving 1,945 people found no significant effect of weight loss from drinking green tea.
2. Green tea and cholesterol
Thanks again to the catechins, in a reputable review from 2013 of 11 studies involving 821 people, it was found daily consumption of green and black tea (as a drink or a capsule) could help lower cholesterol and blood pressure.
It's important to note, however, that the authors of the study pointed out the trials were short-term, and cautioned longer-term trials would be needed to substantiate their findings.
These were back up by an earlier review in 2011, which found drinking green tea enriched with catechins led to a small reduction in cholesterol, a main cause of heart disease and stroke.
Though no one could say for certain how much green tea a person would need to drink to reap the benefits.
3. Green tea and cancer
On this the NHS is clear.
There is no evidence drinking green tea protects against different types of cancer.
Back in 2009 a review (involving 51 studies, with more than 1.6 million participants) was carried out which looked into a link between drinking green tea and cancers of the bowel, prostate, breast, mouth and lungs.
The authors of the review concluded any evidence of an association link between green tea and cancer was weak and "highly contradictory".
Since then, a study in 2015 examined the combination of the drug Herceptin and a cancer-fighting compound found in green tea to see how they treated stomach and breast cancer.
Initial results in the laboratory were promising and human trials are now being planned - but this is not to say drinking green tea while taking Herceptin will improve the efficacy of your treatment.
4. Green tea and Alzheimer's
It's believed there is a link between green tea consumption and delaying or preventing Alzheimer's.
However, the evidence is weak and was based on tests done in 2010 on animal cells.
While these tests found a green tea preparation rich in antioxidants protected against the nerve cell death associated with dementia and Alzheimer's, it remains to be seen whether the same test in human trials could reproduce the same results.
5. Tooth decay
Some good news - green tea may be a good weapon against tooth decay.
A small study from 2014 compared how a green tea mouthwash fared against the more popular antibacterial mouthwash chlorhexidine.
While the results suggested they were equally effective, green tea mouthwash has the added benefit of being cheaper.
6. Blood pressure
Several studies have looked into the evidence of whether blood pressure can lowered by drinking green tea.
While this evidence did show a link between blood pressure reduction in people who with high blood pressure and drinking green tea, the reduction was described as "modest".
It is still unclear whether such a reduction could have a greater impact, i.e. preventing strokes or heart disease.
The final verdict on green tea, according to a dietitian.
Dietitian and BDA spokesperson Alison Hornby, admits the evidence about green tea's health benefits is inconclusive.
She says: "In the Far East, green tea has been used as a treatment for a variety of conditions ranging from arthritis to weight loss, as well as a preventative measure for diseases such as cancer, although the evidence for the majority of these conditions is weak or lacking.
"However, as a social drink, it appears to be safe in moderate amounts, so lovers of green tea can continue to enjoy it."