Red Bull can worsen heart risk - The Telegraph 7th November 2007

People with high blood pressure or heart disease should avoid energy drinks such as Red Bull as they could make their conditions worse, scientists have warned. Researchers claimed energy drinks - a £1.5billion worldwide market - cause changes in the body which could put those with existing heart and circulation problems at risk. Healthy volunteers given two energy drinks per day for a week experienced significant increases in both heart rate and blood pressure, the study found.

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