Studies follow one another on the benefits or harms of coffee. On the bright side, the consumption of this hot drink would reduce the risk of death in survivors of myocardial infarction, as well as that of developing diabetes and certain cancers. On the negative side, coffee, in large quantities, increases blood pressure and promotes anxiety, palpitations and sleep disturbances. Considering its harms to those at risk, Hiroyasu Iso’s team at the National Center for Global Health and Medicine in Tokyo, Japan, wanted to assess whether the benefits applied to people who already had high blood pressure.
The researchers therefore recorded the consumption of hot drinks and the state of health of nearly 19,000 Japanese from the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. During the 19 years of follow-up, 842 deaths related to cardiovascular events were documented. After analyzing the data, the scientists found that drinking two or more cups of coffee (200ml each) a day was associated with a doubled risk of dying from cardiovascular disease in people with hypertension. On the other hand, this risk was not increased in those who were satisfied with a single cup daily. Same observation for tea: this drink was not linked to any increase in cardiovascular risk in hypertensives.
How to explain it?
“People with high blood pressure are more sensitive to the effects of caffeine,” the researchers explain. “And the harms of this molecule outweigh any protective effects. »
As for tea, the presence of polyphenols could explain why this drink does not expose to the same risks as coffee. Indeed, the presence of these antioxidant and anti-inflammatory micronutrients delays its assimilation in the body. Not to mention that the same amount of coffee contains 3 to 4 times more caffeine than tea.