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Tea and coffee 'protect against heart disease'
cup of tea It is still not clear what difference milk makes to the health benefits
Drinking several cups of tea or coffee a day appears to protect against heart disease, a 13-year-long study from the Netherlands has found.
It adds to a growing body of evidence suggesting health benefits from the most popular hot drinks.
Those who drank more than six cups of tea a day cut their risk of heart disease by a third, the study of 40,000 people found.
Consuming between two to four coffees a day was also linked to a reduced risk.
While the protective effect ceased with more than four cups of coffee a day, even those who drank this much were no more likely to die of any cause, including stroke and cancer, than those who abstained.
The Dutch tend to drink coffee with a small amount of milk and black tea without. There have been conflicting reports as to whether milk substantially affects the polyphenols - believed to be the most beneficial substance in tea.
Continue reading the main story
Having a cigarette with your coffee could completely cancel any benefits
Ellen Mason British Heart Foundation
Coffee has properties which could in theory simultaneously increase and reduce risk - potentially raising cholesterol while battling the inflammatory damage associated with heart disease.
But the study in the Journal of the American Heart Association finds those who drank between two and four cups a day lowered the risk of the disease by 20%.
"It's basically a good news story for those who like tea and coffee. These drinks appear to offer benefits for the heart without raising the risk of dying from anything else," said Professor Yvonne van der Schouw, the lead researcher.
Ellen Mason, Senior Cardiac Nurse at the British Heart Foundation, said: "This study adds further weight to the evidence that drinking tea and coffee in moderation is not harmful for most people, and may even lower your risk of developing, or dying, from heart disease.
"However, it's worth remembering that leading a healthy overall lifestyle is the thing that really matters when it comes to keeping your heart in top condition.
"Having a cigarette with your coffee could completely cancel any benefits, while drinking lots of tea in front of the TV for hours on end without exercising is unlikely to offer your heart much protection at all."
Moderate Coffee, Tea Drinking Lowers Heart Disease Risk
And moderate to high tea consumption cuts risk of dying from the condition, study finds
By Ed EdelsonHealthDay Reporter
And moderate to high tea consumption cuts risk of dying from the condition, study finds.
FRIDAY, June 18 (HealthDay News) -- Drinking coffee or tea in moderation reduces the risk of developing heart disease, and both high and moderate tea drinking reduces the risk of dying from the condition, according to a large-scale study from Dutch researchers.
The study, led by physicians and researchers at the University Medical Center Utrecht, examined data on coffee and tea consumption from 37,514 residents of The Netherlands who were followed for 13 years.
It found that people who had two to four cups a day of coffee had a 20 percent lower risk of heart disease compared to those drinking less than two or more than four cups a day. Moderate coffee intake also slightly -- but not significantly -- reduced the risk of death from heart disease and all causes.
Tea's performance was stronger on both counts. Drinking three to six cups of tea a day was associated with a 45 percent reduced risk of death from heart disease, compared to drinking less than one cup a day, and drinking more than six cups of tea a day was associated with a 36 percent lower risk of getting heart disease in the first place.
The apparent protective effects may be linked to antioxidants and other plant chemicals in the beverages, but how they work is unclear, according to researchers.
No effect of coffee or tea consumption on the risk of stroke was seen in the study.
Study authors found, however, that coffee and tea drinkers in The Netherlands had very different health behaviors, with more coffee drinkers smoking and having less healthy diets.
Dr. Suzanne Steinbaum, director of women and heart disease at Lenox Hill Hospital in New York City and a spokeswoman for the American Heart Association, noted that there has been ongoing controversy about the impact of daily tea and coffee consumption on health. "Here is another study that reaffirms there is no increased risk of heart disease and stroke, and in fact, when drinking coffee in moderation, there is possibly a reduction in your risk of heart disease," she wrote on behalf of the AHA.
Experts note, however, that it's too early to make specific recommendations on coffee and tea drinking for the sake of better health, despite a growing number of studies that suggest the beverages may help protect against heart disease.
"Based on current evidence, it is very difficult to come up with an optimum amount of coffee or tea for the general population," said Dr. Frank Hu, professor of nutrition and epidemiology at the Harvard School of Public Health.
Discussing the study from The Netherlands in context of other research, Hu noted that this is not the first report on coffee and tea consumption and heart disease mortality. "Overall, the studies were consistent in showing that higher consumption of coffee did not increase the risk of morbidity or mortality from cardiovascular disease," he said. "Several suggested there might be a slight protective effect."
Those studies also suggested a protective effect of tea, Hu said, but "the problem with this is that different types of tea are consumed in different populations, so it is difficult to compare results in different studies." (Most people in the Dutch study reported using black tea).
Many people still have a lingering belief that coffee might be dangerous, because early studies suggested an increased risk of heart disease, Hu said. Some of those studies used self-reports from people after a heart attack, so there was a problem of "recall bias," Hu noted. "Certainly, moderate consumption is not likely to cause harm in terms of cardiovascular health," he concluded.
"Common sense should always prevail," said Dr. Arthur L. Klatsky, a senior consultant in cardiology at Kaiser Permanente Northern California and an adjunct investigator in its division of research, who led a previous study showing reduced incidence of heart rhythm abnormalities in coffee drinkers. "If you have unpleasant symptoms from caffeine, you should avoid it. Some people get insomnia even if they take it at noon."
But there is evidence that moderate coffee consumption is associated with a decreased risk of type 2 diabetes, Klatsky said.
One possible confounding factor is that people who drink moderate amounts of either coffee or tea tend to have a healthier lifestyle, exercising more and avoiding obesity, said Steinbaum.
Still, "this and other studies have shown that drinking two to four cups of coffee a day is associated with a 20 percent reduction in heart disease," Steinbaum said. When people ask her whether coffee drinking is dangerous, "my response is that drinking coffee is not unhealthy," she said.
The study was published online June 18 in Arteriosclerosis, Thrombosis and Vascular Biology.
on June 18, 2010
Arteriosclerosis, Thrombosis, and Vascular Biology. 2010
Published online before print June 18, 2010, doi: 10.1161/ATVBAHA.109.201939
Submitted on December 19, 2009
Accepted on April 26, 2010
Tea and Coffee Consumption and Cardiovascular Morbidity and Mortality
J. Margot de Koning Gans ; Cuno S.P.M. Uiterwaal ; Yvonne T. van der Schouw ; Jolanda M.A. Boer ; Diederick E. Grobbee ; W. M. Monique Verschuren ; and Joline W.J. Beulens *
From the Julius Center for Health Sciences and Primary Care (J.M.d.K.G., C.S.P.M.U., Y.T.v.d.S., D.E.G., and J.W.J.B.), University Medical Center Utrecht, Utrecht, the Netherlands; and the National Institute for Public Health and the Environment (J.M.A.B. and W.M.M.V.), Bilthoven, the Netherlands.
* To whom correspondence should be addressed. E-mail: J.Beulens@umcutrecht.nl.
Objective―To examine the associations of coffee and tea consumption with risk of morbidity and mortality of stroke and coronary heart disease (CHD) and with all-cause mortality.
Methods and Results―Coffee and tea consumption were assessed with a validated food-frequency questionnaire, and 37 514 participants were observed for 13 years for the occurrence of cardiovascular morbidity and mortality. A U-shaped association between coffee and CHD was found, with the lowest hazard ratio (HR [95% CI]) for 2.1 to 3.0 cups per day (0.79 [0.65 to 0.96]; Ptrend=0.01). Tea was inversely associated with CHD, with the lowest HR (95% CI) for more than 6.0 cups per day (0.64 [0.46 to 0.90]; Ptrend=0.02). No associations between tea or coffee and stroke were found (Ptrend=0.63 and Ptrend=0.32, respectively). Although not significant, coffee slightly reduced the risk for CHD mortality (HR, 0.64; 95% CI, 0.37 to 1.11; Ptrend=0.12) for 3.1 to 6.0 cups per day. A U-shaped association between tea and CHD mortality was observed, with an HR of 0.55 (95% CI, 0.31 to 0.97; Ptrend=0.03) for 3.1 to 6.0 cups per day. Neither coffee nor tea was associated with stroke (Ptrend=0.22 and Ptrend=0.74, respectively) and all-cause mortality (Ptrend=0.33 and Ptrend=0.43, respectively).
Conclusion―High tea consumption is associated with a reduced risk of CHD mortality. Our results suggest a slight risk reduction for CHD mortality with moderate coffee consumption and strengthen the evidence on the lower risk of CHD with coffee and tea consumption.
Key words: coronary heart disease . stroke . mortality . coffee . tea
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