More warnings about over-consuming energy drinks after seemingly fit and healthy 21-year-old man almost died from his addiction

There are more warnings about the over-consumption of energy drinks after an otherwise healthy 21-year-old man almost died from heart failure.

A report by doctors found it was likely an addiction to energy drinks, that have high levels of both sugar and caffeine that caused the problem.

The man drank four 500ml energy drinks a day for two years before he needed hospital treatment for heart failure, according to a new BMJ Case Report.

The university student required intensive care treatment and was so ill that medics were considering whether he needed an organ transplant.

He sought care after suffering for four months with shortness of breath and weight loss.

Blood tests, scans, and ECG readings revealed that he had both heart and kidney failure - with the kidney failure linked to a long standing and previously undiagnosed condition.

"We report a case of severe biventricular heart failure potentially related to excessive energy drink consumption in a 21-year-old man,'' the authors from Guy's and St Thomas' NHS Foundation Trust, wrote.

They said that the man had no medical history other than excessive intake of energy drinks - highlighted that each can the man was drinking contains 160mg of caffeine.

The doctors treating him considered a number of diagnoses, but concluded: "Energy drink-induced cardiotoxicity was felt to be the most likely cause.''

The authors said that in the three months prior to his hospital admission he was unable to continue his university studies due to his lethargy and feelings of ill health.

He spent 58 days in hospital, including a stint on the intensive care unit, which he described as "traumatising''.

"This case report adds to the growing concern in the literature about the potential cardiotoxic effects of energy drinks,'' they wrote.

After nine months his heart function has appeared to have returned with "mildly impaired function'', the added.

Doctor Katherine Markwell is a senior lecturer in Human Nutrition and Dietetics expert at the University of Central Lancashire , she said: "My first thought is we shouldn't actually call them energy drinks. That's what they're marketed as, it's not actually what they are. What they are is formulated, caffeinated beverages.

"They're processed drinks that are very high in caffeine compared to if you had a cup of tea and they used to be available in much smaller sizes when they first came out, and of course they're much larger now. They're a very new product and we don't actually know all the impacts of them yet."

The patient, who has not been named, added his own thoughts to the article, and called for more warning labels on the drinks.

"When I was drinking up to four energy drinks per day, I suffered from tremors and heart palpitations, which interfered with my ability to concentrate on daily tasks and my studies at university.

"I also suffered from severe migraine headaches which would often occur during the periods when I did not drink energy drink; this also restricted my ability to perform day-to-day tasks and even leisurely activities such as going to the park or taking a walk.

"I was eventually admitted to the intensive care unit. This experience was extremely traumatising.

"I think there should be more awareness about energy drinks and the effect of their contents.

"I believe they are very addictive and far too accessible to young children. I think warning labels, similar to smoking, should be made to illustrate the potential dangers of the ingredients in energy drink.''

It comes after a separate study, published in the journal Plos One, highlighted energy drink intake among teenagers.

Academics at Cardiff University analysed the responses of a health survey of more than 176,000 secondary school children in Wales aged 11 to 16.

The data, drawn from responses between 2013 and 2017, show that 6% of pupils said they drank energy drinks on a "daily'' basis - a trend which didn't change over time.

Study lead author Dr Kelly Morgan said: "The daily use of energy drinks among a proportion of young people has not declined - and our study reveals a widening disparity in consumption rates between those from low and high socioeconomic groups.

"Marketing campaigns for energy drinks are often aimed at those from more disadvantaged backgrounds. They are also an affordable choice and regularly available at cheaper prices than bottles of water.

"Their popularity is unlikely to wane unless legislative and policy measures are put in place.''