Can green tea aid weight loss?
It’s thought the antioxidants catechin and caffeine found in green tea may have a role in helping the body burn more calories – sometimes referred to as speeding up the metabolism – which can help weight loss.
Green tea preparations used for losing weight are extracts of green tea that contain a higher concentration of catechins and caffeine than the typical green tea beverage prepared from a tea bag and boiling water.
A well-conducted review from 2012 of 18 studies involving 1,945 people found no significant effect of weight loss from drinking green tea.
Does green tea cut cholesterol?
A good-quality review from 2013 of 11 studies involving 821 people found daily consumption of green and black tea (as a drink or a capsule) could help lower cholesterol and blood pressure thanks to tea and its catechins. The authors of the review caution that most of the trials were short term and more good quality long-term trials are needed to back up their findings.
Another good-quality review from 2011 found drinking green tea enriched with catechins led to a small reduction in cholesterol, a main cause of heart disease and stroke. However, it’s still not clear from the evidence how much green tea we’d need to drink to see a positive effect on our health, or what the long-term effects of drinking green tea are on our overall health.
Can green tea help prevent or delay Alzheimer’s disease?
Evidence of a positive link between drinking green tea and Alzheimer’s disease is weak. A 2010 laboratory study using animal cells found a green tea preparation rich in antioxidants protected against the nerve cell death associated with dementia and Alzheimer’s disease.
Whether these lab results can be reproduced in human trials remains to be seen. As such, the findings do not conclusively show green tea combats Alzheimer’s disease.
Can green tea lower blood pressure?
A 2014 survey of data from previously published studies looked at the evidence of whether drinking green tea could help lower blood pressure. There was evidence of a modest reduction in people with high blood pressure who consumed green tea. But whether this reduction would lead to clinically significant results, such as preventing the onset of heart disease or stroke, is unclear.