Medical professionals have issued a stark warning about the potential dangers of high-caffeine energy drinks, following the case of a man in his fifties who suffered a stroke after consuming eight cans daily.
A Life-Altering Habit
The patient's case, detailed in the BMJ Case Reports by Nottingham-based doctors, revealed a direct link between his beverage choice and a serious health crisis. The man was admitted to an NHS hospital after having a stroke. Despite being prescribed a cocktail of medication, his blood pressure remained stubbornly high after he was discharged.
It was only when clinicians probed deeper into his lifestyle that they uncovered his extreme consumption habit. He was drinking eight strong energy drinks every day. Suspecting a connection, doctors advised him to stop immediately.
The results were dramatic. After quitting the drinks cold turkey, his blood pressure returned to normal levels, allowing him to cease all medication and return to full-time work.
The Hidden Caffeine Danger
The specific drinks the man favoured contained 160mg of caffeine per 455ml serving. Consuming eight of these meant his daily intake was a staggering 1,200 to 1,300mg of caffeine. This dwarfs the recommended maximum daily allowance of 400mg for adults.
Researchers cautioned that the listed 'pure caffeine' content is only part of the story. Other common ingredients like guarana contain additional caffeine – thought to be at twice the concentration of coffee beans. Furthermore, compounds such as taurine, ginseng, and glucuronolactone may amplify caffeine's effects, potentially heightening stroke risk.
The man himself stated: ‘I obviously wasn’t aware of the dangers drinking energy drinks were causing to myself. I have been left with numbness (in my) left hand side, hand and fingers, foot and toes even after eight years.’
Calls for Tighter Regulation
This case ‘closely mirrored’ a previous incident involving a 16-year-old boy, whose hypertension also normalised within two weeks of giving up energy drinks. The authors of the report noted that while risks for obesity and diabetes are known, ‘less explored are the possible increased risks for cardiovascular disease’, including strokes in younger people.
While evidence is still being gathered, the doctors propose that ‘increased regulation of energy drink sales and advertising campaigns (which are often targeted at younger ages) could be beneficial’ for public health.
Currently, major UK supermarkets voluntarily ban sales to under-16s, a rule instituted in 2018. However, children can still purchase them in some convenience stores and newsagents. In September 2025, the government confirmed its intention to implement a complete ban on sales to children under 16, following a consultation.
Shadow Health Secretary Wes Streeting has likened the drinks to ‘necking four cans of coke’ and warned they are fuelling anxiety and depression in young people.
