Coffee powder
Coffee powder Reuters

A recently released study from researchers at the University of Miami – titled Health Effects of Energy Drinks on Children, Adolescents, and Young Adults – references and lists many side effects of caffeine overdose/overconsumption.

In particular, the study focused on the adverse effects on the young. Caffeine “may be the only psychoactive drug legally available over-the-counter to children,” stated the study.

While people mostly consume caffeine from coffee and soft drinks, they are increasingly getting it from energy drinks, which are potentially more dangerous. These drinks are classified as nutritional supplements in the US so they are shielded “from the caffeine limits imposed on sodas and the safety testing and labeling required of pharmaceuticals.”

Below is a list, from the University of Miami report, of studies and cases on caffeine overdose/overconsumption:

- Short-term high-dosage intake can cause headaches, fatigue, nervousness, irritability, anxiety, insomnia, tremor, tachycardia, palpitations, and upset stomach.

-Other studies list hallucinations, stroke, paralysis, and altered consciousness as possible symptoms.

-Among children, the risks of high intake include irregular heart rhythms, syncope, dysrhythmias, and sudden death.

-Caffeine intake over 300 mg per day has been associated with miscarriages and low birth weight.

-Germany has tracked health incidents related to energy drinks since 2002. Recorded incidents include liver damage, kidney failure, respiratory disorders, seizures, psychotic conditions, heart failure, and even death.

-Between 1999 and 2005, Ireland reported 17 “energy-drink adverse events” like confusion, tachycardia, and seizures. There were also two deaths.

-Between 2005 and 2009, New Zealand reported 20 energy-drink/shot-related adverse events like vomiting, nausea, abdominal pain, jitteriness, racing heart, and agitation. There was also one case of a heart attack.


The report did point out the obvious, which is that low consumption has little or no deleterious health effects. Moreover, low to moderate consumption of caffeine improves exercise endurance, cognition, and reaction time, some studies find.

However, caffeine overconsumption is a problem that occurs frequently enough to be a serious issue. Young people are also increasingly at risk partly because of the popularity of energy drinks.

Indeed, one US study found that 28 percent of 12 to 14 year olds regularly consume them.

According to the findings of their report, University of Miami researchers recommend promoting awareness about caffeine overdose and possibly more regulation on energy drinks.