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The caffeine found in 5-Hour Energy drinks may give you a needed boost -- but one man says his doctor believes it may also have lead to a fatal medical episode.
"Forty-one years old, I would never have thought that I would have a heart attack at this age," lifelong athlete Richard Perez told NBC 6.
Last month, the physically fit man suffered a massive heart attack from a blocked artery, an ailment his cardiologist reportedly attributed to the energy shot. Perez told doctors he had two 5-Hour Energy drinks every day for the past five years.
Perez is not the first person to blame the supplement for adverse affect.
In fact, the Food and Drug Administration has begun an investigation to determine the cause of 13 deaths that may be at least partially attributable to the drink.
The company which makes 'Energy' was adamant in emphasizing that there is no direct evidence between the reported illnesses and the product.
"It is important to note that submitting a serious adverse event report to the FDA, according to the agency itself, is not construed by the FDA as an admission that the dietary supplement was involved, caused or contributed to the adverse event being reported." the company e-mailed HuffPost in a statement.
At least 30 serious incidents, including heart attacks, convulsions, and spontaneous abortion, were mentioned in the FDA report.
CORRECTION: An earlier version of this story indicated that 5-Hour Energy drinks contain sugar. There is no sugar listed in the ingredients.