Green tea could lower the risk of colon cancer, say researchers at Seoul National University Hospital in South Korea.
They are testing this in a study involving 180 people who have had polyps – benign growths – removed from their colon; these polyps can be a precursor to colon cancer.
The patients will be given a daily green tea extract pill (nine cups of green tea) or no treatment. The researchers believe compounds in green tea prevent the rogue cells that could lead to polyps from developing.
A previous study by Gifu University in Japan showed just 15 per cent of patients who had the equivalent of ten cups of green tea a day had a recurrence of polyps, compared with 31 per cent recurrence in the untreated group.
Green tea is a drink made from the dried leaves of the Asian plant Camellia sinensis. This tea is drunk widely across Asia. The rates of many cancers are much lower in Asia than other parts of the world. Some people believe this is because of the high intake of green tea.
You may also hear green tea called Chinese tea. The substance in green tea that researchers think is most helpful is called epigallocatechin-3-gallate (EGCG). EGCG is available as green tea extract which some people take as a supplement in liquid or capsules.
People also use green tea to try and reduce their risk of getting cancer. There is some evidence from early studies of green tea to suggest that it may reduce the risk of some cancers. But at the moment the evidence is not strong enough to know this for sure.
More recently black tea has also been promoted as an anti cancer agent. Black tea comes from the same plant as green tea. But black tea is made from the fermented leaves of the plant.
A daily low dose of aspirin should be given to people in their 50s to prevent a heart attack or stroke, new guidelines recommend.
This could provide protection against colon cancer too, a US government ‘task force’ group said.
The US Preventive Services Task Force, an independent panel of experts who review the evidence for preventative medicines, issued draft guidelines this week.
They recommended a daily dose of aspirin if people meet a strict list of criteria — including a high risk of heart disease and a low risk experiencing a side effect like bleeding.
The guidelines said the recommendation is strongest for people in their 50s, but that doctors should decide aspirin therapy on a case-by-case basis for people in their 60s, who can expect a smaller benefit.
The treatment should be offered to people who have at least a 10 per cent risk of a heart attack or stroke over the next decade; have a life expectancy of at least 10 years; and be willing to take daily aspirin that long, the guidelines said.
They should not have other health conditions that could cause bleeding, they said.
This is because a well-known side-effect of prolonged aspirin use is that it can cause haemorrhaging in the brain and gastrointestinal tract.
Aspirin works by making the blood less ‘sticky’, meaning clots do not form, reducing the risk of having a stroke or heart attack.
Aspirin therapy has long been recommended for heart attack survivors.
But whether it should be recommended for ‘primary prevention’— protection against a first heart attack or stroke — is less clear.
And while studies suggest years of daily aspirin use may lower the risk of colon cancer, no major health organisations recommend taking it solely for that reason.
Neither do the new guidelines — the aspirin decision is supposed to be made on the basis of patients’ heart health — but it concluded the cancer information would be useful as doctors and patients discuss the choice.
Professor Douglas Owens, of Stanford University, who sat on the task force that developed the guidelines, said: ‘If you’re a person trying to decide whether to take aspirin, you’d want to be aware of all the potential benefits and the potential harms.’
There is not enough evidence to assess aspirin therapy for those under 50 or over 69, the task force concluded.
The guidelines give a narrower age range than the last time the task force considered the questions, but for the first time includes the information about the possible benefit against cancer for the first time.
The guidelines are in line with American Heart Association recommendations, said Professor Elliott Antman, of Harvard University and former AHA president, who welcomed them.
In contrast, the Food and Drug Administration last year ruled that there wasn’t enough evidence to support marketing aspirin for prevention of first heart attacks.
Cardiovascular disease, including heart attacks and strokes, are the number one cause of death globally, according to the World Health Organisation.
In the UK, the National Institute for Health and Care Excellence (Nice), recommends that people who have had heart disease, a heart attack, or a stroke – or who are a a high risk of having a stroke – should be prescribed a daily aspirin.
An estimated 17.5 million people died from cardiovascular disease in 2012, representing 31 per cent of all global deaths.
Of these deaths, an estimated 7.4 million were due to coronary heart disease (the number one cause of a heart attack) and 6.7 million were due to stroke.