Breakfast key to cancer risk Hot Tea Can Increase The Risk Of Throat Cancer
By Live Dr - Sat Mar 28, 1:28 pm
Drinking Very Hot Tea Can Increase The Risk Of
ScienceDaily (Mar. 28, 2009) — People are advised to wait a few minutes before drinking a cup of freshly-boiled tea today as a new study, published on the British Medical Journal website, finds that drinking very hot tea (70°C or more) can increase the risk of cancer of the oesophagus, the muscular tube that carries food from the throat to the stomach.
The study was carried out in northern Iran, where large amounts of hot tea are drunk every day.
But an accompanying editorial says these findings are not cause fo
r alarm and the general advice is to allow foods and beverages to cool a little before swallowing.
Cancers of the oesophagus kill more than 500,000 people worldwide each year and oesophageal squamous cell carcinoma (OSCC) is the commonest type. In Europe and America, it is mainly caused by tobacco and alcohol use and is more common in men than in women, but drinking hot beverages is also thought to be a risk factor.
Golestan Province in northern Iran has one of the highest rates of OSCC in the world, but rates of smoking and alcohol consumption are low and women are as likely to have a diagnosis as men. Tea drinking, however, is widespread, so researchers set out to investigate a possible link between tea drinking habits and risk of OSCC.
They studied tea drinking habits among 300 people diagnosed with OSCC and a matched group of 571 healthy controls from the same area. Nearly all participants drank black tea regularly, with an average volume consumed of over one litre a day.
Compared with drinking warm or lukewarm tea (65°C or less), drinking hot tea (65-69°C) was associated with twice the risk of oesophageal cancer, and drinking very hot tea (70°C or more) was associated with eight-fold increased risk.
Likewise, compared with drinking tea four or more minutes after being poured, drinking tea less than two minutes after pouring was associated with a five-fold higher risk.
There was no association between the amount of tea consumed and risk of cancer.
To minimise errors between reported and actual tea temperatures, the researchers then measured the actual temperature that tea was consumed by nearly 50,000 residents of the same area. This ranged from less than 60°C to more than 70°C and there was a moderate agreement between reported tea drinking temperature and actual temperature measurements.
Our results show a strong increase in the risk of oesophageal squamous cell carcinoma associated with drinking hot or very hot tea, say the authors.
Previous studies from the United Kingdom have reported an average temperature preference of 56-60°C among healthy populations.
They suggest that informing the population about the hazards of drinking hot tea may be helpful in reducing the incidence of oesophageal cancer in Golestan and in other high risk populations where similar habits are prevalent.
These results provide persuasive evidence that drinking tea at temperatures greater than 70°C markedly increases the risk of oesophageal squamous cell carcinoma, says David Whiteman from the Queensland Institute of Medical Research in Australia in an accompanying editorial.
This report also lends support to the notion that thermal injury may be a cause of epithelial cancers, though he points out that the way in which heat promotes tumour development is not clear and warrants further investigation.
However, he stresses that these findings are not cause for alarm, and they should not reduce public enthusiasm for the time honoured ritual of drinking tea. Instead he suggests waiting at least four minutes before drinking a cup of freshly boiled tea, or more generally allowing foods and beverages to cool from “scalding” to “tolerable” before swallowing.
An accompanying video features interviews with some of the researchers as well as original footage from Iran in the early days of the study.
Starting the day with a traditional cooked breakfast and a steaming cup of tea may increase a woman’s risk of throat cancer, research suggests. The best way to minimise risk is to begin the day with a light breakfast such as cereal or fruit.
These factors go a long way to explaining why women in the UK die of oesophageal cancer much more frequently than their European neighbours
Professor Nick Day
Scientists found that women who eat a fry up each morning are at twice the risk of the most common form of throat, or oesophageal, cancer.
Cancer of the oesophagus – the tube connecting the stomach with the upper throat – affects approximately 7,000 people in the UK every year. Radical surgery is often needed to try to halt its spread.
Drinking lots of tea – particularly when piping hot – also seems to increase risk, perhaps because of the burning effect of the liquid as it passes down the food pipe.
But the researchers warned that skipping breakfast altogether is no way to avoid the disease.
A food-free morning carries an even greater risk than a plateful of sausages, bacon and egg.
Focus on women
Lead researcher Dr Linda Sharp, of Aberdeen University, said: “Studies into oesophageal cancer have often concentrated on men, where the major risk factors are smoking and drinking.
“But women have, at least in the past, tended to smoke and drink less heavily than men, and we wanted to know if other lifestyle factors influenced women’s risk.”
Scaldingly hot drinks may burn the inside of the food pipe, causing damage which in time could increase the risk of cancer
Dr Linda Sharp
Concentrating on the most common form of oesophageal cancer, called squamous cell carcinoma, the researchers questioned 156 women with the disease from Oxfordshire, East Anglia, Trent and Eastern Scotland about their lifestyles.
Women who ate a cooked breakfast each morning were at more than twice the risk of developing oesophageal cancer as those who began the day with a light breakfast – classified as anything other than a fry up.
But women who skipped breakfast altogether had a risk that was a startling five times higher than the light breakfast group.
Professor Nick Day, of the Cancer Research Campaign, said: “As in other parts of the world where women have relatively high rates of oesophageal cancer, there’s a strong link with poor diet and drinking lots of very hot tea.
“By poor diet, I mean not only the low intake of salads, fruit and fruit juice, but also the pattern of eating, notably the tendency to skip breakfast.
“Taken together, these factors go a long way to explaining why women in the UK die of oesophageal cancer much more frequently than their European neighbours.”
Around 30% of cancers may be preventable by dietary improvement
Dr Tim Key
The study suggested that women who drink lots of tea are at over three times the risk of the disease of non tea-drinkers, although because of the large amount of variation between women, the evidence was not conclusive.
But women who consumed their hot drinks immediately after making them were three times more likely to develop the disease as those who waited a while for their drinks to cool down.
Dr Sharp said: “It’s interesting that the risk seems to be higher with tea than with coffee, but perhaps people drink their tea at a higher temperature.”
The study also confirmed that smoking can increase women’s risk of oesophageal cancer.
Dr Tim Key, a diet expert at Imperial Cancer Research Fund, said: “Research into diet and cancer is very important as around 30% of cancers may be preventable by dietary improvement.”