A young man's heart problems may have been triggered by his excessive consumption of energy drinks — he ended up in the hospital with heart failure after consuming four energy drinks per day for two years, according to a new report of the case.
The findings add to a growing body of evidence linking energy drink consumption with heart problems, leading the authors to call for warnings about the dangers of drinking these beverages in large amounts.
The 21-year-old man went to the hospital after he experienced progressively worse shortness of breath for four months as well as weight loss, according to the report, published Thursday (April 15) in the journal BMJ Case Reports.
Related: 10 interesting facts about caffeine
He reported drinking four 500-milliliter cans of energy drinks every day for about two years, with each can containing 160 milligrams of caffeine. (A typical cup of coffee contains about 90 mg of caffeine.)
The man recalled that he occasionally had episodes of indigestion, tremors and a racing heartbeat, which he didn't seek care for in the past. He felt so unwell and lethargic in recent months that he had to stop his university studies, according to the report, from doctors at St Thomas' Hospital in London.
After a barrage of tests, the man was diagnosed with two potentially life-threatening conditions: heart failure and kidney failure. Heart failure occurs when the heart muscle can't pump enough blood to meet the body's needs; and kidney failure happens when the kidneys can't properly filter waste products from the blood. In the man's case, the two conditions appeared to be unrelated, but they each had serious effects. The man's doctors discussed whether he needed a double (heart and kidney) organ transplant.
His kidney failure was due to a long-standing but previously undiagnosed condition called chronic obstructive uropathy, when urine can't properly drain through the urinary tract tubes and so it backs up into the kidneys.
His doctors considered a number of possible causes for his heart failure, including "broken heart syndrome," when the heart's main pumping chamber becomes enlarged and weakened, and myocarditis, or inflammation of the heart. However, neither condition fit with the man's history and test results. The most likely explanation for his heart failure was his high level of energy drink consumption, the authors concluded, although they can't prove this for certain.
Previous studies have linked energy drink consumption with concerning cardiovascular effects, including increased blood pressure and abnormal heart rhythms. There have been several reports of young people who have suffered heart attacks and heart rhythm problems after consuming energy drinks, Live Science previously reported.
After 58 days in the hospital, the man was cleared to go home and was prescribed several heart medications. He stopped drinking energy drinks completely and his heart function improved so much that his doctors say he doesn't need a heart transplant at this time. However, he will likely need a kidney transplant at some point in the future.
Some people may be predisposed to heart problems from energy drinks due to underlying biological factors, although more research is needed to determine what these factors are, the authors said.
"This case further highlights the potential cardiovascular dangers of energy drinks in susceptible individuals," the authors wrote. "Clear warnings should be provided about the potential cardiovascular dangers of energy drink consumption in large amounts," they concluded.
Originally published on Live Science.
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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.