The man told the health care workers who treated him that on the day of his heart attack he had downed eight to 10 energy drinks — and that he did that on most days, according to the case report.
It was believed that his immoderate energy drinking caused a blood clot to form that partially blocked a blood vessel near his heart, leading to the heart attack, according to the case report.
"Energy drink consumption is a growing health concern due to limited regulation and increasing use, especially in younger demographics," the researchers wrote in the case report.
"With substantially higher caffeine content than soft drinks or coffee beverages, as well as [containing] other poorly studied substances, there is significant potential for harm, especially when consumed in large quantities."
The man arrived at a hospital nine hours after he began having chest pain. His left arm felt numb, he was sweating profusely and he reported vomiting prior to his arrival at the hospital.
In addition to his daily energy-drink habit, he also said he had smoked a pack of cigarettes a day for the past two years.
Doctors treated the man for his heart attack, and he recovered and eventually went home two days later. He said he would quit smoking and drinking energy drinks.
The excessive levels of caffeine and other potentially harmful substances in energy drinks may have reduced the blood flow in the man's coronary blood vessel to such an extent that a blood clot was able to form, causing the heart attack, according to the case report.
However, it is also possible that the man's smoking led to the constriction of the coronary artery, the authors speculated. The man had no other apparent risk factors for heart attack beyond consuming a lot of energy drinks and smoking, the authors wrote.
Although, it is not yet proven that there is a cause-and-effect relationship between energy drink overuse and heart attack risk. Further studies are needed to confirm the link. The FDA is currently investigating some reports of adverse events associated with energy drinks, according to the agency.
Source: Live Science