High tea, moderate coffee consumption linked to reduced CHD mortality
MedWire News: Moderate-to-high consumption of tea and moderate consumption of coffee are associated with reduced risk for coronary heart disease (CHD) mortality, a Dutch study suggests.
In the journal Arteriosclerosis, Thrombosis, and Vascular Biology, Joline Beulens (University Medical Centre Utrecht, The Netherlands) and colleagues explain: “While previous studies have shown that coffee and tea seem to reduce the risk of heart disease, evidence on stroke risk and mortality risk from heart disease was not conclusive.
“Our results found the benefits of drinking coffee and tea occur without increasing risk for stroke or death from all causes.”
They add: “The cardiovascular benefits of these beverages may be explained by the presence of antioxidants such as chlorogenic acid found in coffee and flavonoids found in tea.”
The team conducted the European Prospective Investigation into Cancer and Nutrition (EPIC-NL) study, assessing the tea and coffee consumption of 37,514 healthy Dutch men and women aged 20 to 69 years. At baseline, all the participants completed food frequency questionnaires requesting an indication of the number of cups of tea or coffee consumed daily during the past year. A clinical assessment of risk factors such as hypertension and obesity was also performed at baseline.
During the 13-year follow-up period, there were 1881 incident cases of cardiovascular morbidity: 563 from stroke and 1387 from CHD.
Coffee consumption showed a U-shaped association with CHD, with the risk reduced by 21% (p=0.01) in people who drank two to three cups of coffee per day, compared with those who drank less than two cups or four or more cups per day. Coffee consumption also reduced the risk for CHD mortality by 36% in people who drank three to six cups per day compared to those who drank less than three cups; however, this reduction was not significant (p=0.12).
Tea had an inverse linear association with CHD, with people drinking more than six cups per day seeing the greatest reduction in CHD risk, at 36% (p=0.02), compared with those who drank less than one cup of tea per day. A U-shaped association was found between tea consumption and CHD mortality risk, with a risk reduction of 45% occurring among people who consumed three to six cups of tea daily (p=0.03).
However, tea and coffee consumption were not associated with stroke risk or all cause mortality.
The results remained true after adjusting for confounding variables such as smoking status and alcohol intake, and were not explained by interactions between coffee and tea consumption and hypertension, diabetes, hypercholesterolemia, or smoking.
Beulens et al name the main limitations of the study as the use of patient reported data on tea and coffee consumption, and the use of baseline coffee and tea consumption values only. However, the team explains that adjustments were made to minimize the level of bias these limitations contributed to the findings.
They conclude: “We strengthen the evidence on the lower risk of CHD associated with coffee and tea consumption; however, neither coffee nor tea was associated with the risk of stroke or all-cause mortality.”
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By Lauretta Ihonor