Over five years through March 2016, more than 100 people were hospitalized for emergency treatment due to caffeine intoxication and three of them died, a study by the Japanese Society for Clinical Toxicology showed Tuesday.
A leading researcher at the society warns that consumers and authorities should be more aware of the risks of ingesting too much caffeine, not only through the consumption of energy drinks but also from tablets to prevent sleepiness. The researcher is calling for tougher marketing regulations.
The society, based in Tokyo, collected the data on caffeine intoxication in a first-of-its-kind study covering 38 emergency medical institutions nationwide from fiscal 2011 to 2015.
If more than 1 gram of caffeine is ingested at any one time, typical effects are said to include intense nausea, dizziness and an increased heart rate.
Of the 101 people who were admitted to hospitals, 97 had taken caffeine tablets and some drank coffee and energy drinks at the same time, according to the figures. The 101 people included teens through those in their 50s, and the median age was 25.
“Many people are talking about the risk of energy drinks as a cause of caffeine intoxication. But the survey showed we should pay more attention to tablets that young people can easily buy,” said Yoshito Kamijo, the Saitama Medical University Hospital professor who led the research. “Authorities should set limits on the amount of tablets a person can buy at one time.”
Seven people in the survey suffered cardiac arrest, including the three who died. All seven consumed 6 grams or more of caffeine from tablets, the survey showed, noting that one of the seven ingested 53 grams.
Some had taken an excessive amount of caffeine in a bid to kill themselves, while in many other cases the substance had been consumed by people who work at night, including nurses.
Four people suffered caffeine intoxication after consuming only energy drinks, according to the report.
Japan has no law limiting the intake of caffeine.
The society launched the research in the wake of a 2015 incident in which a man in his 20s living in the Kyushu region died after continuously consuming energy drinks and drugs aimed at staying awake.